CP-CBU-125

Capstone Project Department of Mechanical Engineering

Final Report 2012 Project Title:

Optimizing Rainwater Harvesting in Rural Cambodia

Date:

15/10/2012

Identifier:

CP–CBU-125

Student workers:

Jack Clarke, 356399 Zachary Parsons, 359487 Grace Lee, 256089 David Barnes, 359129

Academic supervisor: Colin Burvill Academic examiner:

Andrew Wirth

Client Organisation:

Mr Pheng Kea RainWater Cambodia http://www.rainwatercambodia.org/ #11A Street. Lum (02),CPC Village Sangkat Teuk Thla, Khan San Sok, Phnom Penh, Kingdom of Cambodia +855 (0)23 630 4030

External Mentor:

James Oakley Engineers Without Borders, (WASH Technical Advisor) +855 978489287 [email protected] Version: #Final Draft, 11/10/2012 Final Report 2012

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Acknowledgments The Project Team would like to thank the following people for giving up their time and effort to contribute to the project: Rainwater Cambodia James Oakley, Engineers Without Borders Field Engineer at Rainwater Cambodia Dr Colin Burvill, University of Melbourne Engineers Without Borders, Australia Julian O’Shea and Terri Maher, Engineers Without Borders Associate Professor Jim Black, Nossal Institute of Global Health Naomi Francis, Nossal Institute of Global Health Niruma Akhter, ARUP Lachlan Challis, BA The University of Melbourne’s Engagement and Partnership Office Dr Terry Thomas and Brett Martinson, from the Development Technology Unit at the University of Warwick. This report draws extensively on their work, especially the summaries provided of research to date. The authors would like to thank and commend them for the excellent work they are doing in the field of rainwater harvesting for low income countries.

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CP-CBU-125

Contents 1.

Executive Summary

4

2.

Introduction

9

3.

Literature Review

10

4.

Project Scoping

26

5.

First Flush Solutions

29

6.

Tank Solutions

46

7.

Education

55

8.

Conclusions and Recommendations

69

9.

References

77

Appendices A.

Rainwater Cambodia’s Existing System

80

B.

First Flush

101

C.

Tanks

174

D.

Education

209

E.

Construction Manuals

260

F.

Gantt Chart

301

G.

Meeting Minutes

306

H.

Timesheets

367

I.

Design Diary

385

J.

Field Work in Cambodia

386

K.

Risk Analyses

397

L.

Scope of Works

401

M.

List of Digital Resources on CD

408

N.

Grants and Awards

411

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CP-CBU-125 1. Executive Summary The majority of rural Cambodian residents live using a variety of sub-standard water sources. This exposes them to a variety of health issues, including a variety of waterborne diseases. Villagers must also travel great distances and expend large amounts of time and effort to obtain the sub-standard water. One solution practised by locals is Rainwater Harvesting (RWH). RWH is the capture of rain water, usually from a roof into some form of storage. RWH has existed in Cambodia for some time as a means of reducing the travel time and effort involved in water. RWH has the ability to produce high quality water when efficient practices are in place. Due to limited access of quality water in rural Cambodia there is a need for sustainable water solutions. Cambodia’s high annual rainfall makes RWH the most appropriate technology, despite the complications of a monsoonal climate.

Figure 1.1: A typical school RWH system built by RWC [1]. Rainwater Cambodia (RWC) is a Non-Government organisation (NGO) operating in Cambodia and managed by Cambodians. RWC focuses on RWH in rural Cambodia with the overarching principal of reducing risk to the recipients of the implemented systems. RWC has assisted over 100,000 people to gain access to safe drinking water through formalised RWH. RWC are currently assisted by Engineers Without Borders (EWB) Australia, an NGO that works in partnership with Australian and overseas communities to develop knowledge, resources and appropriate technologies to improve their quality of life. This is facilitated by EWB Field Engineers in Cambodia working directly with RWC staff in order to fully understand the context of the community, the issues and the solutions.

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Figure 1.2: A typical domestic RWH system built by RWC [2]. RWC has a well-established RWH model that they assist communities to purchase, understand and install. This RWH system has a number of areas that could be improved and EWB and RWC have engaged the University of Melbourne (UoM) and Capstone Project Team CP-125 (henceforth referred to as Project Team) to help improve these areas. The project aims to optimise RWC’s existing RWH system. The current RWH system issues outlined by RWC are included in Table 1.1. Table 1.1: RWH system issues identified by RWC. Issues Identified by Rainwater Cambodia The lack of maintenance of the RWH systems The high upfront cost of the systems installation The lack of knowledge and understanding of drinking water quality, hygienic practices and the health risks involved The failure or poor performance of particular RWH system components (such as the leaf filters, tank seals and first flush system) Working in partnership with EWB and RWC, the Project Team’s work on this project can be split into 3 phases; project scoping, literature review and lastly, designing and prototyping. The project scoping phase involved discussions with RWC and EWB to work through what key optimisation areas were relevant, achievable, valuable and deliverable. This was a key learning outcome for both the Project Team and RWC. This phase also outlined the importance of a multi-faceted, community focussed approach to solution design that has been crucial as the project has developed.

Tank Optimisation

First Flush

Education

Figure 1.3: The 3 key focus areas of the project. Final Report 2012

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CP-CBU-125 The literature review phase considered all pre-existing deigns in similar countries around the world, as well as community populated awareness and education program research. As the literature review progressed 3 key focus areas emerged; Tank Optimisation, First Flush Optimisation and Education. Specific research, including discussions with industry professionals in these areas, provided valuable solutions for RWC and the Project Team. The final stage consisted of designing and prototyping both new designs and existing designs from different locations around the world. The most promising prototypes were taken to Cambodia to be tested with RWC, whilst others were built on site in rural Australia by the Project Team. Table 1.2: The delivered outcomes from the project. Project Deliverables Alternative tank design review, construction and recommendations Recommended solutions to the issue of locals cutting open the pipe to the primary tank for secondary quality water addition Recommended solutions for leaking release value and leaf filter issues Education, community and cultural awareness field survey outcomes presented and recommendations given. First Flush design review, construction of modifications and recommendations Educational model and revised information pamphlet for implementation by RWC An extremely thorough literature review and analysis of RWC’s current system and practices for further research groups to build on.

Figure 1.4: The Tarpaulin Tank, a low cost tank alternative constructed by the team in rural Victoria, Australia.

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CP-CBU-125 This project is specifically tailored to RWC’s RWH system but the proposed solutions have the potential to be implemented in many similar situations around the world. The project was recognised by the UoM and EWB, receiving a Vice Chancellor’s Dreamlarge Community Engagement Grant. The grant allowed the Project Team to travel to Cambodia to work with RWC and EWB to implement some of the prototypes and educational models in the context for which they were designed. The field work focussed on 5 main goals: 1. Contextual investigation of alternative tank design. 2. Costing of a series of alternative designs. 3. Community research pioneering new education models for RWC, to enhance awareness and knowledge of RWH. 4. Testing improved FF devices and innovations. 5. Costing and testing solutions to leaking tank issues. The field work provided an opportunity for the team to implement new design ideas within the community they were designed for and in doing so to further enhance the value of the delivered solutions to RWC. Working with the staff at RWC the team was able to build and conduct testing on 7 first flush prototypes, the most promising of which were left assembled on a test rig built at the RWC office. The prototypes will be tested over the next 12 months by RWC in order to assess any durability and maintenance issues. The project team visited local communities where the RWH systems have been installed to collect information on the attitudes, knowledge and understanding of the systems by the local residents. This information is critical to designing the most appropriate technology for RWC.

Figure 1.5: The Project Team in Cambodia. Visiting a local entrepreneur (left) and a community health centre (right).

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CP-CBU-125 Both EWB and RWC are committed to a lasting partnership to create real value for the rural communities in Cambodia. The Project Team hope that this project will continue at the UoM in 2013 and further final year students gain the opportunity to deliver sustainable change to the communities that need it most.

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2. Introduction This report investigates an existing rainwater harvesting (RWH) system installed in rural Cambodia and presents a number of potential improvements to optimise the system. Each technical component of the current system is analysed and documented. Recommendations to improve the current system based on research and, in some cases, field studies are made. The report then examines the community, contextual and educational aspects of the current RWH system and outlines why these are crucial factors in technological development. Further recommendations are made for the education and awareness aspects of rainwater harvesting in the Cambodian context. This research project forms part of Engineers Without Borders’ (EWB) project to provide resources and technical support for a local Non-Government Organisation (NGO) based in Phnom Penh, RainWater Cambodia (RWC). [3] provides an excellent summary of RWC and the work they are involved in. Like other NGO’s, RWC receives funding from various aid organisations to conduct their work including GRET, UNICEF, European Union, ASIA Foundation, World Bank and the Gates Foundation. Households are selected to receive a subsidised RWH system, based on a government classification that places them in the poorest bracket of the rural population. These households contribute 5-30% of the total cost of the system, with the rest of the cost of the project covered by aid funding. The EWB support of RWC is provided by a trained field engineer, who will work with RWC for a 12-24 month period to provide technical expertise, training, and to work with RWC staff. This project is the first year an undergraduate research team has provided assistance to the field engineer in Cambodia. As such, one of the project outcomes will be to deliver a fully documented platform which follow on research teams will be able to build on, to create further value for RWC in the future. This project focuses on one RWH system in the specific context of rural Cambodia, but many of the proposed design solutions and field prototypes tested would be of equal benefit to other developing communities around the world. Whilst statistical data, component design and theoretical literature are quite available in the area of low cost RWH, unfortunately practical manuals for their implementation are not. This report will contribute to this area of research and be of practical use in the implementation of low cost rainwater harvesting technology.

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3. Literature Review 3.1 Rainwater Harvesting in Cambodia There are around 780 million people without access to an improved drinking water source [4]. An improved drinking-water source is defined as one that, by nature of its construction or through active intervention, is protected from outside contamination, in particular from contamination with faecal matter [5]. The direct result of this water access disadvantage is, amongst other issues, the death of 1.8 million children every year [6]. The Cambodian context is quite similar, where only 58% of rural Cambodian’s have access to clean drinking water [7]. This is due to a combination of arsenic affected groundwater [8-12], poor water infrastructure [13, 14], poor water quality [13, 14] and poor economic conditions [13] of many rural inhabitants. The World Health Organisation (WHO) estimates the number of deaths in Cambodia due to the lack of adequate water for drinking, sanitation and hygiene to be 10,600 per year [15].

Figure 3.1.1: A map showing the widespread poor water quality in 5 central provinces of Cambodia. Note the darker the shaded region, the lower the water quality [16]. Local government, NGO’s and development organisations such as the United Nations Development Programme (UNDP) are working hard to improve the Water, Sanitation and Hygiene (WASH) sector in Cambodia [6, 17]. Mass education programs exist to educate school children about hygiene [18] and country wide mapping of safe ground water sources are ongoing. Ceramic water filters are now widely available to reduce the risk of drinking unsafe groundwater [19] and RWH is becoming more widespread in practice and understanding [6, 13, 14, 18, 20]. Research shows that 97% of rural Cambodians use some form of rainwater harvesting, often small, open top concrete ‘Pbeng’ jars of 200-400L capacity [13]. Inhabitants are generally Final Report 2012

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CP-CBU-125 satisfied with this water source as it is cheap, easy to maintain and suppliers exist. However there are complaints that they don’t store enough water, attract mosquitos and take up space around the house [13]. Notice none of the responses are based on the quality of the drinking water, although research [13] shows that communities are aware of the health benefits.

3.2 Water Quality There are many issues to consider when dealing with water quality, such as sodium levels, microbial activity, presence of metals and pH. An established overall measurement and the industry standard is Turbidity, or the amount of particulate matter present in a water sample [21]. Turbidity is measured in units of Nephelometric Turbidity Units (NTU). A turbidity of less than 5 NTU means no particles are visible to the naked eye and can be determined more specifically with a turbidity tube test [21]. Figure 3.2.1 shows what the turbidity levels look like to the naked eye.

Figure 3.2.1: Three water samples with turbidity level added [22]. The World Health Organisation (WHO) current guidelines are that drinking water should have a turbidity of less than 5 NTU [23]. A field textbook published by [24] draws the same conclusions. RWC has adopted these guidelines in accordance with the drinking water standards in Cambodia [25]. The guidelines are shown in Table 3.2.1 and have been used as design criteria for any recommended system in this report. Rainwater is a high quality water source to begin with; therefore the quality of any RWH system is determined by the amount of contaminants that are able to enter the system during capture, transfer and storage. [26] provides Figure 3.2.3 to trace the contaminant path through the system.

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Figure 3.2.3: The path of contamination in a RWH system [26].

Table 3.2.1: The key parameters in the Cambodian Drinking Water Guidelines [25]. Parameter pH Turbidity Arsenic Iron Total Dissolved Solids (TDS) Thermotolerant Coliforms (including E Coli)

Maximum Value 6.5-8.5 5 NTU 0.05 mg/L 0.3 mg/L 800 mg/L 0 per 100ml

RWC is focussed on RWH in rural communities, but in a way that reduces the risk [1]. RWC and other RWH practitioners must keep in mind the contaminant path shown in Figure 3.2.3 when designing systems for water quality. RWC have an existing high quality RWH system which has proven successful in communities throughout Cambodia. When properly maintained it meets all of the design criteria listed in Table 3.2.1. RWC’s current system includes a number of components, on which there are varying amounts of supporting literature.

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CP-CBU-125 3.3 RWH system components Roofing The roof is the catchment area of many RWH systems. The catchment area determines the maximum volume of water that can be stored in a RWH system. The calculations in Appendix C6.1 show how the size of the tank is calculated. The required area of the roof can be calculated using the volume of water needed to be captured per year. A runoff coefficient is used in this calculation, which represents water lost from splash and evaporation. Alternatively, if the area of the roof is the limiting factor, the maximum volume of water captured each year can be calculated. The equations to calculate the area of the roof and the maximum annual volume captured from a certain sized roof are found in Appendix C6.2. A low runoff coefficient represents more wasted water due to evaporation and splash. If the runoff coefficient it is too low, it can waste a large volume of water. As seen in Table 3.3.1, galvanised iron sheeting has the best run-off coefficient of commonly used roofing materials. In most developing countries, this is an economically viable option. A major requirement is that water running off the roof must not contain any poisonous contamination. The notes in Table 3.3.1 comment on water quality from different surfaces. Asbestos sheeting is often avoided for this reason, even though there is no evidence to suggest that it can make the water carcinogenic. Table 3.3.1: Roof runoff co-efficient of different materials [26]

Guttering and Piping Guttering and piping takes the water from the roof to the storage device. It is important that as little water as possible is lost due to insufficient sizing or poor connections. Gutters should be sized to a depth at which there is no spillage, even in the heaviest rainfall event. Piping is quite often made from Unplasticised PolyVinyl Chloride (UPVC - commonly just PVC) due Final Report 2012

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CP-CBU-125 to its low cost and worldwide availability. Lower cost systems may utilise bamboo or other cylindrical organic material as a cheaper substitute with an associated loss in quality. The layout of the guttering and piping depends on the following:   

Whether both sides of the roof are used for catching water Size of the catchment area Number of tanks installed

Based on these variables, the layout of the guttering and piping can be summarised in Table 3.3.2. Table 3.3.2: Summary of different guttering and piping layouts [26]

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CP-CBU-125 The guttering and piping can be used as the first defence to contaminated water. Filtering and screening blocks particles, both large and small, as the water flows from the roof to the storage system. There are a range of opportunities to filter water from the roof to the storage device, which are summarised in Table 3.3.3. Coarse filters block the passage of large matter, usually with a 5mm grid. It is necessary to block large matter so it does not settle at the bottom of the storage system and decay. Coarse filters can also be used to stop animals entering the system. Maintenance is easily achieved if the filter is located in an accessible location. Fine filters are used to ensure the water that is harvested is suitable to ingest. Fine filters in developing countries are often made up of sand or rocks located at the entrance of the tank. The problem with fine filters is that they often become blocked and are rarely maintained. A substitute for a fine filter is a first flush system, explained in detail in the first flush literature review. Table 3.3.3: The Advantages and Disadvantages of filter location [26]

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CP-CBU-125 First Flush System The aim of a first flush system is to remove from the system some initial amount of water during a rainfall event. This ‘first flush’ water is often contaminated with organic matter that has collected on the roof, guttering and piping system and has then been carried toward the tank during the first rain event. Studies have shown [26-32] that first flush systems substantially reduce the contaminant load in RWH systems. One study [33] claims that 90% of contaminant material can be removed with only a 15% loss in water catchment. By removing this contaminant load, the water in the tank remains high quality and meets the criteria in Table 3.2.1. Table 3.3.4 highlights the design criteria for an appropriate first flush system. Table 3.3.4: Criteria for an appropriate first flush system [26]. First Flush Criteria Be capable of dealing with high rainfall intensities Easy to clean or largely self-cleaning Will not block easily (if at all) and blockages should be easy to see Will not become a source of additional contamination if left uncleaned The cost of the inlet filter should not be too high (10% of the tank cost should be considered a maximum) The amount of water lost by diversion or for washing the filter should be only a small part of the total flow. There are two main parameters in a first flush system. The first is the amount of water to be flushed during an initial rainfall event. There is a large amount of debate around how much water should be flushed, as various authors have presented models based on different design objectives, environments, roof sizes and methods. The current literature is summarised in Table 3.3.5. The research presented by [27, 32] seems the most promising. [27] reviews all current research and then proposes a contaminant load dependent model for quantifying the volume of first flush water to be removed from the system. An implementation table for this method is included in Appendix B1.2.

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CP-CBU-125 Table 3.3.5: The recommended amount of water to be flushed by the first flush system in current literature. This is an extension of a summary in [26]. Amount of Water Flushed 20 Litres per 100m2 roof area 0.33mm 0.83mm or first 10 mins 20-25 Litres 0.2 - 2mm depending on pollution level First 10 minutes of rainfall 0.5mm 0.41-0.82mm 0.28mm 1mm after 3 dry days Every mm flushed, the contaminant load will halve

Source Australian Standards [34] Yaziz, et al. [35] Ntale, et al. [30] Cunliffe [28] Rain Harvesting [36] Pacey and Cullis [37] CEHI [38] TWDB [39] Michaelides [40] Doyle [29] Martinson [27], Kus et al [32]

The second parameter of interest in first flush systems is the reset time. Much less research exists in this area but [33] has modelled reset time and its effect on contaminant removal extensively. [33] produced an equation for the calculation of reset time based on curve fitting of experimental models. [41] found that the cost saving option of small volume first flush systems with a short reset time produced poor contaminant removal efficiencies. The equation in [33] is included in Appendix B1.3 but the author cautions at its use, claiming the long reset time adds further complication to the RWH system. However, [42] reports successful first flush diverters with long reset times. For many designs the reset time is a function of the pressure head on the first flush system. Once the reset time and amount to be flushed are decided, an appropriate design can be chosen. Table 3.3.6 summarises the various distinct types of first flush system and a full analysis of each design can be found in Appendix B2.

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CP-CBU-125 Table 3.3.6: First flush system designs. Design

Comments

Fixed Volume

Fixed volume pipe with bore hole or manual release

SSWM [43]

Fixed Volume, Ball-valve

RWC’s current design. Fixed volume, with one-way ball valve

Australian Government [44]

Manual Flush

Downpipe is manually directed away from tank to flush water

Fixed Mass

Tipping gutter, tilted by mass of ‘flushed’ water

REUK [46]

Flow Rate Ball Valve

Hollow ball closes valve when filled with water

Saferain [31]

Vortex Filter

Removes debris by creating a vortex through a filter. Not strictly speaking a first flush system

WISY [47]

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Image

Source

PacificWater.org [45]

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CP-CBU-125 Pumps, Taps and Seals Taps and seals in low cost RWH systems are often poor quality and can be the source of contamination of the system. [26] outlines the contaminant path in RWH systems, as shown in Figure 3.2.3. Direct entry into the tank via hands, containers or hoses poses a potential contaminant threat to the system. To avoid this route of direct contamination, taps are often constructed in above ground RWH systems. Pumps are constructed in below ground systems for the same reason. The most common, simple and appropriate pump for most low income situations is the rope pump. [4853] show more information on various rope pump designs, construction information and maintenance procedures.

Figure 3.3.1: A low cost Rope Pump constructed and widely distributed in Cambodia, built by Resource Development International Cambodia in Phnom Penh. To obtain contaminant free water, above ground systems often use a pipe or tap to dispense water. These systems are most commonly driven by gravity, with the tap or pipe at the base of the tank. This may be done in a simple manner, such as the siphon hose used in Figure 3.3.2 or by a more complex, higher quality fitting such as a plastic tap. The industry standard for taps and the seals associated with their installation in Australia is covered by [54]. These standards recommend the use of hydrophilic sealants such as Hydrotite [55] for typical plastic-concrete connections between the tap and tank wall. No such standards code exists in Cambodia for RWH systems, although the Cambodian Society of Civil Engineers (CSCE) is an industry group based in Phnom Penh that may be able to provide standards information. [26] provides rule of thumb guidelines on the installation of low cost RWH systems and is further discussed in later sections of this report.

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CP-CBU-125

Figure 3.3.2: A basic siphon hose system used to decant water from the tank.

Tank Systems Tanks are often sized using either a demand approach or a supply approach [56]. The demand approach aims to calculate the largest required storage based on estimated consumption rates [56]. The demand approach assumes that there is enough annual rainfall, a large enough catchment area and that all rain caught is stored [56]. This is usually an unreasonable set of assumptions as all three are often unattainable in areas like rural Cambodia. The supply approach is used when there are periods of the year where the supply exceeds demand, while other periods result in a deficit of caught water [56]. The equations for calculating tank size using both approaches are included in Appendix C6.1. Once the tank size is justified, a range of other parameters must be considered before choosing an appropriate tank. The minimum design requirements and the optimised parameters are summarised in Appendix C2. A list of existing designs is listed in Appendix C3, while a short summary of these tanks can be found in Appendix C1. The storage tank is the largest contributing factor to the start-up costs of a RWH system [57]. Large storage tanks are often desirable as they can minimise the impact of seasonal fluctuations in rainfall [27]. Large tanks are also more suitable for areas which experience long dry seasons [27]. Minimising tank installation costs per litre of storage is therefore the easiest way to reduce the overall cost for a RWH system whilst having a suitably large storage tank. Increasing the size of a tank decreases the cost per litre of storage [27]. However, increasing the size of a tank does not necessarily decrease the cost per litre delivered [27]. Accurately predicting the necessary size of the tank is imperative to implementing the lowest cost per litre delivered RWH system.

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CP-CBU-125 It is often necessary to optimise the design of an existing tank to take advantage of the specific environment. Once the type of tank is selected, there are a number of secondary components to consider [58]. These include:      

Inlet: How the water enters the tank. Outlet: How the water is extracted from the tank. Overflow: How the water exits the tank when it is overflowing. Drainage: How the tank can be quickly emptied for cleaning. Fittings: The suitable fittings for the above processes. Seals: To stop leaking where cement meets fittings.

The method chosen for the inlet, outlet and overflow of a tank can have an impact on the overall quality of the water consumed [58]. As the time water has been occupying a tank increases, the quality of the water increases [58]. Therefore, water entering the tank will be of lower quality than the water already in the tank. If water is left in a tank to settle, the water at the surface will be of higher quality than the water at the bottom of the tank [58]. It is desirable for the inlet water to not disturb the high quality, settled water at on the surface [58]. This can be achieved by installing a down pipe to the bottom of the tank with the outlet encased by a ridged semicircle, known as a break ring, seen in Figure 3.3.1.

Figure 3.3.3: The break ring inlet arrangement [58]. The water just below the surface is the highest quality available in the system, as the topmost surface water may include floating contaminants. It is therefore advantageous to extract the near surface water by using a specific outlet arrangement [58]. This arrangement uses a flexible hose with a floatation device attached to the inlet of the hose. The outlet of the hose connects to the outlet of the tank, depicted in Figure 3.3.4.

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Figure 3.3.4: The flexible hose outlet arrangement, used to harvest the high quality nearsurface water [58].

The quality of water which is being expelled when the tank reaches maximum capacity should also be scrutinised. Different environments and tanks require varied solutions for expelling the lowest quality water. Table 3.3.7 summarises the alternative overflow arrangements.

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CP-CBU-125 Table 3.3.7: Summary of overflow arrangements Method

Image

Standard Arrangement [58]

Inflow Exclusion [58]

Description

Positives

Negatives

The simplest arrangement. When water rises above the outlet, the surface water drains until below the outlet

This method is simple, cheap and easy to maintain.

This method expels the highest quality water in the tank

This method does not allow lower quality water to enter the tank

More pipes are necessary, so it is more expensive. The entering water is most likely cleaner than the water at the bottom of the tank.

The lowest quality water is removed from the tank. This means less cleaning is necessary as the sludge build up is also removed

Expensive with pipes. The pipe either needs to be well secured coming out of the bottom of the tank or secured tight on the inside of the tank. Leaking may be an issue.

Cleans the top of the tank from leaves and debris

Only useful for tanks with substandard screening before the tank or open tanks

The overflow does not allow the inclusion of incoming water

Desludging Overflow [58]

The outlet pipe runs from the bottom of the tank to the desired height of overflow. As the water rises above the desired height, water is sucked from the bottom of the tank

Top Cleaning [58]

The opening faces upwards, so when the water level rises above the inlet, suction is created.

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CP-CBU-125 3.4 Education The development of an appropriate RWH system is useless if the local residents don’t have the knowledge to operate and maintain the system. Thus, every RWH program around the world includes a substantial education program to engage the local community. Education is an important factor in the RWH system’s sustainability, as it is a major reason many RWH programs fail. Education not only involves educating individuals about new processes, but also includes educating the organisation, group or individual who is implementing the program. It is important that those who aim to implement an educational model have an understanding of what the community wants, as well as what works and does not work. This understanding is commonly termed as Community Engagement [59]. Community engagement involves communicating with the community group. It also involves empowering the community’s interests and taking the needs of the stakeholders into account [59]. As such, it is imperative that a sound understanding of community engagement is achieved. In developing countries, many water and sanitation programmes have not been successful for a number of reasons including: 1. The financial cost may be unaffordable. 2. Communities or households have never been convinced of the desirability of the new system. 3. Communities or households may never have felt ownership of the new facility. 4. Attitudes and behavioural changes expected to be achieved (from community education) take a long time [59].

Research has also identified that there are a number of factors that contribute to the success of education programs in developing countries [57]. These factors include: 1. Education levels of participants 2. Pressure of time and space 3. Staff members’ communication skills

Research has also identified Interpersonal Communication (in the form of home visits and group training) as an important tool for passing on educational knowledge and information [58]. It is important that any intervention is culturally sensitive and accessible, and should be integrated with local resources [60]. When designing and implementing a WASH model, it is important to realise and acknowledge that in developing countries and traditional societies, women are the primary users of domestic water supply. Women in all communities have specific but different duties, rights and expected norms of behaviour. They often have a great deal of power and influence

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CP-CBU-125 in decision making, when the topic of discussion revolves around the domestic domain [60]. Women’s roles can be categorised into 4 categories: 1. 2. 3. 4.

Women as acceptors of the new model/technology. Women as users of the improved facilities. Women as managers of sanitation programs and water supply. Women as agents of attitude and behavioural change in the use of the improved facilities.

Women workers generally understand (more intuitively) the issues encountered and faced by other women, consequently they tend to be able to communicate more openly with other women. As such in the promotion of new or improved WASH programs women should be recruited wherever possible [60]. Nonetheless, the degree to which women can assume these particular roles (within the community), depends on the degree to which the local culture and community are accepting of these more public roles for women. In conclusion, when designing a new model, it is important to consider the factors that contribute to the success of WASH programs. It is also beneficial where possible to recruit women in the promotion of WASH programs. Taking these considerations into account will be a great start to ensuring the best possible outcome when designing and implementing a new or improved RWH project.

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CP-CBU-125

4. Project Scoping Project scoping was an integral aspect of this project. The Project Team were required to identify the issues faced by RWC and define the full scope of the project. This was a very involved and challenging task. Developing the project scope required constant communication with partners who were located overseas, which proved to be difficult. The Project Team views the developed scope as a major outcome and success. The original project scope was to “design a maintenance-free rainwater harvesting system”. The Project Team investigated areas of the RWH system that required maintenance. Areas that require maintenance included the tank, gutters, pipes and first flush system. It became evident that the consequence of failing to maintain the first flush was the largest contributing factor to contaminated water. Consequently, the project was tailored to designing a maintenance-free first flush system. Consultations with RWC and EWB Field Engineer James Oakley led to the analysis of the entire RWH system. The aim was to systematically reassess the system RWC have been building for more than 15 years and to document the associated issues. As more issues slowly emerged the scope continuously evolved. As more research was conducted, it became apparent that many of the problems stemmed from the recipients’ lack of understanding regarding the importance of cleaning the system. As such, the Project Team included a review of the education model in the scope.

4.1 Education Scope Originally the aim for this area of study was to alter the villagers’ behaviour by assisting RWC with their education program. The project then became categorised into two different areas; Technical and Education. Technical aspects of the RWH model include:      

Roofing Guttering Piping Filters First Flush System Tanks

The development of the education section was initially intended as part of the solution to the following issues:   

Lack of maintenance of the first flush system. Intentionally blocking the first flush bore hole. Cutting open pipes to introduced second class water.

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CP-CBU-125 The scope of the technical area included a review of the existing system, containing as much information as was deemed necessary for third parties to understand RWC’s system. This review is included in Appendix A. The technical aspects of the project then progressed to prototyping of designs, which are discussed in Section 5 and Section 6 of this report. Similarly to the technical areas, the scope of the education area developed continuously. During the course of the project, factors were identified that suggested attempting to improve the education program would be ineffective and not beneficial for RWC. Factors include:    

Not having detailed information about RWC’s education program (due to difficulties in obtaining information by email). Culture differences. Context differences (including level of education, budget and costs of implementing the programs). Difficulty in obtaining information regarding the attitudes and values of rural Cambodians towards WASH.

The Project Team engaged the Nossal Institute of Global Health for assistance and guidance regarding the education component. Associate Professor Jim Black and PHD student Naomi Francis offered their expertise. These discussions identified the importance of community engagement. It became clear that the Project Group needed to understand the attitudes, beliefs and values of rural Cambodians. It became apparent that conducting research in villages and interviews with RWC during the mid-September visit to Cambodia was necessary. With the assistance from the Nossal Institute of Global Health, a questionnaire was designed to obtain specific information. The questionnaire (in Appendix D4) was aimed at recipients and non-recipients of rainwater harvesting tanks, which covered five areas: 1. 2. 3. 4. 5.

Rainwater tanks Quality of water Storage Water requirements Health

After numerous meetings with the organisation and EWB, it was realised that the research would not be able to be completed during the course of the Project Team’s visit to Cambodia, as time was a restriction. In addition, there were concerns from EWB about the Project Team’s experience in conducting the formal structured research. EWB was concerned that the project team may diminish RWC’s reputation in the communities they serve. The Project Team took the feedback on board and decided to obtain the required information with structured interviews with members of RWC, and unstructured and informal discussions with the stakeholders. Final Report 2012

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The Project Team reviewed the scope and decided on two main objectives: 1. To gather information for RWC 2. To gather information for future groups and individuals 3. To use the information gathered to make amendments to the information pamphlets distributed by RWC, as part of their RWH education program. This was the finalised scope for the education section and the outcomes of the information obtained proved to be very beneficial to RWC. Further discussions on the educational and technical components of the project are included in subsequent sections of this report.

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5.

First Flush Solutions

5.1

First Flush Specifications and Design Criteria

Based on the rural context in which the RWH system will be implemented, and current literature summarised in Table 3.3.4, a list of design criteria was created for the first flush system. The criteria are shown in Table 5.1.1. The main criteria specific to RWC’s needs are that the system must be cheap, simple and close to maintenance-free.

Table 5.1.1: Criteria for an appropriate first flush system for use in rural Cambodia 1. 2. 3. 4. 5. 6. 7. 8.

First Flush Criteria Will be capable of dealing with the high flow rates experienced in Cambodia. Will require less maintenance than RWC’s current system (3 times a year). Will not block easily (if at all) and blockages should be easy to see. Will not become a source of additional contamination if left un-cleaned. The amount of water lost by diversion or for washing the filter should be only a small part of the total flow. Will be made from locally available materials. Will be cheap and easy to produce in bulk. Will function without user input.

In order to better assess potential new designs in the prototyping phase, rainfall intensity data was analysed to quantify criterion one in Table 5.1.1. In the absence of data specific to Cambodia, a study from monsoonal India was used [61]. In conjunction with estimates of the catchment area and guttering capacity of RWC’s RWH system, this data was used to establish an estimated range of operational flow rates, shown in Table 5.1.2. These flow rates were used to test first flush prototypes. Appendix B1.1 provides a full discussion of the methods used to obtain these values.

Table 5.1.2: Estimated Operational Flow-Rates Precipitation Intensity, PI (mm/hr.) 1 2 5 10 20 40 70 130

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Flow Rate, FR (L/min) 0.4 0.7 2 4 7 15 25 50

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CP-CBU-125 Given the fact that the Project Team’s main brief regarding the first flush system was to reduce the need for maintenance, it was decided that new prototypes would flush 10L, unchanged from RWC’s current system. However, a sizing analysis of RWC’s first flush, based on the literature, was conducted, and is discussed in Section 5.7. It was decided that the reset time would be made as long as possible. This is because the optimum reset time is a few days, whereas the maximum achievable reset time is generally a few hours [33]. The rationale behind this decision is discussed further in Appendix B1.3.

5.2

Evaluation of Existing Alternative First Flush Systems

Only two alternative designs are discussed here. The first is the ‘Constant Volume with Ball Valve’ design, because of its ubiquity in first-flush systems across the globe and the fact that it is the system currently in use by RWC. The second is the ‘First Flush Ball Valve’ design, as it was selected for prototyping. Several other designs were evaluated but deemed unsuitable before the prototyping phase for various reasons, and are discussed in Appendix B2.

Fixed Volume Ball Valve Rain flows from the gutter into the first flush chamber until the floating ball seals the entrance. Rainwater then flows into the storage tank. Water drains from the first flush chamber at a slow rate through a drainage-hole, so that after a period without rainfall the chamber is empty again. The debris remaining in the chamber must be cleaned out at least three times a year to prevent the drainage hole from becoming blocked.

Figure 5.2.1: Fixed Volume Ball Valve [62].

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CP-CBU-125 Table 5.2.1: The advantages and disadvantages of the fixed volume ball valve design. Advantages Only one moving part (floating ball) Fixed and easily controlled volume of water flushed (the volume of the flush chamber is the volume flushed) Simple design

Disadvantages Requires manual cleaning, which is often not carried out Becomes useless if cleaning is not carried out- contaminated water will flow directly into tank

First Flush Ball Valve As depicted in Figure 5.2.2, a hollow ball is suspended on a spring within the first flush chamber. The mass of the empty ball is insufficient to close the valve. During rainfall, the initial flow will be diverted straight through the first flush chamber. There are screened openings through the top of the ball, through which it slowly fills with rainwater, and eventually the ball is heavy enough to close the valve. The chamber is then filled, and further rain flows to the storage tank. A drip hole in the bottom of the ball allows the system to reset over a period of time. Any sediment/debris remaining in the chamber is flushed out with the next rainfall [31].

Figure 5.2.2: First Flush Ball Valve design [31].

For the valve to close, the rate at which the ball captures water through the openings must be greater than the rate at which water drains through the drip-hole. As such, First Flush Ball Valves are sometimes considered to be ‘flow-rate controlled’ (distinct from more common fixed volume or mass methods) [31, 63]. For this method to be successful, the flow rate must be sufficient to close the valve within a reasonable amount of time. The amount of water to be diverted can be adjusted in one of two ways: Altering the flow rate into the ball by changing the size of the holes, or adjusting the height from which the ball hangs.

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CP-CBU-125 Table 5.2.2: First Flush Ball Valve, Advantages and Disadvantages. Advantages Suited to monsoonal climates (sufficient flow rate). First flush chamber is selfcleaning.

5.3

Disadvantages Less direct and more complicated way of controlling volume to be diverted than fixed volume/mass designs. Relatively complicated design relative to alternatives, more moving parts than RWC’s current design. If drip-hole in ball becomes blocked, system will not reset and no water will be diverted. Difficult to clean inside ball if required.

Development of New First Flush Systems

First Flush Design Process Of the criteria listed in Table 5.1.1, the current RWC design meets all except for the first. Hence, the design objective was to remove or reduces the need for maintenance, without sacrificing any other criteria. Two design approaches were identified: 1. Keep RWC’s existing system, but automate/reduce the need for maintenance. 2. Design a new system that removes the need for maintenance.

Figure 5.3.1: First Flush System Design Approach.

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CP-CBU-125 Figure 5.3.1 shows how each design attempts to solve the maintenance problem. Only designs selected for prototyping are discussed here. For information on other designs refer to Appendix B2. As a maintenance free design was pursued, the Project Team simultaneously explored the educational solutions available and these are included in Section 7.

Canvas Bag This design fits into the first category listed above under ‘First Flush Design Process’. It is identical to RWC’s current fixed volume ball valve system described in Section 5.3.2, but replaces the problematic drip-hole with a porous material bag. Water weeps through the bag to reset the system. As there is no hole to become blocked, the system will theoretically function even with a build-up of debris. Although maintenance will eventually be required, it will extend the maintenance free period considerably. By the time the sludge build up becomes an issue, the bag may have decomposed, in which case the bag should be removed and replaced. This is potentially advantageous in that it will be obvious when the bag fails, as no water will reach the tank, whereas currently the problem is out of sight with rainwater continuing to fill the tank when the drip-hole is blocked.

Figure 5.3.2: Canvas bag design, with quick release fastening mechanism.

Table 5.3.1: Canvas bag design, advantages and disadvantages. Advantages Direct way of controlling volume to be diverted. Can be readily implemented on existing systems Simple Design. Is hoped to reduce need for maintenance.

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Disadvantages Does not remove need for maintenance. Bag will need replacing eventually.

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CP-CBU-125 Angled First Flush Wastage flow-rate is defined as the flow rate through the drainage-hole of a first flush-system when full (i.e. during a rain event). The wastage flow-rate of RWC’s existing system was higher than expected (see Appendix B12), causing householders to block the drainage-hole to save water (see Section 7.5.2 for details of discussions with householders). This design attempts to reduce the wastage flow-rate without decreasing the size of the hole. It is identical to the existing system, but instead of hanging straight down, the first flush chamber is angled, as illustrated in Figure 5.3.2. This reduces the pressure head and hence flow-rate, whilst keeping the first flush volume and size of the drainage hole constant. Alternatively, the size of the hole could be increased, keeping the flow rate the same but making it less likely to block. For a full analysis of the system refer to Appendix B11.

Figure 5.3.3: Angled First Flush Design.

Table 5.3.2: Angled First Flush Design, Advantages and Disadvantages. Advantages Almost identical to existing system – easy to implement, no new parts required. Gives control over flow rate other than through hole-size.

Disadvantages Will still block eventually. Still requires maintenance.

Chlorine Filter This design is a simple modification of RWC’s existing design that aims to reduce maintenance by making the drainage hole less likely to block. The drainage hole is moved from the side of the down-pipe to the centre of the cap, where it is covered by a thin vertical pipe perforated by many smaller holes, somewhat like a chlorine filter. There is an unperforated band of pipe along the bottom to allow a build-up of sludge on the cap without it reaching the drainage-hole. The system is shown in Figure 5.3.4. Final Report 2012

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Figure 5.3.4: Chlorine Filter.

Table 5.3.3: Chlorine Filter, Advantages and Disadvantages. Advantages Almost identical to existing system. Only cap needs to be modified from existing system, rest of system need not be changed.

5.4

Disadvantages Will still block eventually. Still requires maintenance.

Selection of Concept and Existing Designs for Prototyping

Some of the criteria established in Table 5.1.1 are interlinked and do not lend themselves to a simple numerical scale. Scale factors were therefore created to cover each criterion and were designated an appropriate weighting. These factors were used to select designs for prototyping. Each design was assigned a value ranging from one to five for each factor, with five being excellent and one being poor. For the new designs, and some existing designs that had not been well documented, it was difficult to assign values with confidence. The grading system was used again after prototyping to determine which systems had been the most successful. Table 5.4.1 shows the results of the pre-prototyping evaluation. Appendix B4 describes the process in more detail.

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Table 5.4.1: Pre-prototyping evaluation of all first flush designs. Factor Weight Fixed Volume Ball Valve Tipping Gutter Counterweight Changing Angle Manual Reset First Flush Ball Valve Tipping Triangle Manual Flush Canvas Bag Waterwheel Chlorine Filter

Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std.

Manufactu rability 2 4 8 3 6 1 2 4 8 4 8 3 6 2 4 5 10 4 8 1.5 3 3.5 7

Reliability 3 4 12 3 9 1 3 4 12 5 15 4 12 2 6 5 15 5 15 4 12 4 12

Cost 3 4 12 3 9 1 3 3 9 3.5 10.5 3 9 2 6 5 15 3 9 2 6 3.5 10.5

User Input 4 5 20 5 20 5 20 5 20 2 8 5 20 5 20 1 4 5 20 5 20 5 20

Frequency of Complexity of Maintenance Maintenance 3 4 3 3 9 12 3 4.5 9 18 5 3 15 12 4 3 12 12 5 3 15 12 5 3 15 12 3 2 9 8 5 2 15 8 4.5 3 13.5 12 5 4 15 16 4 3 12 12

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Aesthetic 1 4 4 3 3 3 3 3.5 3.5 4 4 5 5 3 3 3 3 2 2 2 2 4 4

Efficiency (wastage) 2 3 6 3 6 3 6 4 8 5 10 3 6 3 6 5 10 4 8 5 10 3 6

Tot.

Rank

Better than existing?

83

6 N/A

80

7 No

64

10 No

84.5

3 Yes

82.5

8 No

85

2 Yes

62

11 No

80

8 No

87.5

1 Yes

84

4 Yes

83.5

5 Yes

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CP-CBU-125 5.5

Prototyping and Optimisation

Not all designs were selected for prototyping. Those that were are summarised below, including the prototypes constructed and tests conducted on each of the designs. Further information on the prototyping and test procedures can be found in Appendices B5-10. The supporting calculations for any theoretical values and figures in this section are included in Appendix B11.

First Flush Ball Valve Three prototypes were constructed, with each prototype aiming to address issues with the preceding prototype. The first prototype is shown in Figure 5.5.1. It was constructed from a length of 90mm PVC pipe, closed at the bottom with a push-on end-cap. A large hole is drilled through the base. The valve consisted of a ping pong ball sitting in a cistern ring seat, suspended by an elastic band from a threaded shaft. It had a pinhole pushed through the bottom for reset and holes drilled through the top to permit it to fill with water.

Figure 5.5.1: The First Flush Ball Valve prototype 1a.

The prototype was attached to a temporary gutter and subjected to the estimated operational flow-rates shown in Table 5.1.2, via a test regime described in Appendix B5.1. It essentially worked, with the valve allowing the initial flow of water to pass through before closing, directing the remaining water into the tank. The system reset over a period of approximately three hours. Reset time for this system is fairly arbitrary (a larger drainage-hole would have reset faster) but is likely to be similar to that of the current system as the mechanism is essentially the same; drainage through a small hole. The system was very inconsistent, flushing between 1.3-30L (see Figure B5.2.6 in Appendix B5.2). For flow rates below 4mm/hr the prototype flushed indefinitely as the valve never closed. Table 5.5.1 lists issues uncovered during testing, and measures taken to address these issues in the second prototype. More detail into the first prototype is provided in Appendix B5.2. Final Report 2012

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CP-CBU-125 Table 5.5.1: Issues and solutions identified in Prototype 1a. Issue with prototype 1a Ball does not always land in seat when full- it can become stuck outside sealing ring, preventing valve from closing. Cap pops off when pipe is full. Ball fills too quickly under certain circumstances (not enough water flushed). The way water falls through the pipe is unpredictable- in some cases it misses the ball altogether (valve never closes), in other cases it lands directly on ball. Stiffness of elastic bands is unpredictable and difficult to replicate. Pin hole appears to close over with time

Measure(s) to mitigate in prototype 1b  Bigger ball  Bigger hole  Bigger sealing ring     

Screw-on cap Smaller holes drilled into ball Trial different hole sizes Larger ball relative to pipe diameter ‘Diffusor rings’ to make flow more predictable



Replace elastic bands with spring/nylon thread



Larger pin hole

The second prototype is shown in Figures 5.5.2. It was constructed in the same way as the first prototype, with the modifications listed in Table 5.5.1 implemented.

Figure 5.5.2: First Flush Ball Valve Prototype 1b.

The second prototype was an improvement on the first. With one notable exception, around one to two litres were diverted in the majority of tests. Importantly, the valve closed even at extremely low flow rates, due to the inclusion of the ‘diffusor ring’ visible in Figure 5.5.2. However, while it was an improvement on the first prototype, the volume flushed was still inconsistent (See Appendix B5.3, Figure B5.3.8).

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CP-CBU-125 The inclusion of a fine mesh over the input holes to the ball was trialled, with the intention of preventing debris from entering the ball and blocking the drainage-hole. The modified ball is shown in Appendix B5.3, Figure B5.3.5. However, after being left outside for a period of days, both mesh and drainage hole were clogged with debris. The clogged drainage hole prevented the system from resetting, rendering it useless. This is consistent with the one independent review of a First Flush Ball Valve device the Project Team was able to obtain. A user who had tried two commercial devices wrote that “it is all too easy for [the drainagehole] to become obstructed with small particles ... The ball then does not drain properly and the device does not reset itself. Thus, both devices required close monitoring and frequent manual cleaning in our system.” [64] While testing the second prototype, it was observed that the elastic material used as a spring expanded and became slack when wet. It did not function as a spring in this state, but the system still worked. The ball bobbed up and down in its seat, allowing water to be flushed, until it was full and no longer floated, closing the valve as normal. The third prototype dispenses with the spring altogether, instead ‘skewering’ the ball on a metal shaft, as shown in Figure 5.5.3. The ball slides along the shaft as it bobs up and down while flushing water. The prototype was not tested extensively, but appeared to be effective. It is discussed in more detail in Appendix B5.4.

Figure 5.5.3: Third First Flush Prototype

Canvas Bag Several materials and fastening mechanisms were trialled with this design. Tests into wastage flow-rate and reset time were conducted in Melbourne, and field tests were conducted in Cambodia. Appendix B6 gives a full account of the prototyping, testing, and optimisation conducted. Three materials were tested for porosity: Canvas waterbag material, artists’ canvas, and denim. A circle was cut from each material, and fastened to a length of 90mm PVC pipe with a screw-clamp, as shown in the first panel of Figure 5.5.4. The downpipe was then filled with water. Final Report 2012

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Figure 5.5.4: Canvas waterbag material porosity testing and field-testing.

Two of the three materials tested, namely artists’ canvas and denim, drained too quickly. The waterbag canvas material was more promising, however, its thickness and stiffness prevented the fastening mechanism illustrated in Figure 5.5.4 from being effective. The majority of water spilled out the top of the bag, escaping through the folds in the material, rather than weeping through the material itself. This problem was solved by sewing a rectangle of waterbag canvas into a bag that fit firmly over a 90mm pipe (second panel of Figure 5.5.4). The flow rates for the canvas bag design were much more reasonable, and it was deemed worthy of field-testing in Cambodia. The second panel of Figure 5.5.4 shows the canvas bag fitted to RWC’s existing system at their office, where it replaced the end-cap and drainage hole. It had a reset time of roughly eight hours, an enormous improvement on the existing system’s ten-minute reset time. The canvas bag was left in place when the Project Team returned to Australia, so that RWC staff can monitor it over a longer period of time. This was done to assess whether it deteriorates and whether it is able to handle debris without blocking.

Changing Angle Prototyping and testing of the Changing Angle design was conducted at RWC’s office in Cambodia, using their existing system. For further information, see Appendix B8. Preliminary testing was conducted to measure the effect of varying the angle on wastage flow-rate and reset time; and to check that the ball valve still functioned at an angle. The measured wastage flow-rate at each angle tested is compared with the theoretical flow rate in the first panel of Figure 5.5.5. It is expressed as a percentage saving relative to the existing system in the second panel. The maximum achievable angle before the ball valve stopped sealing properly was sixty degrees. This permits a theoretical saving of thirty percent, however, the measured saving at this angle was forty percent. Final Report 2012

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Figure 5.5.5: Wastage Flow-Rate and Percentage Saving vs. Angle

A prototype was constructed from parts already available at RWC that enabled the existing first flush chamber to be positioned at any angle, shown in Figure 5.5.6. The flow-rate slowed visibly at higher angles. It should be noted that due to the small length of vertical pipe between the first flush chamber and the main horizontal pipe, the pressure head for this prototype will always be slightly higher than the theoretical pressure head for a given angle. This means that the wastage flow-rate will be slightly higher, reducing the savings.

Figure 5.5.6: Angled first flush prototype.

Design charts are provided in Appendix B15 to assist RWC with the implementation of this scheme. The charts can be used to determine the wastage flow-rate and reset time for a given drainage-hole diameter and first flush angle, or to determine candidate hole-size/angle combinations to achieve a desired flow rate or reset time.

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CP-CBU-125 Chlorine Filter Testing of the Chlorine Filter design was also conducted at RWC’s office in Cambodia. More detail on the prototyping and testing of this design are provided in Appendix B10. A simple prototype, shown in the first panel of Figure 5.5.7, was constructed from a standard end-cap in RWC’s existing first flush system. A hole was drilled through the bottom of the cap, over which the ‘chlorine filter’ (a length of small pipe with holes drilled through it) was glued.

Figure 5.5.7: ‘Chlorine Filter’ Prototype and Alternative Fastening Mechanism.

A major advantage of this design is that it can be fitted to existing systems simply by replacing the end-cap. Extensive testing was not conducted due to time constraints, however, the system did not block when a large amount of dirt was flushed into the chamber along with water. RWC’s existing system did block during the same test. Unfortunately, the ‘chlorine filter’ was dislodged when the end-cap was removed. The second panel of Figure 5.5.7 suggests an alternative, more robust, means of attaching it to the end-cap.

5.6

Post-Prototyping Evaluation and Comparison

After prototyping and testing, it became apparent that some of the values assigned to many of the designs in the pre-prototype evaluation (Table 5.4.2) were unrealistic. Table 5.6.1 shows the updated evaluation. A full breakdown of what changed and why is given in Appendix B13. Most notably, the First Flush Ball Valve was not as effective as hoped, and the existing system was less efficient than previously thought.

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Table 5.6.1: Post-Prototype Evaluation Factor Weight Fixed Volume Ball Valve Tipping Gutter Counterweight Changing Angle Manual Reset First Flush Ball Valve Tipping Triangle Manual Flush Canvas Bag Waterwheel

Chlorine Filter

Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std.

Manufactu Reliability Cost User Frequency of Complexity of Aesthetic Efficiency Tot. Rank rability Input Maintenance Maintenance (wastage) 2 3 3 4 3 4 1 2 4 4 4 5 3 3 4 2.5 8 12 12 20 9 12 4 5 4 82 3 3 3 5 3 4.5 3 3 6 9 9 20 9 18 3 6 80 6 1 1 1 5 5 3 3 3 2 3 3 20 15 12 3 6 64 10 4 4 3 5 3.5 3 3.5 3.5 8 12 9 20 10.5 12 3.5 7 4 82 4 5 3.5 2 4.5 3 4 5 8 15 10.5 8 13.5 12 4 10 2 81 3 2 3 5 2.5 3 5 3 6 6 9 20 7.5 12 5 6 71.5 9 2 2 2 5 3 2 3 3 4 6 6 20 9 8 3 6 62 11 5 5 5 1 5 2 3 5 10 15 15 4 15 8 3 10 80 6 4 5 3 5 4.5 3 2 4.5 8 15 9 20 13.5 12 2 9 88.5 1 1 1 2 5 5 4 2 5 2 3 6 20 15 16 2 10 74 8 3.5 4 3.5 5 4 3 4 2.5 7 12 10.5 20 12 12 4 5 82.5 3

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Better than existing?

No No Same No No No No Yes No Yes

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5.7

Sizing the First Flush

The size of RWC’s First Flush system was analysed using the method described by [26] in the Literature Review section of this report. This method recommends that for every mm flushed, the contaminant load will halve. Table 5.7.1 shows the results of this analysis and Appendix B1.2 shows how to apply this method and how the results were obtained. RWC currently removes the initial 10.5 litres of rainfall in the first flush system for Concrete Ring tanks and Jumbo Jars. The institutional systems are much larger and vary from system to system, but flush on average 140 litres.

Table 5.7.1: First Flush parameters, current sizing and recommended sizing based on analysis. Parameters

Jumbo Jar

Initial Turbidity (NTU) Turbidity at Entry to Tank (NTU) Roof Area (m2) Current amount of Rainfall to flush (mm) Recommend amount of Rainfall to flush (mm) Current Volume Flushed (L) Recommend volume of First Flush system (L)

1000 20 25 0.42 3.5 10.5 85

Concrete Ring Tank 1000 50 25 0.42 2 10.5 50

Institutional System 1000 50 100 1.41 2 140 200

The analysis shows that all first flush systems currently in use by RWC are undersized and may be adversely affecting the water quality produced by the RWH system. The Jumbo Jar is the most undersized system. Based on this analysis systems with a Jumbo Jar installed should have a first flush system with an 85L volume. This is extremely large, although it is not so large as to be cost prohibitive. A change to first flush systems of this size would present physical challenges of installing the system in small spaces in households, as well as a marked increase in the amount of water perceived to be ‘wasted’ by the household. The Concrete Ring Tank requires a smaller increase in volume to meet the recommendations in the literature. This increase is quite feasible with a larger diameter pipe, although the increase in weight and pressure head (due to height increase) would need to be considered. Options to minimise the weight, pressure head and flow-rate of the first flush system are discussed further in Section 5.5. The institutional systems are proportionally the closer of the three first flush systems analysed using the literature recommendations. A further 60L increase is quite feasible and many institutional systems have already achieved this value by the installation of two first flush systems, one for each side of the house as shown in Figure 5.7.1.

CP-CBU-125

Figure 5.7.1: An institutional system with two first flush systems installed, one for either side of the house.

5.8

Cost Analysis for Modifications to Existing System (Angled First Flush and Canvas Bag Designs)

The cost of each of these modified first flush systems (compared with no first flush system) was calculated by assigning a monetary value to water, and determining the quantity of water ‘wasted’ by each design. A value of 0.003 $USD/Litre was reached, based on the average wage and distance to water of households in Cambodia. The amount of water ‘wasted’ annually by each first flush filter was calculated based on rainfall data, flushed volume, and wastage flow-rate recorded for each design. Water is ‘wasted’ in two ways. The first is the volume emptied from the first flush chamber at the end of each rainfall event. The second is the water that streams out the bottom of the first flush while it is raining (wastage flow-rate). The total water ‘wasted’ is therefore the sum of wastage during rainfall, and wastage after a rainfall event. The cost of each system is shown in Table 5.8.1. The angled first flush can save close to 50% of the cost of wasted water, while the canvas bag can save close over 90%, relative to the current design. Appendix B14 shows the cost analysis in detail.

Table 5.8.1: Results of CAPEX Analysis of Angled System and Canvas Bag

Annual Cost During Rainfall Annual Cost Emptying TOTAL ANNUAL WASTAGE

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Existing System Angled System (60°) Canvas Bag $70.73 $33.47 $1.08 $9.63 $9.63 $4.79 $80.36 $43.1 $5.78

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6. Tank Solutions 6.1 Analysis of Alternative Tank Designs The Project Team conducted extensive research into existing low cost water storage tanks from around the world. A list of the tanks analysed is included in Appendix C3.1 and a brief description of the each tank is included in Appendix C1. The tanks were then compared to a set of Basic Design Requirements (BDR’s) compiled in collaboration with RWC, to assess the suitability of each design to RWC. The BDR’s are included in Appendix C2.1 and list of tank designs checked against these BDR’s are included in Appendix C4.1. The remaining tank designs were rated using a set of Optimisation Criteria (OC) developed in conjunction with RWC and EWB Field Engineer James Oakley. These OC are used to compare the remaining alternative tank designs to each other and to RWC’s existing system. The OC incorporate a thorough cost analysis conducted by the Project Team whilst in Cambodia, with the assistance of RWC staff. The results of this comparison are shown in Table 6.1.1. The full cost analysis for each tank can be found in Appendix C9. Table 6.1.1: The final scores of the alternative tank designs analysed by the Project Team. Tank Concrete Ring Tank Jumbo Jar Tarpaulin Tank Pumpkin Tank Interlocking Block Tank Semi-Submerged Dome Tank Closed Frame Ferro-cement Open Frame Ferro-cement Plate Tank Above Ground Mud Tank Large Partially Underground Dome Tank Single Skin External Reinforced

Total 48 50 54 51 41 47 47 47 41 45 52 53

The Tarpaulin Tank design scores the highest of the alternative tank designs. Details on the Tarpaulin Tank can be found in Appendix C1. The tank is deemed the most appropriate of the alternatives analysed and was selected for construction in Australia by the Project Team. Other high ranking designs which could be suitable to substitute the existing tanks were the Pumpkin Tank, the Large Partially Underground Dome Tank and the Single Skin Reinforced Tank. The construction manuals, if they were available for these tanks, can be found in Appendix E.

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Figure 6.1.1: The Tarpaulin Tank which was developed in Uganda [65]. The most promising tank design for large storage which could substitute the tanks currently used in institutions is the Large Partially Underground Dome Tank. The Tarpaulin Tank design is also theoretically scalable to the 10,000 litre size, although the durability of the design remains to be tested. RWC Director Kea expressed specific interest in locating an alternative, lower cost, large scale tank design to replace the institutional system, which are currently cost prohibitive for many communities. The Single Skin Externally Reinforced tank scored very high in the rating system. This suggests the design is worth exploration by RWC to determine if it could be included in the tank packages they offer.

Figure 6.1.2: Single Skin Externally Reinforced Tank [66]

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CP-CBU-125 The Pumpkin Tank design also scored quite highly, just ahead of the Jumbo Jar due to lower construction costs. This is as expected as the tanks are almost identical in design. The difference is in the slightly better surface area to volume ratio of the Pumpkin Tank, due to its near spherical shape, which results in lower materials costs. A further improvement on the Pumpkin Tank design would be to move to spherical tanks. Although very little literature exists on the construction of spherical tanks, the Project Team have been in contact will an NGO in Phnom Penh who construct spherical tanks. The NGO is Resource Development International Cambodia (RDIC). The tanks are made in a similar fashion to the Jumbo Jars, using wire mesh and ferro-cement. The spherical tanks are currently distributed to the public in much the same way RWC conduct their program. Collaboration and sharing of information between RDIC and RWC is a logical next step in the optimisation of RWC’s RWH tank systems.

Figure 6.1.3: Spherical tanks produced by RDIC in Cambodia. Note the base and the car tyre to indicate the relative size of the tanks

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CP-CBU-125 6.2 Alternative Tank Design Prototyping and Testing The Tarpaulin Tank design was selected for prototyping by the Project Team as the results indicated it was the most appropriate alternative design for RWC. The tank was constructed from locally available materials on a property in rural Victoria, Australia. The original construction manual, included in Appendix E1, was used as a guide. The tank took two people a day to construct and was capable of storing around 2000 litres of rainwater. The tank construction was highly successful and is still functioning perfectly after three months of use. A full construction manual, complete with issues encountered and recommendations for improvement, is included in Appendix E2. The tank was constructed in high quality organic soil with moderate amounts of clay. As with any below ground or semi-submerged design the soil type is critical to construction. The soil was found to be adequate for the tank construction, although care had to be taken with the amount of water added to prevent the soil becoming slurry and affecting the strength of the wall sections. Soil with a higher clay content is ideal for the tank design.

Figure 6.2.1: The Tarpaulin Tank constructed by the team in rural Victoria, Australia.

The tank was constructed using a readily available Polyethylene (PE) coated plastic woven tarpaulin. Ideally the tarp used would be a one piece PE tarpaulin often used in dam construction. These tarpaulins are much stronger, less prone to tearing and much less prone to leaking over time when compared to the PE coated woven tarpaulin. The wood required for construction was from locally felled trees on the rural property, hence were obtained free of charge. 2mm wire was used in the construction of the fame and scaffolding sections. The construction of the Tarpaulin Tank was successful and the tank is currently being monitored by the Project Team. The design is considered viable and appropriate for construction in developing communities such as rural Cambodia. CP-CBU-125

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CP-CBU-125 6.3 Analysis of Existing Tank System Issues As outlined in Table 1.1, RWC initially presented the Project Team with the issue of the leaking cleaning valve at the base of the large tanks. This can be seen in Figure 6.3.1. The seal between the PVC pipe and cement wall is leaking, due to imperfections in the seal combined with high water pressure.

Figure 6.3.1: The leaking cleaning valves at the base of the tank.

Initial research into seals of this type found that a hydrophilic sealant was normally used as an industry standard. Discussions with Niruma Ahkter, an experienced water engineer from ARUP, confirmed this finding. Unfortunately, hydrophilic sealants are not readily available in Cambodia, so the Project Team was required to think creatively in solving this issue. Figure 6.3.2 shows the proposed design solution. The Project Team proposed a change to the location of the cleaning valve. The valve would be moved to the top of the tank, reducing the water pressure on the PVC-cement bond to only a few centimetres of pressure head. An additional feature to this design is the ability to automatically clean the sludge which settles to the bottom of the tank. As the water level rises above the outlet when the tank is full, water is sucked from the bottom. This allows the sludge and lowest quality water to be removed in when overflowing, rather than the high quality water on the surface. The design is quite similar to an overflow arrangement shown in [26], although the reasoning behind the design is quite different. The design combines the release valve and the overflow valve into one, minimising costs and increasing the quality of water stored.

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Figure 6.3.2: Schematic of Proposed Overflow Arrangement

6.4 Prototyping Solutions to Existing Tank Issues and Testing The piping solution to solve the leaking cleaning valve was constructed at RWC’s workshop in Phnom Penh, Cambodia. Figure 6.4.1 shows the piping design constructed in an oil drum of 200 litre capacity. Tests were run to see if the system would automatically clean the base of the tank when the water level reached the overflow pipe. Videos of these tests are included with the electronic submission and are listed in Appendix M. The system successfully cleaned the bottom of the tank. The technical drawing of the system is included in Appendix C5. Initially a separate piping system, complete with valves was designed to allow the tank to empty completely for maintenance. Based on discussions with the local community, RWC staff and observations of local residents ‘homemade’ systems, this extra piping system can be fully replaced with a cheap siphon hose. Local residents entirely understand the siphon system and similar siphon systems are in use in the community already. The siphon hose would be directly attached to the overflow pipe and flow into an existing Pbeng Jar, a common low cost arrangement implemented in the villages.

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CP-CBU-125 Overflow Berries sucked from bottom of test tank

Drainage Figure 6.4.1: The proposed design solution to the leaking cleaning valve issue.

Figure 6.4.2: The overflow arrangement used to solve the leaking cleaning valve issue.

6.5 Analysing Alternative Filter Systems Another of the issues outlined in Table 1.1 by RWC regards the current leaf filter. The current leaf filter is not being cleaned regularly, leading to the system clogging up and often the filter being removed by the residents. Figure 6.5.1 shows the current leaf filter design, which is included in line just before the entrance to the first flush in the current RWH system. For more information see Appendix A8. Research was conducted into leaf filters by the Project Team and a summary of this research is included in the Literature Review section of this report. The Open Environment filter and Chain filter were selected for prototyping based on the simple, low cost design and the appropriateness of the design to the Cambodian context.

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Figure 6.5.1: The current inline leaf filter. The Chain Filter design is shown in Figure 6.5.2. The concept uses the capillary effect of water to guide the stream down a chain. In the process large particles fall out of the water stream due to gravity effects and the chain acts as a large particle filter. Although not technically a first flush system, the chain prototype was tested with the other first flush filters and further information can be found in Appendix B9.

Figure 6.5.2: Basketball Chain Design.

6.6 Alternative Filter Systems Prototyping and Testing The Open Environment leaf filter was constructed on a rural property in northern Victoria, Australia. The basic Open Environment filter design is included in Figure 6.6.1. The design has functioned reasonably well over a period of 6 months with high levels of rainfall. The filter needed some manual cleaning although the majority of debris was removed automatically by the systems sloped design. The pipe is covered with shaped 1mm chicken mesh with 15mm spacing. CP-CBU-125

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Figure 6.6.1: The basic Open Environment Leaf Filter prototype constructed by the Project Team in rural Victoria, Australia. The design was not tested in Cambodia due to time constraints. However, RWC Director Kea has plans to construct a similar Open Environment filter that he discovered in a RWH system in Australia. The chain design was constructed at RWC’s workshop in Cambodia to test its reliability in the field. Only a basic model using a single chain was constructed and tests were carried out. These tests are shown in Appendix B9. The result was the ‘basketball chain design’ shown in Figure 6.5.2. This design was never constructed due to time constraints but a construction diagram was left with Mr Van, the on-site technician at RWC. The plans were discussed and the Chain design is scheduled to be built and trialled in November or December, 2012.

Figure 6.6.2: The initial Chain prototype, to later be replaced by the ‘Basketball’ design. CP-CBU-125

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7. Education 7.1 Background Community engagement is a very important aspect of any humanitarian development project. It is imperative that engineers engage with the community in a manner where the knowledge and voice of all sub-groups are represented. Utilising this varied knowledge and expertise enhances the ability to achieve the proposed outcomes. Community engagement involves communication and empowering all stakeholders. It is about minimising the risks involved to the community and ensuring that the needs are met. As such, it was vital for the Project Team to be educated about the social and cultural context of rural Cambodia. It is extremely beneficial for future groups and individuals who will be working with communities in Cambodia, particularly with RWC, to have a sound understanding of this context. The education aspect of the project recognises this and during the trip to Cambodia, the Project Team conducted research to identify specific relevant areas. The Project Team had two main objectives: 1. To gather information for RWC 2. To gather information for future groups and individuals Research through the form of interviews and discussions were held with members of RWC, residents from the Village of Kraingserey, a health centre and a school. Topics ranged from the benefits of access to clean water, technical issues of the rainwater harvesting system through to the issues and challenges the organisation regularly encounters. 7.2 Education Objectives Areas of focus were developed for the two main objectives. The list below outlines the areas of focus for the two objectives. Objective 1: To gather information for RWC.    

Investigate any technical issues with the tanks and system. Investigate the benefits of the rainwater tanks. Investigate the impact of the hygiene and sanitation programs. To identify learning and teaching styles.

Objective 2: To gather information for future groups and individuals. In addition to the list above:  Identify all issues RWC faces.  Identify what RWC would like the next group to do.  Identify in detail RWC’s education program, the successes, failures, issues.  Determine the whether or not sanitation and hygiene programs are practiced in the village, school and health centre  Determine if maintenance of the rainwater harvesting system is conducted, and who are the individual(s) that are responsible CP-CBU-125

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CP-CBU-125 To meet the initial aim of ‘assisting RWC with their education program’ (as discussed in Section 4), a translated copy of the materials which were provided to the villagers by RWC was obtained, and is shown in Appendix D1. These materials were reviewed and a revised education pamphlet was designed (as shown in Appendix D 11). In addition an education model was designed and built that aims to help convey the importance of maintaining the system. The design can be seen in Appendix D12. Research on the different learning and teaching styles was conducted and a summary booklet is included in Appendix D2. The booklet includes suggestions and ideas for various teaching methods, was produced and has been given to RWC during the field studies in Cambodia. This booklet also suggests ideas to convey messages in a different form, including strategically placing stickers above components that require maintenance.

7.3 Research Objectives The Project Team created a revised questionnaire designed to meet the new objectives. The questionnaire (in Appendix D 4) had four target audiences; 1. 2. 3. 4.

Villages Health centres Schools RWC

Objectives for each target audience were created in order to guide questions and ensure that specific information was obtained during the research in Cambodia. Table 7.3.1 summarises the objectives for the four target audiences.

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CP-CBU-125 Table 7.3.1: Objectives for the target audience of the research Target Audience

Objectives

1. To determine what the water from the rainwater tanks are being used for 2. To identify the impact of having access to clean water Households 3. To determine if the households are practical good sanitation practice (e.g. boil water) 4. To determine if there are any issues with the tanks 1. To identify the sickness that causes the highest number of visits to the health centre. Health 2. To identify if the health centre educates their patients about hygiene and water Centre 3. To identify if the if the tank is maintained, and who is responsible for maintenance 4. To determine if there are any issues with the tanks 1. To identify if the school teaches sanitation and hygiene gain an insight into what they learn about hygiene and water 2. To identify whether children are able to motivate and teach their parents about School what they have learnt 3. To identify if the if the tank is maintained, and who is responsible for maintenance 4. To determine if there are any issues with the tank 1. To identify in detail RWC’s current education program 2. To determine all parties that are involved with the education aspect of RWC 3. To identify the successes, failures and issues associated with the education program RWC 4. To identify RWC’s opinion on the locals attitudes and values with regards to rainwater harvesting and rainwater. 5. To determine issues RWC encounter 6. To determine what work/projects RWC would like future groups to work on

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CP-CBU-125 7.4

Research in Cambodia

Data and information was collected through structured interviews and informal discussions. The team visited a health centre, a school in Phnom Penh, and RWC. Setting The study was conducted in Phnom Penh Cambodia and the Village of Kraingserey (data collection took place between 16 th September 2012 and 20 th September 2012). Participants In total, 9 participants were involved in the research project, consisting of:    

4 formally interviewed from RWC (the executive director, engineer, and 2 program officers) 3 informally interviewed from the Village of Kraingserey 1 informally interviewed from a health centre (the director of the health centre) 1 informally interviewed from a school (the principal)

Translation and Piloting The interview guides were initially prepared in English and reviewed by Associate Professor Jim Black from the Nossal Ethics of Global Health for content and cultural acceptability. The interview used simple language containing both closed and open questions and was carefully structured to not lead the participants in their answers. The questions for the informal interviews were translated by a translator from RWC. However, there was no need to translate the questions into Khmer for the structured interviews, as all the members of RWC had a basic understanding of English. The structured interviews ran for approximately 45 minutes to an hour, and were all located at RWC’s head office in Phnom Penh. The informal discussions varied from 30 minutes to an hour, and were all located at the participant’s house/working location. Analysis Participant answers from the structured interviews were transcribed directly into a field research data book. Quotes from the unstructured and informal conversations were directly recorded onto a digital device. Appendix D5 lists the notes and information that was collected during the interviews and discussions. Limitations A significant limitation to the study was the limited number of participants, with the majority being employees from RWC, The study’s limitations also centred around cross-cultural

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CP-CBU-125 research and the complications arising from translation, language and differences in cultural norms. For the informal interviews, the questions were conducted in English and translated into Khmer by members of RWC. The back-and-forth translation from English to Khmer in addition to the Khmer translator not being fluent in English made the informal conversations difficult as the participants were not asked the correct/intended question. The open-ended questions allowed participants to give unprompted responses, however due to the language barrier and translation difficulties, questions were partially understood by participants and at times considered vague. A more direct line of questioning is recommended for future studies with a translator who is fluent in English and Khmer. Detailed proceedings of the research can be found in Appendix D6.

7.5 Summary of Findings A summary of the findings and information collected from RWC, the health centre, the school and from the villages are listed below along with the specific objectives for the target audience as listed in Table 7.3.1. 7.5.1 RWC RWC has eight staff members and five contractors who are taught and trained to build and install the rainwater harvesting tanks. Objective 1: To identify in detail RWC’s current education program The content in RWC’s hygiene and sanitation program follows the national standards of appropriate WASH practices. At present the organisation has designed and implemented a program for communities and villages. The organisation has started designing a program for schools and hopes to implement it by July 2013. All the WASH programs are funded by different organisations. The current WASH program for the community follows a seven step process that can be found in Appendix D7. RWC provides posters and leaflets that have pictures of the process of washing hands, good sanitation and hygiene practice and diseases that could result from drinking contaminated water. These are included in Appendix D 8. RWC has visited and conducted their WASH program in 173 villages. RWC also conducts small-scale programs to educate health centres and schools. Objective 2: To determine all parties that are involved with the education aspect of RWC RWC has a designated employee, known as the program officer, who is responsible for WASH. The content in the WASH programs have been guided by various approaches and methodologies including:  

Community Led Total Sanitation (CLTS) 1111Behaviour Change Community (BCC)

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CP-CBU-125  

Participatory Hygiene Sanitation Transformation (PHAST)

All employees from RWC who are involved with the WASH programs attend multiple training sessions conducted by the Ministry of Rural Development. In collaboration with the Ministry of Rural Development, RWC conducts training for people who are then selected to be involved with the program. RWC trains three members from the district, who are responsible for educating and training three key promoters in each commune, who then train and educate five members from each village. The five members at the village level make up a Village Development Committee. Appendix D9 illustrates this business structure. The Village Development Committee is responsible for conducting the seven step WASH program, while the key promoter reviews the progress and follow ups. In addition it is worth noting that once a month, about twenty organisations that are involved with WASH programs and marketing, meet to discuss their current progress and new findings.

Objective 3: To identify the successes, failures and issues associated with the education program Executive Director Mr Pheng Kea discussed with the Project Team the issues, successes, and failures associated with the WASH programs conducted by RWC. Director Kea stated that the program is more successful for health centres and schools, but not as successful when conducted with rural villages. Below are the summarised reasons Director Kea believes this is so:  The WASH program is not compulsory; as such lack of participation is an issue.  Women and children tend to join the program but not men, consequently a challenge is to encourage men to be involved  Lack of respect the elderly have towards those who facilitate the program “Old men and elderly don’t respect young guys” -Director Kea  Old generation/elderly not wanting to adopt the new practices and change their attitudes towards hygiene and sanitation “Old generation thinking and habit is an issue” -Director Kea  Difficult to change the villagers’ behaviour and attitude. One example includes the villagers not wanting to act to prevent sickness, but rather deal and solve the problem once it has occurred. “rural want to generate income and solve problem once sick, not prevent from sickness” -Director Kea CP-CBU-125

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CP-CBU-125  Lack of knowledge on how to motivate those who are not interested. “Limitation on knowledge of transformation” -Director Kea  Even if the message is delivered and the women choose to build latrines, an issue is that they need approval from their husbands, who usually are not interested. “wife has to get approval from husband, men are decision maker” -Director Kea Nonetheless, despite the challenges and issues, it is pleasing for RWC to see improvement in places where the WASH program has been implemented. Since the program was implemented, RWC has “seen improvement in 300 people build toilet in 18 months”-Director Kea. Objective 4: To determine issues RWC encounter Other issues and challenges that RWC have encountered include:   

  

People stealing the bicycle pumps at schools (these pumps are installed at schools and health centres to assist in pumping the water from the large tanks) The quantity of rainwater collected is only enough to last the year for drinking and cooking (not washing) People don’t purchase the tanks because: - They cannot afford it - They can afford it but prefer to use their money for other things - They are given a limited time to make the payment (as RWC has a time constraint on project work), hence cannot save/earn enough money to purchase the tank during that period Lack of funding, becomes a significant issue that restricts RWC in many areas (e.g. design of the tanks, monitoring and evaluating process) Villagers using alternative water sources (e.g. pond) and placing the contaminated water in the tanks. One of the key issues that the Project Team identified towards the beginning of the project was that villagers were replenishing their tanks with contaminated water by cutting open the pipe. This situation was discussed with Director Kea. He explained that the locals understood the importance and benefits of rainwater, however, due to the easy and convenient access of water, some villagers used the stored rainwater for all purposes (not just for drinking and cooking as instructed), then realised that they had consumed all the water, consequently refilled their tanks with alternative sources of water. “Villagers use rainwater for all purposes then cut open tank and put contaminated water when empty” - Director Kea

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CP-CBU-125 Objective 5: To determine what work/projects RWC would like future groups to work on Director Kea stated that apart from the continuous technical improvements, regular evaluation is what RWC needs. Due to the lack of funding, there is no process in place for regular evaluation of the systems that have been installed. RWC believes that it would be extremely beneficial if the organisation were to be able to identify the technical and social successes, failures and impact of the rainwater harvesting system; so as to be able to improve and use the results for future programs. RWC would like future groups to not only continue the work that the Project Team has started, but also conduct research to obtain the information. A method of evaluation has already been designed, however has not been conducted. As such, RWC would like future groups to conduct this research, or design and conduct research to identify what was mentioned above. In addition, RWC would appreciate if future projects to attempt to find a way to convey the WASH message to those who ignore the message and are not motivated to follow good WASH practices.

7.5.2 Villages There are 61 households in the Village of Kraingserey (Kirivong Commune, Phnom Srouch District), with 25 of the 61 having rainwater harvesting tanks installed. “25 families in the village have four tanks each” - Household 1 RWC have taught and trained three people from the village to become technicians for the tanks. The village has a committee of five people who are responsible to ensure that the tanks are functioning well. United Nations Development Programme (UNDP) created a very large plastic lined pond storage 3km away that stores and collects rainwater as pictured in Figure 7.5.2.1. Pipes lead from the pond to the households of the village, enabling many to have access to rainwater for a monthly cost. The money is managed by the committee who uses it for maintenance. The quantity of water lasts throughout the duration of the wet season. Unfortunately it does run out during the dry season. Families need to seek alternative methods of obtaining water in the dry season. The Project Team visited three households. Household 1 had seven people in the family and had four concrete-ring tanks that were installed in 2005 and 2006. Household 2 had nine people in the family and a jumbo jar tank. Household 3 had eight people in the family and two concrete-ring tanks.

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Figure 7.5.2.1: Collection and storage pond for rainwater Objective 1: To determine what the water from the rainwater tanks are being used for Household 1 and 2 uses the rainwater from their tanks for drinking and cooking. Household 3 uses the rainwater from the tank for drinking and uses rainwater that is collected in a custom jar that does not have a first flush system (Figure 7.5.2) for cooking. Household 2 and 3 stated that the water from the tank last for the whole year (for drinking and cooking only). Household 2 uses the water from the well (200 metres away) for washing, while Household 3 goes to a pond that is located 5 metres behind the house for washing. “Go to pond to wash. It is 5m away” -Household 3

Objective 2: To identify the impact of having access to clean water Before the rainwater harvesting tanks were installed, the households had alternative sources of water. Household 1 collected the water from a pond. The return trip to this water source took 3 hours and a 200L drum of water was collected that would last for one day. The household now uses the 3 hours that would have been used for collecting water for other work and study. “I use the spare time to work and study at health centre” -Household 1 Household 3 collected water from the mountains which was a 1 hour return trip with a queue that could be up to 2 hours long. Similarly to Household 1, this trip was done every day as the quantity of water that was able to be collected only lasted for a day. The household now uses the extra time on agriculture work and taking care of the kids. “With the spare time I do more agriculture and look after the kids more” -Household 3 Since the tanks have been installed, there seems to be an improvement in the health of the household. Household 1 stated that “when I have tank my health and family improve”. CP-CBU-125

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CP-CBU-125 Household 3 has noted that her husband has not been visiting the doctor as often, and that the household has had less diarrhoea since the tanks have been installed. “when get water from mountain more diarrhoea…since tank kids get no diarrhoea” When questioned whether other households without tanks get diarrhoea, Household 3 replied quickly saying that they “always get sick”.

Objective 3: To determine if the households have good sanitation and hygiene practice When asked whether the households drink water straight from the tanks, Household 1 informed the Project Team that they always boil or filter their water before they drink the rainwater, and boil the water before they cook. “UNDP built pond and pipe water system to supply village. We boil or filter rainwater before drinking” Household 2 also boils the rainwater collected from the jumbo tanks and custom jars, stating that “people boil water because NGO educates community”. Similarly Household 3 also boils their water and mentions that they have learnt to boil the water from visits from the NGO who conducting hygiene and sanitation programs. “many NGO come to teach about sanitation and hygiene…all members of the family go to learn sanitation. We take in turns to go…learn to boil from NGO.”

Objective 4: To determine if there are any issues with the tanks During the visit to Household 1, it was identified that the first flush system was not functioning properly. The system had been in place for seven years and over this time, the plastic ball in the first flush system shrunk, thus was not functioning properly. In addition, it was discovered that the seals at the bottom of the tanks had become brittle and consequently could not be removed or maintained. Conversely, Household 2 had no technical issues with the rainwater harvesting system, however the drainage hole was intentionally blocked with a twig (Figure 7.5.3) to prevent water from being wasted when it flowed through the drip hole “I block the hole in the [in the first flush] because it wastes too much water” - Household 2 “I never take the stick out” - Household 2 During the visit to Household 3, there was no first flush system. The household stated that it “broke from the air”, and could not be replaced as the household had no money. CP-CBU-125

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Figure 7.5.2.2: Household 3’s custom jar (left) and an intentionally blocked First Flush System.

Objective 5: Other interesting information When asked about the difference between rainwater and pond water, the spokesperson for Household 1 said “rainwater tastier”. Household 3 stated that she was grateful for having access to clean water, however that doesn’t solve her income problem. “When I receive a tank I am very happy because I get less sick and I know more about sanitation…I have clean water but this does not fix my income problem. I am still very poor”

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CP-CBU-125 7.5.3 Health centre Objective 1: To identify the sickness that causes the highest number of visits to the health centre Approximately 300-400 patients visit the health centre each month with the majority of patients having diarrhoea. A high percentage of those with diarrhoea are under the age of 5.

Objective 2: To identify if the health centre educates their patients about hygiene and water The health centre has implemented a hygiene and sanitation program where they teach and educate their patients about good sanitation and hygiene practices. They have a committee consisting of nine people who conduct the program. Posters and leaflets, received from RWC, have been used as a teaching aid for the committee members, who then use the aids to teach the patients about sanitation and hygiene. These can be viewed in Appendix D 10. Since the program has been implemented, there has been a decrease in the number of people coming to the health centre with diarrhoea “since RWC install tanks there is clean water, less people with diarrhoea” - Director of the Health Centre “After RWC come here more community have more understanding about drinking water and hygiene” - Director of the Health Centre Objective 2: To identify if the tank is maintained, and who is responsible for maintenance The staff members of the health centre are responsible for the maintenance of the tanks. They take turns to regularly check the system.

Objective 3: To determine if there are any technical issues with the tanks The Project Team and RWC were informed that when it rains heavily water flows into the hospital. The Project Team inspected the situation and discovered that the water would flow through the pipe and through an air vent situated above the door, thus flowing into the hospital. A separate issue investigated by the Project Team investigated the issue and discovered that first flush system was blocked. The reason to the blockage was either that the system wasn’t maintained or the outlet pipe diameter was slightly too small for the size of the pipes from the gutters to the first flush and tanks. CP-CBU-125

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CP-CBU-125 Objective 4: Other interesting information The large ferro-cement tank, shown in Figure 7.5.3.1, was installed in 2010 by RWC. A hand washing station, shown in Figure 7.5.3.2, was also installed to ensure that patients and staff are able to wash their hands in a hygienic and convenient manner. The rainwater collected is used for drinking, washing hands and for patients.

Figure 7.5.3.1: The ferro-cement tank installed in the health centre.

Figure 7.5.3.2: Hand washing station at the health centre.

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CP-CBU-125 7.5.4 Schools Objective 1: To identify if the school teaches sanitation and hygiene to the student, if yes, to gain an insight into what they learn about hygiene and water An NGO, known as CSCS, visited the school about three years ago and taught the teachers and students about hygiene and sanitation. Since then the school has adopted a hygiene and sanitation program. The school conducts hygiene and sanitation classes every Thursday for 2 hours, where students are taught correct hygiene and sanitation practices, including washing their hands properly. Students learn by listening to their teachers (verbal teaching), completing booklets (writing), by painting and by the practical application of washing their hands. Posters showing good hygiene and sanitation practice are placed in classrooms and around the school.

Figure 7.5.4.1: Poster conveying the correct process of washing hands.

Objective 2: To identify whether children are able to motivate and teach their parents about what they have learnt When the question was asked of the principal, he responded by saying that the parents teach their children to wash their hands, and that the school teaches the students the correct process. He mentioned that the parents of the children in the school, located in Phnom Penh, are aware that they should be washing their hands as most of them have been educated or exposed to the good hygiene and sanitation practices, unlike most rural areas. Objective 3:To identify if the if the tank is maintained, and who is responsible for maintenance All the teachers are responsible for maintaining the tanks, and a rostering system is in place to ensure this happens CP-CBU-125

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CP-CBU-125 Objective 4: To determine if there are any issues with the tank At the time of the visit, there had been no issues to date with the tank. Objective 5: Other interesting information The tank, shown in Figure 7.5.4.2, was installed in 2011 and holds up to 330 000L of water. The rainwater is used for drinking and washing hands. The tank is directed to two drinking stations and two hand washing stations. Figure 7.5.4.3 illustrates the drinking stations and hand washing stations. Before the tank was installed, water was obtained from water wells which are located on the school property. The quality of the water from the tanks was not safe to drink, so the school had to purchase bottles of water from private sellers, which was quite expensive. “before tank installed, had to pay for water, very expensive” - Principal The rainwater in the tank lasts for 6 months of the year. Water is bought from private sellers for the remaining 6 months. There are approximately 300 students in the school, ranging from the age of 5 to 16 years old. The students do not have to pay to attend school. RWC highlighted that schools that do not have the assistance of a NGO or WASH program cannot implement WASH education because they do not have enough money. Thus the students in those schools are not being educated about sanitation and hygiene.

Figure 7.5.4.2: Ferro-cement tank installed at the school.

Figure 7.5.4.3: Drinking Station (left) and Hand-washing station (right). CP-CBU-125

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8. Conclusions and Recommendations The Project Team recommends the following changes or additions to RWC’s current RWH program, based on the discussions detailed in this report.

8.1 Tank Recommendations The Project Team has a variety of recommendations regarding tank design and filter systems. These recommendations aim to reduce cost and material use, increasing storage capacity, and increase water quality. The solutions also aim to solve the issues of leaking seals and residents adding grey water to the system.

8.1.1 Alternative Tank Recommendations The Cement Ring Tank and Jumbo Jar, currently used as the main medium sized storage systems, are relatively expensive, material intensive and have a comparatively low storage capacity of 3000L. The largest tank used by RWC is of 30,000L capacity which is installed in schools and hospitals. This tank costs between $2,000 and $2,800, which is a very large upfront cost in these communities. The 5000L Tarpaulin Tank design is the most suitable existing alternative tank for use as a substitute for the Cement Ring Tank and Jumbo Jar. The Tarpaulin Tank is 82% cheaper than the Cement Ring Tank and 68% cheaper than the Jumbo Jar based on the cost analysis. Further research must be conducted into the longevity of this design and the ability to scale up the design for use as a large storage solution in schools and hospitals. It is advised that the Pumpkin Tank is also a very suitable substitute. The Project Team networked with an NGO based in Phnom Penh, known as Resource Development International Cambodia (RDIC), who has experience in spherical tanks. Collaboration between RWC and RDIC could be beneficial to both organisations as well as the communities they serve. The 6000L Single Skin Externally Reinforced Tank and the 5000L Semi-Submerged Dome Tank should be field tested as they could also potentially substitute for the Cement Ring Tank and Jumbo Jar. Further field testing must be conducted into the ability to scale up theses designs for use as a large storage solution in schools and hospitals. The Project Group did not prototype these designs and cannot recommend a local NGO with prior field trials. The largest alternative tank design researched by the Project Team is the Large Partially Below Ground Dome Tank, quoted to scale up to 12200L. This tank has the capacity to be used in institutions such as schools and hospitals, especially if further research is conducted into scaling it up to larger sizes. Furthermore, it has the capacity to be implemented as a household tank of varying size due to the ability of this design to be scaled down. It is CP-CBU-125

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CP-CBU-125 recommended that this tank is researched further as the Project Group did not prototype this design and cannot recommend it to a local NGO with prior field trials. The Project Team recommends that it is plausible to have multiple tanks on the market. The recipients of the tanks could choose which design they prefer based on size, cost, aesthetics and reliability. As the workmanship of the alternative tanks improves, costs will reduce and reliability will increase. These factors will increase demand making the alternative tanks more sustainable. The Project Team does not suggest the replacement of existing tanks, rather a transitional period.

8.1.2 Secondary Tank Recommendations The Project Team’s visit to Cambodia revealed some useful information regarding the idea of a secondary tank to store surface water. Originally the Tarpaulin Tank was being investigated as a likely candidate for this secondary tank, due to the low cost of materials and simplicity in construction. Visits to rural communities in Cambodia discovered the use of traditional Pbeng Jars, small versions of the Jumbo Jar constructed by RWC. These jars are already in use in all rural communities in Cambodia, to store any water that is available. The Pbeng Jars store between 100-200 litres, costing from $7.50 to $10 depending on size. The Jars are available in all markets and are made using local materials by local members of the community. Some households had already begun using the Pbeng Jars to store water from the first flush or overflow of their existing RWC system. Given that these jars meet all the BDR’s for alternative tank design and are much cheaper than any of the alternative tanks identified, the Project Team recommends RWC incorporate the Pbeng Jars into their overall RWH strategy. The Pbeng Jars will ideally be used to collect secondary quality water for bathing, cleaning, gardening and feeding animals. The Pbeng Jars would be included in RWC’s system as storage for overflow, first flush and surface water. The secondary tanks would aim to solve the problem of local residents cutting open the pipe to the main tank to add surface water. It is also recommended that the water exiting the first flush is guided into the secondary tank with the purpose of decreasing the perception that the first flush water is being wasted.

8.1.3 Overflow and Cleaning Valve Arrangement Recommendations The current overflow and cleaning valve arrangement is the cause of leaks and a relatively lower quality of stored water. The project team recommends an overflow arrangement shown in Section 6.4. As the tank overflows, the lower quality water from the bottom of the tank, along with sediment, will be automatically cleaned from the tank. This will increase the quality of water stored in the tank while reducing the need to clean the tank. CP-CBU-125

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CP-CBU-125 The outlet of the overflow can be used to empty the entire tank for cleaning purposes. A common hose can be attached to the outlet and the water can be siphoned from the tank until it is empty. This changes the pressure head on the seal to only a few centimetres, effectively eliminating the leaking issue. This overflow system is recommended for all tank systems RWC installs.

8.1.4 Leaf Filter Recommendations Occasionally the leaf filters in the current system get clogged due to the difficulty of cleaning them. One possible design which could reduce clogging is the Open Air Filter shown in Section 6.6. The Open Air Filter has proven to work with simple, minimal maintenance. It is not recommended to be used in conjunction with the first flush system without field testing, as this may waste too much water. A second possible design is the Chain Filter shown in Section 6.6. Further testing and prototyping is recommended to ascertain if the device will function in all conditions.

8.1.5 Further Tank Research Recommendations The Project team suggests the CAD modelling and construction of all recommended alternative tanks for further optimisation. This is an ideal task to be carried out by a student research team next year. The Project Team are consulting with EWB to help produce a project scope for a student research team next year. This analysis, combined with the construction information and cost of the design in Cambodia would allow Director Kea and the RWC staff to make an informed decision. As part of this analysis CAD modelling of the existing tank designs would be conducted, which would be beneficial to RWC regardless of the outcome of the alternative tanks decision.

8.2 First Flush Recommendations The Project Team recommends a number of tested first flush prototypes as well as amendments to the current sizing of RWC’s first flush volume.

8.2.1 First Flush Design Recommendations The main issue expressed to the Project Team by RWC in the initial design brief was that without routine maintenance the existing system was ineffective. In practice, maintenance was often neglected. Another known issue was that some householders were intentionally blocking the drainage-hole with a stick to prevent it from resetting, rendering it useless. CP-CBU-125

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CP-CBU-125 Testing of the existing system in Cambodia by the Project Team uncovered another issue, a much higher wastage flow-rate and quicker reset time than desirable. Based on interviews with householders the Project Team believes that this could be part of the reason some users block the drainage-hole. The sight of so much water being wasted during rainfall could be, perhaps justifiably, disconcerting. As such, designs were judged on their performance relative to the existing system in terms of: 1. Water wastage and level of maintenance required 2. Retention of the existing system’s positive characteristics such as simplicity, reliability, and low user input The Project Team recommends that the Canvas Bag, Chlorine Filter, and Changing Angle designs be investigated further, and that the Manual Reset design currently used by RWC in institutional systems be considered for residential use. All three of the new designs would require further testing as the first step should they be pursued. The second step would be to design a final prototype, made from local materials and manufacturable with the tools and expertise available to RWC, and integrated into the rest of the RWH system. The Canvas Bag is considered the most promising solutions at this stage as the other two designs do not address both points 1 and 2 as comprehensively. The Canvas Bag design is strongly recommended for further investigation. It received the highest score in the post-prototyping evaluation, reflecting its ability to significantly reduce both maintenance and reset time with minimal change to the existing system. The final prototype has been left in place on RWC’s test system in Cambodia, and it is recommended that it be monitored over a longer period to confirm that it reduces blockages and that the bag does not deteriorate rapidly. A locally available, suitably porous material for the bag has yet to be sourced in Phnom Penh. Sourcing such a material would be a priority should this design be pursued. The Changing Angle design also addresses both issues with the current design. However, its water savings are not as dramatic as those achieved by the Canvas Bag, and its implementation is slightly more complex. The usefulness of this design is hinged upon the assumption that a larger drainage hole will block less easily; the Project Team recommends that further testing be conducted to confirm this hypothesis before the design is pursued further. The Chlorine Filter design reduces the frequency of required maintenance, but does not improve level of water wastage. Tests conducted so far have not been extensive, but the initial results are promising; should this design be pursued, further testing into its ability to function with a heavy sludge load would be the recommended first step, followed by longer term testing on a full system to confirm that the frequency of required maintenance is reduced. The Project Team also recommends that the Manual Flush design, currently in use i n institutional systems, be considered for residential use. This system eliminates both unnecessary wastage and the need for maintenance entirely. Its main disadvantage is the high level of user input required. However, based on information gained from village visits, it is CP-CBU-125 73

CP-CBU-125 apparent that the current system is often disused. This may be through lack of maintenance or the intentional blocking of the drainage-hole. Householders who currently block the drainagehole or who do not carry out maintenance would be no worse off with a Manual Reset. Householders who block the drainage-hole with a stick, but remove it intermittently, are effectively already resetting their system manually, and would be better off with a Manual Reset system, as they would no longer need to carry out maintenance. The question is whether the routine but simple manual reset process or the less frequent but more involved maintenance process currently required is more likely to be carried out. Due to the perception that it is less wasteful, the Project Team believes that the Manual Reset may be less likely to be abused. It is not a perfect solution, but in conjunction with an education program could be a worthwhile option to consider. 8.2.2 First Flush Sizing Recommendations The Project Team recommends that NTU testing be carried out on a number of sample systems to assess water quality. RDIC can provide information and assistance on water quality testing procedure if this is required. If the water quality is found to be lower than the Cambodian Drinking Water Guidelines outlined in Table 3.2.1, the following changes are recommended for the size of the first flush system. The size of the first flush system used with the Jumbo Jar should be increased. This may be done by simply using the large diameter pipe employed in the institutional systems to increase volume. A practical solution will probably involve as large a first flush volume as is practical for the specific household. Another option is to include a settling tank, in a similar way to the Concrete Ring Tank arrangement. The first tank in the system then acts as a first flush system. This reduces the size increase necessary for the external first flush system and may even eliminate the need for it entirely. If the settling tank is to be used entirely for flushing and no water is to be drawn from it directly, the volume of the settling tank is the first flush volume. The cheap, available Pbeng Jars are the ideal candidate for this settling tank.

Figure 8.2.2.1: A settling tank first flush system. The raised jar acts as a first flush volume and is tapped (via siphon hose) for secondary water, for use in washing and feeding animals. The lower jar is drinking water quality [26]. CP-CBU-125

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CP-CBU-125 The size of the first flush system on the concrete ring tank should be increased. An increase of 10 to 50 litres is quite substantial, but the Project Team recommends that the largest first flush system practically possible be installed. Further options to increase water quality in the Concrete Ring Tanks are by using the first tank for secondary water as outlined in the previous recommendation. The combination of first flush system and settling tank solution is easily adequate to provide high quality drinking water. If after testing is completed the water quality of institutional systems is found to be poor, the Project Team recommends increasing the first flush volume to 200 litres. This could be achieved via installation of a second system as shown in Figure B.1.2.1 or by simply increasing the size of the first flush volume. The option of using a settling tank to increase first flush storage volume is also viable. The locally available Pbeng Jars are typically 200L in size and would provide a cheap solution to the volume increase. It is vital a lid is used with the Pbeng Jars, so no external contaminants may enter the water storage during the first flush process.

8.3 Education Recommendations Education is a continuous process that is always changing. Understanding the social and cultural context, and involving the community is a large contributing factor for a successful outcome. As such, the Project Team highly recommends future individuals and groups to conduct background research and engage with the community before designing or implementing any project. The Project Team recommends those working with RWC and similar projects should read the education findings from the research conducted in Cambodia before commencing their work. RWC has not had the opportunity to conduct evaluations on the benefits of the RWH system and WASH programs. As such, the Project Team recommends future groups and individuals to design and conduct research that aims to identify information which will be beneficial for RWC. It is recommended that those conducting this research will seek assistance from The Nossal Institute of Global Health. The Project Team also recommends that the ideas regarding different teaching methods, including strategically placing stickers above components that require maintenance, are reviewed, and where possible utilised.

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CP-CBU-125 8.4 Conclusions The Project Team began this project with a list of issues (See Table 1.1) that became design objectives as the scope was defined. The project objectives were to develop solutions for: 1. The lack of maintenance of the RWH system. 2. The high upfront cost of the systems installation. 3. The lack of knowledge and understanding of drinking water quality, hygiene practices and the health risks involved. 4. The failure or poor performance of particular RWH system components (such as the leaf filters, tank seals and first flush system). The Project Team addressed the first issue from both an educational and technical perspective. New first flush and leaf filter systems have been developed in addition to the documentation of residents’ attitudes and behaviours towards system maintenance. The four alternative tank designs recommended reduce the high upfront cost of the system by between 10 and 78%. When combined with savings from the new first flush designs, the result is a system that is on average 40% cheaper to install and maintain. A cost comparison between RWC’s system and the Project Team’s recommended system can be seen in Table 8.4.1. This table compares the two systems over a ten-year period, and assumes that both tanks have a 3000L capacity. It is assumed that the Tarpaulin Tank is replaced on a five-yearly cycle. The comparison assumes that the Tarpaulin Tank and the Canvas Bag prototype are installed. The justification for the cost of wasted water can be found in Appendix B14. Table 8.4.1: Ten year cost comparison of RWC’s existing system and the Project Team’s proposed system System

RWC's

Project Team's

% Saving

Tank

$213.00

Roofing Piping Screens Guttering First Flush Wasted Water Total

$19.50 $8.00 $3.00 $3.45 $16.78 $803.52

$75.18 $19.50 $8.00 $3.00 $3.45 $75.78

65% 0% 0% 0% 0% -352%

$58.72

93%

$243.63

77%

$1,067.25

The Project Team addressed the remaining issues with a series of designs. The newly developed overflow design both increases water quality and solves the leaking seal issue. The Canvas Bag, Angled First Flush and Chlorine Filter designs all improve the performance of the first flush system. The Project team also made recommendations for optimisation of the existing system components, including increasing the reset time and first flush storage CP-CBU-125

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CP-CBU-125 volume. Finally the team prototyped two leaf filters and investigated the role education levels play in the maintenance of the system. Field research into RWC’s WASH education model and residents’ current knowledge of RWH was compiled. This information will allow for better community engagement with RWC’s RWH program in the future, leading to an increase in residents knowledge of drinking water quality, hygiene practices and the health risks involved. The Project Team has recommended two research projects for engineering students to undertake next year. These new projects will build on the research the Project Team completed into tanks and first flush systems. The Project Team has also recommended that evaluations of the benefits of RWC’s RWH system and WASH programs be conducted. The Project Team has consulted with EWB to define the scope of these recommended projects. In summary, the Project Team has fulfilled all design objectives and made a valuable contribution to RWC and to the low cost RWH community. The Project Team is proud to be able to contribute sustainable water solutions in the communities that need them most.

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Appendix A - Rainwater Cambodia’s Existing RWH system A1 Overview The current system employed by RWC is similar to many low cost systems around the world. An overview of the system is covered here and then the components that comprise the system are examined in detail. RWC delivers both domestic and institutional RWH systems. Figure A1.1 shows a summary of the RWH systems installed by RWC. Rainfall

Roof

Gutters

Screens, Debris Filters

First Flush Filter

Screens, Debris Filters

Tank

Tap

Figure A1.1: The components of RWC’s RWH system. Note that screens and debris filters are not used in the current system, but have been in the past. When utilised, the screen and debris filters are between the roof and guttering, between the guttering and the first flush, between the first flush and the tank or as a replacement of the first flush filter.

Figure A1.2: A typical domestic (left) and institutional (right) RWH system installed by RWC. CP-CBU-125

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CP-CBU-125 A2 Sizing the Tank This section is an extract from a file provided by RWC which justifies the size of the installed tanks. Nothing has been edited. This is a step by step justification. Demand side approach C= Consumption per person per day (L)

6.5 L

n = Number of people in household

5 pax

d = Longest average dry period

150 days (5 months)

Storage requirement (L) = C x n x d

4,875 L

This method assumes sufficient rainfall and roof harvesting area. There is also the risk that the dry period is not calculated correctly and does not fully consider the implication of dry season rainfall. It maybe that the system is too big for the capacity of the storage area or there may not be enough water to last through the dry season but this approach can be used as a good rule of thumb.

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CP-CBU-125 Demand and supply side approach (see table and graph below) (also in attached spreadsheet) A Monthly rainfall (mm) data is obtained from meteorology station. Average or low year data can be used B

Supply (L) is calculated based on: A x I x J

A the monthly rainfall data (mm) I the surface area of the rainfall catchment (m²) J run off coefficient which is 0.9 or 0.95 for CI or zinc alum sheeting and depends on how conservative you want to be but this essentially is an estimate of the percentage of water that you expect to capture from the roof as some is lost to the roof material, some splashes off the roof etc. C Cumulative supply (L) is derived from adding the value of each months supply to the total of each preceding months supply D Monthly demand (L) is determined by how many litres per month per household are required eg 975 L represents 6.5L/person per day for a 5 person household E

Cumulative demand (L) is calculated in the same way as cumulative supply

F

Amount stored (L) = C – E

Subtract from the cumulative amount supplied the cumulative amount required (demand) to identify the total amount that could be available to store each month G Cumulative amount stored (L) is calculated the same way as cumulative supply and represents the cumulative amount of rainfall captured minus the cumulative amount to be used We can see that in October the maximum cumulative amount that could be stored is 4,500L H represents the minimum storage that would enable the demand to be met throughout the dry season and is calculated by taking the last amount stored (F) figure that is in positive and subtracts from is the lat figure that is in deficit This same data can be represented in a graph. The graph below shows that as rainfall drops off at the end of the wet season shown by the smaller monthly increases in cumulative supply, the demand is maintained but the cumulative storage declines. We can also see from the graph that in October there is about 4,500 L that is available to be stored The table and graph are usually shown starting with the first month in which supply meets or exceeds the monthly demand. Using a graph it is easy to see how roof harvesting size and demand impact on cumulative storage requirements.

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Table A2.1: Supply v Demand Average rainfall year

May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr annual

Monthly Supply Cumulative Rainfall (liters) supply (av) (liters) (mm) A C B 145.0 1160.0 1160.0 188.0 1504.0 2664.0 235.8 1886.4 4550.4 242.7 1941.6 6492.0 246.4 1971.2 8463.2 240.4 1923.2 10386.4 101.7 813.6 11200.0 16.4 131.2 11331.2 6.6 52.8 11384.0 18.3 146.4 11530.4 27.4 219.2 11749.6 65.8 526.4 12276.0 1534.5

Monthly Cumulative demand demand (liters) (L) D 975 975 975 975 975 975 975 975 975 975 975 975

E 975 1950 2925 3900 4875 5850 6825 7800 8775 9750 10725 11700

Amount Cumulative stored amount (liters) stored (liters) G F 185.0 529.0 911.4 966.6 996.2 948.2 -161.4 -843.8 -922.2 -828.6 -755.8 -448.6

185.0 714.0 1625.4 2592.0 3588.2 4536.4 4375.0 3531.2 2609.0 1780.4 1024.6 576.0

H

4536.4

576.0 3960.4

I Surface area (m2) J runoff coefficient K Daily consumption (l/day)

10 0.8 32.5

6.5

L/pax per day

Figure: A2.1: Average annual rainfall in Phnom Penh

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Table A2.2: Supply side Approach

Method 1

Rainfall data Months March April May June July August September October November December January February annual

Monthly Monthly Monthly Cumulative Rainfall (mm) supply demand storage storage 33.8 675 105 570 570 36.1 722 105 617 1187 113.0 2260 105 2155 3342 146.8 2936 105 2831 6173 164.0 3279 105 3174 9347 203.5 4070 105 3965 13312 215.3 4306 105 4201 17513 197.9 3957 105 3852 21365 46.6 932 105 827 22192 1.3 25 105 -80 22112 0.0 0 105 -105 22007 70 105 -35 21972 3.5 1161.6 Maximum cumulative storage Cumulative storage at end of dry season

22192 21972

Minumum storage capacity required to overcome the dry season

Equal to the difference between the maximum cumulative storage (end of rainy season) and the stored volume at the end of the dry season 20% wastage Theoretical storage volume (L) Theoretical storage volume (m3)

220 44

264 0.264

Method 2

Table A2.3: Demand Side Approach days of secure supply 60 75 90

Daily demand 68.5 68.5 68.5

Theoretical storage volume (L) 4110 5137.5 6165

Theoretical storage volume (m3) 4 5 6

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Theoretical number of cement ring stands 1.7 2.2 2.6

Exact number of cement ring stands (round up to next higher integer) 5 6 7

Real storage volume (m3) 11.9 14.2 16.6

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A3 Roof The roofing is made from corrugated galvanised iron sheeting. This often has to be installed before the RWH system can be put in place as many rural households have existing roofing made from organic materials. This adds to the cost of the system installation and as such is included in the RWH system cost analysis in Appendix A10. The roof is typically 25m2 and is often just one side of a house to minimise costs. The roof is inclined on a 30 degree angle to the horizontal.

Figure A3.1: Organic roofing and replacement corrugated roofing at a 30 degree angle.

The galvanised sheeting normally lasts for 10 years or more, but this can be dependent on the location of the household. A standard sheet available in Phnom Penh is 2.4m x 1.6m and these are cut to length in the RWC workshop as required. Household systems are typically 25m2 and health centres can be as large as 100m2. RWC asserts that this is more than enough surface area for the systems, as the tanks are full in wet season. There has been a minor complaint in the past that the corrugated roof makes the house somewhat hotter in summer than the organic roof. This is considered a small price to pay for high quality drinking water.

A4 Gutters The guttering for the RWH system is folded galvanised iron sheeting in a semicircular arc. The guttering covers the entire edge of the galvanised roof area and as such 5m of guttering is typically used on a domestic system. More gutting is used on a health centre or school system as often both sides of the building will be utilised for catchment area and the roof area is often much larger.

CP-CBU-125 The diameter of the guttering is 200mm for the household systems. The health centres are 250mm in diameter. The guttering is formed on a semi-circular frame and beat into shape. The edges and end pieces are then crimped together and transported to the site. If the site location is a long way from Phnom Penh the guttering can be made on site.

Figure A4.1: RWC’s typical guttering installations.

The gutters are attached to the house using iron bracketing attached with roofing screw or nails. The guttering typically lasts 10 years or more and it is more common for the cheap iron bracketing to fail well before the gutter, often due to rust damage. This is easily replaced by the household at the local market at very minimal cost. Feedback received by RWC from residents with RWH systems installed indicates that the gutters don’t overflow unless they have become blocked with debris. From this it can be assumed that for the current system parameters the gutters are large enough for efficient water conveyance. This is consistent with the Project Team’s initial estimate, based on flow rate calculations in Appendix B1.1.

Figure A4.2: Guttering pipe fittings.

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CP-CBU-125 A5 Piping The RWH system uses Unplasticised PolyVinyl Chloride (UPVC) piping. The pipe is pressure rated to 5.0 bar. DN65 and DN80 are used for downpipes and piping between system components. DN 65 is used for general system piping in the household systems and DN80 in the larger health centre and school systems. DN100 is used for the first flush system in the households and DN150 for the first flush systems in the health centres and schools. Figure A5.1 shows diagrammatically the use of the various pipe sizes. DN65 DN65

DN100 DN80 DN150 Figure A5.1: RWC’s typical piping installations in a health centre (left) and residential (right) system. Note the DN65 on the health centre system is used for the pressure release valve.

It should be noted that these sizes are the international Diametre Nominal standard, but Cambodia uses a different rating system. Pipes in Cambodia are sized based on the outer diameter regardless of the thickness of the pipe. The majority of the pipe used by RWC is rated to 5 bar, which has a thickness of roughly 10mm. Table A5.1 and A5.2 clarify the differences in size and cost of the various pipe sizes in the RWH systems. Also worth noting is that pipe purchased in Australia was incompatible with pipe available in Cambodia. Pipe diameters were close, but not close enough for the corresponding fittings to be used. Some of the blue pipe available across Cambodia is made locally in Kandal province. The rest is imported from Thailand. Some residents dislike the Cambodian made piping, believing it is of lower quality.

Table A5.1: The different pipe sizes and their respective costs per metre. Note that DN stands for Diametre Nominal, or the normal diameter of the pipe regardless of thickness. This is the CP-CBU-125

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CP-CBU-125 industry standard measurement but in general, does not refer to either the inner or outer diameters of the pipe. Table A5.2: A comparison of cost of the Diametre Nominal pipe sizes Diametre Nominal (mm)

Price/metre ($/m)

DN65

1.125

DN80

1.4375

DN100

2.4325

DN150

6.125

Table A5.2: A comparison of the Diametre Nominal pipe size with the Cambodian pipe size, based on the 5 bar pipe used in RWC’s systems. Note this is an estimate only. Diametre Nominal (mm)

Cambodian (mm)

DN65

75

DN80

90

DN100

114

DN150

165

Figure A5.2: Samples of RWC’s different pipe sizes, different bends and junctions used in the pipe network.

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CP-CBU-125 More information about the types of piping available and the relative costs see Appendix A10 and Appendix O - Videos on the electronic submission. Various other diameter piping is used for the range of systems that RWC constructs. 34mm piping (Cambodian) is often used for household system overflow pipes and release valves, as well as other small tank systems that RWC constructs from time to time. 21mm, 40mm and 49mm (Cambodian) piping is also used for a variety of other piping systems. A common use of the 21mm piping in the health centres is for the transfer of water from a header tank to the wash basins as shown in Figure A5.3. 21mm is also used in the residential systems for the same small decanting taps.

Figure A5.3: The wash basins at a local health centre system installed by RWC, showing the 21mm tapping.

The location of each individual project determines how much of the pipe is bought and cut to length in Phnom Penh and how much is purchased at the local market and cut on site. The piping is assembled using a combination of interference fits, acrylic glue, screws and on rare occasions piping tape.

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CP-CBU-125 A6 First Flush Filter The current domestic RWH system uses a first flush system to remove the initial 10.5 litres of water during a rain event. The system, pictured in Figure A6.1, is a basic floating ball type as described in the literature review section of this report. The ball is simply a children’s plastic ball available at the market. The first flush system is inline, between the guttering and tank systems. Notice the difference in size between the domestic and institutional first flush systems, based on the sizing calculations presented in Appendix A2.

Figure A6.1: Domestic (left) and institutional (right) first flush systems installed by RWC.

The institutional first flush system uses a manual release ball valve as shown in the right of Figure A6.1. The staff at both the school and health centre are responsible for the operation of this first flush system. These systems currently work efficiently and are well maintained. The domestic first flush systems use a small reset hole to drain the first flush pipe. This first flush system has experienced some issues with maintenance in the past. Often the small reset hole becomes clogged, rendering the first flush system useless. This is due to either large pieces of debris building up and blocking the reset hole or a lack of manual cleaning causing a build-up of sludge, which then also blocks the reset hole. Figure A6.2 identifies in detail the reset hole where the blockages occur.

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Release Hole

Figure A6.2: The reset hole on the first flush system that is becoming clogged with debris. Figure A6.2 also shows the top of a homemade PVC guide to direct the first flush water that spurts out of the release hole into a Pbeng Jar below. More information on the operation of this guide and the first flush system general can be seen in Appendix O - Videos in the electronic submission.

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CP-CBU-125 A7 Tank There are three types of tank currently used by RWC in their RWH systems. They are of high quality, both in construction and water quality. RWC estimates the tanks have a lifespan of over 20 years, but as the organisation hasn’t been operating that long this is an estimated figure only. The tanks are sized based on rainfall discussed in Appendix A2 and the costs associated with the Jumbo Jar are included in Appendix A10. The first tank is the Jumbo Jar. This tank is used in the domestic systems. Details on the materials and construction of the Jumbo Jar can be found in RWC’s existing construction manual, listed in Appendix O and included in the electronic submission. The Jar is has a 3000 litre capacity and is constructed from cement and reinforcing mesh.

Figure A7.1: The Jumbo Jar tank design used by RWC.

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CP-CBU-125 The second design is the Concrete Ring Tank. These tanks are also used in the domestic systems. The tanks are constructed to hold 3000 litres, although for an extra cost the design can be scaled up by adding extra rings to the tank, increasing the capacity. This involves the construction of two 1500 litre tanks connected in series. The cost of the materials and labour is covered in Appendix A.10 of this report. Construction information is included in RWC’s construction manual which is listed in Appendix O and included on the electronic submission. The concrete ring tank is the favoured of the two domestic tank designs by the rural community. The reasons for this favouritism are unknown.

Figure A7.2: The Concrete Ring tank design used by RWC.

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CP-CBU-125 The third type of tank is the large Ferro-cement tank installed in institutions. The tank is sized according to the needs of the project and is cylindrical in shape, with a pointed roof as in Figure A7.3. The tank has had some issues with leaking near the cleaning seal and these will be discussed further in Appendix A9.

Figure A7.3: The Ferro-cement institutional tank design used by RWC. A major concern RWC has is the addition of greywater to the Jumbo Jars or Concrete Ring tanks by the residents. In the dry season residents cut the pipe above the tank and use this access point to pour low quality surface water into the tank. It is difficult to ascertain whether the residents don’t understand the health risks of such an action, or do understand but don’t have any other option in the dry season when water is scarce. This issue is discussed further in Section 6-Tanks and Section 7-Education.

Residents cut here

Figure A7.4: The section where the residents cut open the pipe and pour surface water into the tank. CP-CBU-125

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A8 Screens and Debris Filters The leaf filter used by RWC is a 1mm wire mesh over a galvanised iron frame as shown in Figure A8.1. RWC have experimented with alternative leaf filter location in the past but without any major success. The system originally incorporated a screen over the entrance to the downpipe, as shown in Figure A8.1. This proved difficult to clean and soon blocked up the system entirely.

Figure A8.1: Originally the leaf filter (left) was included at the downpipe entrance (right) in RWC’s system. It has since been moved. Some systems currently use an inline screen prior to the first flush system, but this has a similar problem and often results in residents removing the entire first flush system altogether. The first leaf filter is currently inline and located just before the first flush system. The second leaf filter location is at the entrance to the tank. This is proving easily accessible for regular cleaning and the majority of the bulk debris is trapped by the first flush system. This leaf filter system is working efficiently but the first flush system, which is now collecting the bulk of the debris, is becoming clogged extremely quickly. Figure A8.2 shows the location of these two leaf filters.

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Leaf filter location 1 Leaf filter location 2

Figure A8.2: The current leaf filter in the current RWH harvesting system.

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CP-CBU-125 A9 Taps and Seals The water is finally removed from the tank via a simple UPVC fitting and then a chrome tap near the base of the tank. The tap is installed during the construction of the tank itself by placing the pipe in the reinforcing mesh, which is then concreted into the tank wall.

Figure A9.1: The tap at the base of the tank from which drinking water is drawn. There is also a UPVC release valve at the base of the tank used for cleaning debris from the tank floor and also to drain the tank for maintenance. An issue RWC are having is that the bond around the UPVC cleaning valve is poor and the tank is leaking very slowly as a result. A similar issue is sometimes encountered around the UPVC fitting for the tap shown in Figure A9.1.

Figure A9.2: The UPVC release valve at the base of the tank used to clean debris from the tank once every 3 months. Note the leak between the UPVC and concrete surfaces. The current method used to clean the tanks was an issue raised by RWC and the EWB Field Engineer James Oakley. The tanks currently require manual cleaning 2-3 times per year, where the release valve is opened at the base of the tank, flushing away the settled debris on CP-CBU-125

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CP-CBU-125 the tank floor. This cleaning in many cases does not happen, causing a built up of debris in the tank, which reduces water quality. There is also an issue of the UPVC fittings deteriorating in the sun over a period of 5 -10 years. This is considered a small issue for the households and these UPVC caps can be obtained from any market for less about $1US. A10 Costs The costs of the RWH system components, installation and maintenance based on a 25m2 roof area. In this section the Concrete Ring Tank is assumed to be the standard 3000 litre size. Costs for maintenance are estimated by consultation with RWC staff.

Table A10.1: Concrete Ring Tank Cost Analysis Materials Cement Sand Aggregate (10mm*20mm) Aggregate (40mm*60mm) Concrete Ring: 1000mm diameter Wire Reinforcement: 4mm PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Unskilled Labour Skilled Labour

Quantity Bags m3 m3 m3 # kg m

Units 3.5 0.5 0.5 0.9 12 4 0.3

Cost/Unit 5 15 26 20 8 2 0.4025

Total Cost $17.50 $7.50 $13.00 $18.00 $96.00 $8.00 $0.12

#

1

2

$2.00

# #

1 2

2 2

$2.00 $4.00

Days Days

3 3

5 10

$15.00 $30.00 Final Cost $213.12

Litres

3000

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Cost per L Cost per LW Labour

$0.0560 $0.0710

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CP-CBU-125 Table A10.2: Jumbo Jar Cost Analysis Materials Cement Sand Aggregate: size 10mm x 20mm Aggregate: size 40mm x 60mm Bar reinforcement: 3mm diameter Wire reinforcement: 1mm diameter PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Skilled mason Unskilled labourer

Quantity Bags m3 m3 m3 Kg Kg M

Units 5.5 0.8 0.2 0.5 1 5 0.3

Cost/Unit 5 15 26 20 1 2 0.4025

Total Cost $27.50 $12.00 $5.20 $10.00 $1.00 $10.00 $0.12

#

1

2

$2.00

# #

1 1

2 2

$2.00 $2.00

Days Days

3 3

10 5

$30.00 $15.00 Final Cost $116.82

Litres

3000

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Cost per L Cost per LW Labour

$0.0239 $0.0389

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CP-CBU-125 Table A10.3: First Flush System Materials Ball Pipe 65mm Pipe 100mm Reducer - 9075mm T Section - 90mm Glue

Units Quantity Cost/Unit # 1 0.3 m 4 1 m 1.5 1.65 # # Kg

3 1 1

Total Cost $ 0.30 $ 4.00 $ 2.48

1 1 6

$ $ $

3.00 1.00 6.00

Total

$

16.78

Table A10.4: Other Miscellaneous Costs Materials Roofing Piping Screens Guttering

Units Quantity Cost/Unit m2 25 0.78 m 8 1 # 1 3 m2 1.57 2.2

Total Cost $ 19.50 $ 8.00 $ 3.00 $ 3.45

Total

$

50.73

Table A10.5: Total System Cost Analysis Materials

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Units Quantity Cost/Unit

Total Cost

Tank

#

1

213

$

213.00

Roofing Piping First Flush Screens Guttering

m2 m # # m2

25 8 1 1 1.57

0.78 1 16.78 3 2.2

$ $ $ $ $

19.50 8.00 16.78 3.00 3.45

Total

$ 263.73

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Appendix B - First Flush System B1

First Flush Design Criteria

The general design criteria for the first flush system are discussed in the Section 5.1 of the report. This appendix provides more detail into how the operational flow rates for the residential system were estimated, how the first flush was sized, and how the optimum reset time was determined.

B1.1

Estimating Operational Flow Rates

To calculate the flow rates from the roof, precipitation rates needed to be established. Precipitation rate is the rate at which rain falls, recorded in mm/hr. This cannot be calculated from monthly rainfall data, which is readily available, as it is concerned with the instantaneous rainfall rate. The rainfall is not distributed evenly across the month – there will be hours or minutes when it is extremely intense, and days when it does not drain at all. Flow rates depend on precipitation rate (sometimes referred to as rainfall intensity), and are unrelated to monthly or annual rainfall. In the absence of precipitation intensity data specific to Cambodia, data from a study of monsoonal India was used [61]. Intensities up to around 70mm/hr. contributed significantly to total rainfall in most of the locations observed in the study, including light rain (<5mm/hr. contributed more than 30% in some locations in certain months). The highest recorded intensity was around 130mm/hour, in two separate instances [61]. Dimensions of the roof areas used were provided by RWC.

(B1.1.1)

Estimated gutter capacity Gutter capacity is the maximum flow rate sustainable by a gutter without overflow. This was calculated, as it places an upper limit on the flow rates that will be experienced by the first flush system. If the flow rate off the roof is greater than the gutter capacity, the first flush system will experience the maximum flow rate sustainable by the gutters, while the remaining rainfall will overflow from the gutters. CP-CBU-125

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CP-CBU-125 RWC uses half-round 200mm diameter galvanised iron guttering. DN65 UPVC pipe is used for the downpipe between the gutter and first flush system. The existing system is discussed further in Appendix A. Marley Alutec estimates the flow capacity of a traditional half round 125mm guttering system with an end outlet to be 1.27L/s [67] (76L/min). FloPlast Estimates the flow capacity of a half round guttering system with an end outlet into 68mm downpipe to be 1.17L/s (70.2L/min) [68]. The maximum flow-rate selected for testing is 50L/min (see Table B1.1.1). RWC’s guttering is larger than 125mm, so should be more than adequate. Although the downpipe is slightly smaller than 68mm, it should still be adequate as the difference is small, and there is a 20L/min margin between the maximum flow-rate for testing and the capacity of a 68mm downpipe. Therefore, guttering is not expected to be the limiting factor.

Representative Flow Rates for Testing Table B1.1.1 shows a range of precipitation intensity’s chosen to be representative of what the domestic system will experience in Cambodia, and the corresponding flow rates, based on equation B1.1.2. (B1.1.2) Where FR=Flow Rate in L/min, PI=Precipitation Intensity in mm/hour, and ERA=Effective Roof Area in m2. Note that none of these flow rates exceed the estimated gutter capacity of the system. Therefore, any new system must function at the flow rates listed in Table B1.1.1.

Table B1.1.1: Precipitation Intensity to Flow Rate Conversion Precipitation Intensity, PI (mm/hr.) 1 2 5 10 20 40 70 130

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Flow Rate, FR (L/min) 0.4 0.7 2 4 7 15 25 50

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CP-CBU-125 B1.2

Sizing the First Flush

This report will take the initial turbidity in rural areas of Cambodia to be 200 NTU, based on data from Uganda. The Project Team recommends a Target Turbidity at Tank Entry of 20 NTU for the Jumbo Jar and 50 NTU for the Concrete Ring Tank and Institutional Ferro-cement Tanks. Water in the large Institutional Ferro-cement Tanks has plenty of time and space for debris to settle on the base of the tank and as such 50 NTU will be sufficient. The Concrete Ring Tanks are around 1500L each, so a standard system is connected in series. This acts as a large first flush system, so 50 NTU will be sufficient. The Jumbo Jar is a single volume with a smaller base area; hence the entry NTU level is more critical to the final water quality. Using Table B1.2.2 and the parameters from Table B1.2.3, the depths to be flushed have been calculated. The Jumbo Jar requires 5.5mm of rainfall be flushed. On a 25m2 roof this equates to . The Concrete Ring Tank requires 2mm of rainfall to be flushed. On a 25m 2 roof this equates to . The Institutional System requires 2mm of rainfall to be flushed. On a 100m 2 roof this equates to .

Table B1.2.2: Calculating the amount of rainfall to initially flush from the system [26]. Initial run-off Turbidity (NTU) 50 100 200 500 1,000 2,000

Target Turbidity at Tank Entry (NTU) 50 20 10 5 0 1.5 2.5 3.5 1 2.5 3.5 4.5 2 3.5 4.5 5.5 3.5 4.5 5.5 6.5 4.5 5.5 6.5 7.5 5.5 6.5 7.5 8.5

Table B1.2.3: System parameters for first flush sizing. Parameters Initial Turbidity (NTU) Turbidity at Entry to Tank (NTU) Roof Area (m2)

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Jumbo Jar 1000 20 25

Concrete Ring Tank 1000 50 25

Institutional System 1000 50 100

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CP-CBU-125 B1.3

Setting the Reset Time

Equation B1.2.1 is developed in [33] and can be used to calculated the optimum reset time for a typical first flush system. (B1.3.1) where tr = Reset time (days) ƞr = Contaminant Removal Efficiency = ffd = Design Diversion, the maximum amount of rainfall a first flush system is capable of diverting (mm) ra = Accumulated Rainfall (mm)

The contaminant removal efficiency of RWC’s system is not known, so further research would need to be conducted to determine its optimum reset time. However, the optimum reset time is generally several days, much higher than is generally achievable. Martinson, Brett and Thomas (2009) recommend that the best approach is to aim for the highest reset time achievable [33]. RWC did not know what the reset time of their current system was. The Project Team conducted research on site and found that the reset time is approximately ten minutes, clearly less than optimal. The approach in the design phase was to aim for a reset time of at hours, but to aim for the highest achievable.

B2

Existing Alternative First Flush Designs

This section discusses alternative designs considered which did not make the prototyping phase. Those that were ultimately selected are discussed in the body of the report, in section 5.2.

Manual Flush This system requires the user to manually divert the flow by rotating a pipe from the storage tank to the ground. After the initial amount of rainfall, the user is required to rotate the pipe back to the storage tank.

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Figure B2.1: Manual First Flush [26]

Table B2.1: Manual First Flush Advantages and Disadvantages Advantages Simplest Design Only 1 moving part No maintenance required No ‘special’ parts required

Disadvantages Requires operator to be present at the time of rainfall Operator likely to get rained on Reliant on user remembering to divert downpipe away from tank after dry spell Likely to be neglected, in which case either all rain or no rain will be flushed

Constant Volume Identical to the existing system, but with no valve. Once flush chamber is full, further rain flows into tank. Table B2.2: Constant Volume Advantages and Disadvantages Advantages Very simple design Not reliant on operator being present during rain No moving parts

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Disadvantages Requires maintenance to remove sludge build up and prevent drip-hole from blocking Dissolved contaminants may end up in the tank through turbulence, as there is no valve

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CP-CBU-125 Tipping Gutter As illustrated in Figure B2.2, the tipping gutter is initially angled, by its own mass, to cause flow away from the storage tank and into a bucket suspended from a pulley. Once the mass of the diverted water in the bucket is sufficient to overcome the mass of the tipping gutter, water from the downpipe flows into the tank. As with the current system, water drips from the bucket at a slow rate to reset the system for the next rainfall. As the density of water can be known, the volume to be diverted can be altered through the dynamics of the pulley system.

Figure B2.2: Fixed Mass Design [46]

Table B2.3: Fixed Mass Advantages and Disadvantages Advantages As the bucket is open, it is easy to see when the sludge needs to be cleaned out Flushed water is fully separated from further flow into the tank (as opposed to most fixed volume designs) Automatic flush and reset Easy to clean

Disadvantages More moving parts than the existing system Suffers from the same issue as the current system in terms of sludge build up, requiring maintenance

Tipping Gutter Without Reset Same as Tipping Gutter but with no reset valve. Bucket must be emptied after each use.

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CP-CBU-125 Table B2.4: Fixed Mas Without Reset Advantages and Disadvantages Advantages User does not have to be present during rainfall Very simple design No maintenance required

Disadvantages Needs manual reset after a few days without rain

Vortex Filter Vortex filter designs such as the WISY design [69] are not strictly speaking first flush devices, but are often included under this category as they are sometimes considered a replacement for a first flush device, and therefore warrant discussion here. As illustrated in Figure B2.5, incoming rainwater forms a vortex, forcing it through a fine mesh filter to the outlet. Leaves and debris fall to the ground or to stormwater, along with around 10% of the total flow, which is wasted [69]. In reality, vortex filters are not first flush systems, as the initial flow of water is not diverted. Any dissolved contaminants or particles small enough to pass through the mesh will not be diverted. They should be considered elaborate filters, aimed at preventing blockages from large particles, requiring minimal maintenance; they are not intended for potable water [69]. Furthermore, it is recommended that the filter be cleaned at least twice a year [69], not an enormous improvement on the three times a year required with RWC’s current system. It is the view of the Project Team that vortex filters should not be viewed as a replacement for a first flush system.

Figure B2.5: Vortex Filter Design [69]

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CP-CBU-125 Table B2.5: Vortex Filter Advantages and Disadvantages Advantages Blocks less easily than standard filters No moving parts

B3

Disadvantages Does not eliminate dissolved particles in initial flow Requires a similar level of maintenance to RWC’s existing system

New Concept Designs for the First Flush System

This section discusses new concepts that were considered but did not make the prototyping phase. Those that were ultimately selected are discussed in the body of the report, in section 5.2. An initial prototype of the Waterwheel Design, included in this section, was constructed, but extensive testing was not conducted.

Waterwheel This design fits into the second category listed under ‘Design Process’, removing the need for maintenance. Instead of storing the flushed water, it runs directly onto the ground, eliminating the risk of blockage even by large matter (for example leaves). Rather than by filling a fixed volume, the amount of diverted water is measured using a water wheel, as illustrated in Figure 5.3.4. Initially, the tipping gutter (lever) is tilted to divert rainwater away from the storage tank as it flows out of the downpipe and over the wheel. As rainwater flows out of the downpipe, the wheel rotates, winding the rope around a spool and gradually tilting the tipping gutter. Eventually, the tipping gutter will be tilted such that any further rain flows into the tank. When the gutter hits the stop, the wheel will no longer be able to rotate. When the rain stops, the mass will gradually pull the tipping gutter back to its initial position, ‘unwinding’ the wheel in the process. The picture in Figure 5.3.4 is large to illustrate the point, but was scaled back during prototyping to a more realistic size.

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Figure 5.3.4: Waterwheel design

Table 5.3.2: Waterwheel design, advantages and disadvantages Advantages Maintenance free- no sludge build up. Fully automated- no user input required at any stage. Initial flow is directly diverted, rather than stored, eliminating need for drip-hole.

Disadvantages Less direct and more complicated way of controlling volume to be diverted than fixed volume/mass designs. Complicated design relative to alternatives, more moving parts than RWC’s current design. Not inherently a closed design – would require an additional housing to fully enclose as desired by RWC.

Counterweight Design This design fits into the first category, largely keeping the existing system in place, but automating the maintenance process. Water from the drip-hole will drain into a bucket, which, when it accumulates sufficient mass, will overcome the mass of the counterweight, opening the cap at the bottom of the flush chamber. All water in the chamber will rush out, removing any sludge with it, in in the process emptying the bucket, closing the cap and reset the system.

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Figure B3.1: Counterweight Design

Table B3.1: Counterweight Design, Advantages and Disadvantages Advantages Automated maintenance procedure Fully automated- no user input required at any stage

Disadvantages Relatively Complex Design The system can be reset while it is still raining, causing clean water to be flushed Difficulty in maintaining seal at the cap More moving parts than current design

Tipping Triangle Design []

B4

Evaluation of Concept Designs and Existing Alternatives

After the qualitative evaluation in the previous section was complete, designs for prototyping were selected based on a formal, quantitative method, using the criteria established in Section 5.1 of the main body. Because some of the Criteria are linked and do not lend themselves to a simple numerical scale, new factors were created to cover each criterion, and designated an appropriate weighting. The Table from Section 5 is shown below (Table B5.1), and linked with the factors for the new framework in Table B4.2. Reliability covers being able to deal with monsoonal flow rates (Criterion 1.) and not becoming a source of additional contamination if left uncleaned (Criterion 4.). Frequency of CP-CBU-125

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CP-CBU-125 Maintenance and Complexity of Maintenance combined cover less maintenance than RWC’s current system, and not blocking easily (Criteria 2. and 3.). Efficiency covers the amount of water lost by diversion being small (Criterion 4.). Manufacturability and Cost cover cheap and easy to produce in bulk (Criterion 7.). User Input covers the ability to function without user input (Criterion 8.). Aesthetic was added with a low weighting due to concern in the community with systems not being unattractive to look at. Factors, weighting, and corresponding criteria are shown in Table B4.1. Weighting was assigned on a scale of 1 -4. Each factor was evaluated for each design on a scale of 1-5, where 5 is excellent and 1 is poor.

Table B4.1: First Flush Criteria First Flush Criteria 1. Be capable of dealing with the high flow rates associated with high rainfall intensities in monsoonal Cambodia. 2. Require less maintenance than RWC’s current system (3 times a year) or no maintenance at all. 3. Will not block easily (if at all) and blockages should be easy to see. 4. Will not become a source of additional contamination if left uncleaned 5. The amount of water lost by diversion or for washing the filter should be only a small part of the total flow. 6. Will be made from locally available materials. 7. Will be cheap and easy to produce in bulk. 8. Will function without user input.

Table B4.2: Establishing a Framework for Evaluation Factor Manufacturability Cost Reliability User Input Frequency of Maintenance Complexity of Maintenance Aesthetic Efficiency (Wastage)

Corresponding Criteria 6,7 7 1,4 8 2,3 2 5

Weighting 2 3 3 4 3 4 1 2

User Input (how often a user is required to operate the system, excluding maintenance) and Complexity of Maintenance were defined as the most important and assigned weightings of CP-CBU-125

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CP-CBU-125 four accordingly. This is because a first flush system becomes pointless if excessive user input is required to the point that a householder must be home during rainfall, and because if maintenance is too complex it is unlikely to be carried out, and is difficult to teach to the layperson. Cost, Reliability, and Frequency of Maintenance were rated next most important with a weighting of three. This is because of the importance of cost for the system to be affordable to rural Cambodians, the fact that reducing the need for maintenance was the main brief of this part of the project, and the obvious need for the system to function reliably in the Cambodian environment to avoid contamination. Manufacturability and efficiency were assigned a value of two. Efficiency (not wasting a large proportion of water) is important, but was not an area highlighted in the project brief. Manufacturability is crucial, but it was felt that this factor was partly covered by cost so it was not assigned too high a value to avoid placing too much emphasis on it. Aesthetics was assigned a value of one as it is not important to the functioning of the system, but householders have expressed a desire for an attractive system. This grading system was used to decide which designs would reach the prototyping phase. Table B4.12 shows the evaluation for all designs, which are justified in Tables B4.3-11. For the new designs, and some existing designs that had not been well documented, it was difficult to assign values with confidence. The grading system was used again after prototyping to determine which systems had been the most successful.

Fixed Volume Ball Valve Table B4.3: Fixed Volume Ball Valve Evaluation Factor

Assigned Value Manufacturability 4 Reliability 4 Cost 4 User Input 5 Frequency of 3 Maintenance Complexity of 3 Maintenance Aesthetic 4 Efficiency 3

CP-CBU-125

Rationale Easy to Manufacture, all parts readily available Very Reliable, only moving part is ball in valve Cheap, no difficult to obtain parts No user input required Maintenance recommended three times a year, room for improvement Requires screw-driver to remove cap Fits neatly against wall, no ‘make-shift’ looking parts Fairly wasteful (See Appendix B12)

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CP-CBU-125 Tipping Gutter

Table B4.4: Tipping Gutter Evaluation Factor Assigned Rationale Value Manufacturability 3 Reasonably easy to manufacture from readily available materials, however some moving parts are required. Reliability 3 Fairly simple and reliable, however additional moving parts could cause intermittent failure. Cost 4 No expensive parts. User Input 5 No user input required. Frequency of 3 Likely to require same amount of maintenance as existing Maintenance system (three times per year), room for improvement. Complexity of 4.5 Very simple to maintain- simply rinse out open bucket. Maintenance Not perfect as it may not be at a convenient height. Aesthetic 3 Not as neat as the existing system. Efficiency 3 Likely to be as efficient as the current system. Counterweight Table B4.5: Counterweight Evaluation Factor

Assigned Rationale Value Manufacturability 1 Difficult to manufacture, parts likely to be difficult to obtain. Many moving parts. Reliability 1 Likely to be unreliable due to complexity and large number of moving parts. Seal is also likely to be difficult to achieve. Cost 1 Likely to be expensive due to difficult to obtain and complex parts. User Input 5 Requires no user input. Frequency of 5 Theoretically requires no maintenance. Maintenance Complexity of 3 Maintenance is likely to be relatively simple if required, Maintenance possibly more complex than it is currently due to more moving parts. Aesthetic 3 Likely to be less attractive than current system as there may be clunky moving parts protruding from neat first flush chamber. Efficiency 3 Efficiency is unchanged from current system.

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CP-CBU-125 Changing Angle

Table B4.6: Changing Angle Evaluation Factor Assigned Rationale Value Manufacturability 4 Easily manufactured from materials already available at RWC. Reliability 4 Only one moving part (the ball in the ball valve). Cost 3 Slightly more expensive than existing system due to a few additional parts User Input 5 No user input required Frequency of 4 It is hoped that necessity for maintenance will be Maintenance reduced. Complexity of 3 Complexity of maintenance is unchanged from existing Maintenance system (screw-driver is required). Aesthetic 3.5 Possibly slightly less attractive than existing system due to eccentric angle and additional support required. Efficiency 4 Hoped to be more efficient than current design. Manual Reset Table B4.7: Manual Reset Evaluation Factor

Assigned Rationale Value Manufacturability 4 Easily assembled from readily available parts. Reliability 5 Extremely reliable – only moving part is ball in ball valve, no hole to block. Cost 3.5 Slightly more expensive than existing design because of tap. However, end cap is no longer required. User Input 2 Requires user input after each rainfall or at least on a weekly basis. Frequency of 5 No maintenance should ever be required as all debris Maintenance should be flushed when tap is opened. Complexity of 3 Tap will need to be removed for maintenance to be Maintenance carried out. Aesthetic 4 Equally as attractive as existing design (fits neatly against wall) Efficiency 5 No water wasted.

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CP-CBU-125 First Flush Ball Valve Table B4.8: First Flush Ball Valve Evaluation Factor

Assigned Rationale Value Manufacturability 3 Moving parts, spring in particular may be difficult to obtain Reliability 4 Although it has moving parts, they are relatively simple, so it should be reliable. Cost 3 More expensive due to the spring, additional parts etc. User Input 5 Requires no user input. Frequency of 5 Should require no maintenance if it performs correctly. Maintenance Complexity of 3 If required, hopefully maintenance will involve simply Maintenance removing the screw-cap and rinsing the ball in water. Aesthetic 5 Even more compact than existing design, everything is internal, sits neatly against wall. Efficiency 3 Will most likely waste the same amount of water as current system due to drainage-hole (estimated 7% of annual rainfall). Tipping Triangle Table B4.8: Tipping Triangle Evaluation Factor

Assigned Rationale Value Manufacturability 2 Moving parts, likely to be difficult to get balance right. Reliability 2 Moving parts, complex, likely to be unreliable under certain flow conditions. Uncertain how it will cope with monsoonal flow rates. Cost 2 Likely to be expensive due to moving parts. User Input 5 Requires no user input. Frequency of 3 Likely to require the same amount of maintenance as Maintenance existing system (utilises similar sized drainage hole). Complexity of 2 Maintenance is likely to be more difficult (will have to Maintenance somehow open up hollow triangle). Aesthetic 3 Likely to be somewhat more ‘clunky’ than current design due to moving parts. Efficiency 3 Will most likely waste the same amount of water as current system due to drainage-hole (estimated 7% of annual rainfall).

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CP-CBU-125 Manual Flush Table B4.9: Manual Flush Evaluation Factor

Assigned Rationale Value Manufacturability 5 Very easy to manufacture - consists of just a moveable downpipe. Reliability 5 Very reliable - no moving parts or complex features to go wrong. Cost 5 Very cheap – consists just of a moveable downpipe. User Input 1 Requires user input every time it rains. Frequency of 5 Will never require maintenance, as flushed water is not Maintenance stored. Complexity of 2 If maintenance is required it will probably mean changing Maintenance the downpipe, which could be complicated. Aesthetic 3 Not as attractive as current system as a long arm will need to swing out from wall. Less compact. Efficiency 5 No water is wasted IF it is used correctly. If used incorrectly, ALL water may be wasted.

Canvas Bag Table B4.10: Canvas Bag Evaluation Factor Manufacturability

Reliability Cost

User Input Frequency of Maintenance Complexity of Maintenance Aesthetic Efficiency

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Assigned Value

Rationale

4 Majority of system is unchanged from existing system, which is easily assembled from readily available parts. Canvas bag is easily attached. If a suitable material cannot be found or fastening mechanism is not available this value may change. 5 Very reliable. Ball from ball valve is only moving part, no drainage-hole. 3 Slightly more expensive than existing system as canvas must be purchased and sewn into bag. It is hoped that material will be sourced second hand. 5 No user input required. 4.5 Maintenance schedule is hoped to be reduced significantly from existing system. 3 Maintenance, when required, will involve unclamping bag and rinsing it out. Screwdriver is required. 2 Not as attractive as current system as bag is hanging off the bottom, will look dirty over time. 4 More efficient than current system, very slow flow-rate weeping through bag.

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CP-CBU-125 Waterwheel Table B4.11: Waterwheel Evaluation Factor

Assigned Rationale Value Manufacturability 1.5 Difficult to manufacture, many moving parts and a waterwheel required. Reliability 4 Should work well under monsoonal flow rates. Cost 2 Likely to be expensive due to numerous unusual/moving parts. User Input 5 No user input required. Frequency of 5 Theoretically no maintenance required. Maintenance Complexity of 4.5 If required, maintenance should be trivial (rinsing with Maintenance water). Aesthetic 2 More obtrusive than existing design. May look more attractive if it can be wholly confined within its casing. Efficiency 5 No water wasted unnecessarily.

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Table B4.12: Evaluation of Designs Factor Weight Fixed Volume Ball Valve Tipping Gutter Counterweight Changing Angle Manual Reset First Flush Ball Valve Tipping Triangle Manual Flush Canvas Bag Waterwheel

Chlorine Filter

Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std.

Manufactu Reliability Cost User Frequency of Complexity of Aesthetic Efficiency Tot. Rank rability Input Maintenance Maintenance (wastage) 2 3 3 4 3 4 1 2 4 4 4 5 3 3 4 3 8 12 12 20 9 12 4 6 83 6 3 3 3 5 3 4.5 3 3 6 9 9 20 9 18 3 6 80 7 1 1 1 5 5 3 3 3 2 3 3 20 15 12 3 6 64 10 4 4 3 5 4 3 3.5 4 8 12 9 20 12 12 3.5 8 84.5 3 4 5 3.5 2 5 3 4 5 8 15 10.5 8 15 12 4 10 82.5 8 3 4 3 5 5 3 5 3 6 12 9 20 15 12 5 6 85 2 2 2 2 5 3 2 3 3 4 6 6 20 9 8 3 6 62 11 5 5 5 1 5 2 3 5 10 15 15 4 15 8 3 10 80 8 4 5 3 5 4.5 3 2 4 8 15 9 20 13.5 12 2 8 87.5 1 1.5 4 2 5 5 4 2 5 3 12 6 20 15 16 2 10 84 4 3.5 4 3.5 5 4 3 4 3 7 12 10.5 20 12 12 4 6 83.5 5

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Better than existing?

N/A No No Yes No Yes No No Yes Yes Yes

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CP-CBU-125 Table B4.13: Post-Prototyping Ranking Rank 1 2 3 4 4 6 6 8 9 10 11

B5

System Canvas Bag Manual Reset Chlorine Filter Changing Angle Fixed Volume Ball Valve Tipping Gutter Manual Flush Waterwheel First Flush Ball Valve Counterweight Tipping Triangle

Prototyping and Optimisation: First Flush Ball Valve Design

Two First Flush Ball Valve prototypes were constructed. Appendix B5.1 describes the test procedures used to evaluate both prototypes. Appendix B5.2 discusses the construction, testing, and evaluation of the first prototype. Appendix B5.3 discusses the construction, testing and evaluation of the second prototype. Appendix B5 has been organised in this fashion to flow with the design process, as the second prototype was created to address issues uncovered with the first prototype during testing.

B5.1

Test Procedures

The following test procedures were used to evaluate and assist with the design of the First Flush Ball Valve prototypes.

Test 1: Setting height of ball above seat (for a given ball-spring sub-system) Objective To determine the distance the ball moves (for a given ball-spring sub-system) from when it is full of water to empty, to assist in determining the height above the seat at which the ball should be suspended in the first flush chamber. Apparatus Ruler, pencil bridging the gap between two chairs, camera (see Figure B5.1.1).

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Figure B5.1.1: Test 1.1 Apparatus

Procedure Fill valve ball with water, hang from pencil (in front of ruler) blocking the drip hole with thumb until ready, then film ball as it drains.

Test 2: Determining quantity of water diverted prior to valve close Objective To determine the quantity of water flushed over a range of reasonable flow rates. Apparatus 30L fermenter propped up on bricks and blocks of wood; mock gutter constructed from PVC T-junction, pipe and cap, with the upper portion sliced off for visibility, propped between two bricks; two 9L plastic buckets; stopwatch. See Figure B5.1.2.

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Figure B5.1.2: Test 1.2 Apparatus

Procedure Fill fermenter to the 30L mark, and fill bucket 1 to 9L. Place bucket 2 underneath the first flush device, to catch the ‘diverted’ water. Open the tap, topping up the fermenter constantly to the 30L mark with bucket 1, to maintain a constant head, time and record how long bucket 1 takes to fill to 9L. When bucket 1 is empty and bucket 2 is full, swap buckets. A third bucket may be required in the cycle to maintain continuity. Record the number of buckets that are filled with diverted water before the valve closes. Once the valve is closed, turn off the tap. Repeat the experiment at different flow rates by partially closing the tap, aiming for flow rates of 1,2,5,10 and 20mm/hr. The tap may need to be removed altogether to achieve the higher flow rates (4L/min was recorded in preliminary testing with the tap fully open), in which case the flow rate should be controlled by varying the head in the fermenter (i.e. filling to 5L, 10L, 20L etc.).

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CP-CBU-125 Test 3: Reset Time Objective To determine the reset time of the system. Apparatus NA Procedure Close valve, fill chamber with water, record time taken both for chamber to empty, and ball to fully drain (may be the same time).

B5.2

First Prototype

Construction The chamber was constructed from a 40cm length of 90mm PVC pipe. Two holes were drilled (on opposite sides of the pipe) 30cm from its base, through which a threaded rod (cut to a length of 110mm) was pushed, held in place by four nuts (two inside and two outside the chamber), with the rubber washers used between the inner nuts and the inside of the pipe to keep the chamber water-tight. A Ping-Pong ball, with six 4mm diameter holes drilled through its top and a pin-hole pushed through its bottom, was suspended from a 150mm length of elastic band attached to the threaded rod by a paper clip, for ease of removal and modification. The bottom of the pipe was closed by a push-on cap, through which a 38mm hole was drilled with a hole saw, around which a cistern ring of the equivalent size was cemented to form a seal with the Ping-Pong ball in the ‘valve closed’ position. Figure B5.1.1 shows unit, and the Figure B5.1.2 shows the cistern valve that serves as the seat for the ball. Figure B5.1.3 and Figure B5.1.4 shows the unit in operation. The height from which the ball was suspended was chosen based on the results of Test 1, discussed below, such that it was empty the valve was open, and when it was full the valve was firmly closed.

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Figure B5.2.1: First Flush Chamber (Provided by the Capstone group)

Figure B5.2.2: First Flush Bottom Cap (Provided by the Capstone group)

Figure B5.2.3: First flush valve open (Provided by the Capstone group) CP-CBU-125

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Figure B5.2.4: First flush valve open/closed (Provided by the Capstone group)

Cost The entire unit came to an estimated total cost of $10.28 (materials only, see Table B5.2.1). This is a very rough estimate of the materials cost, as materials would need to be sourced in Cambodia, and the economics of scale would come into play, but seemed worth mentioning given the $135-160 quoted by SafeRain [31] for a similar unit. Labour costs would also need to be considered, but the system was very simple to construct.

Table B5.2.1: Cost Estimate Item 90mm PVC stormwater pipe (1m) Storm PVC cap 90mm push on Elastic band Rod Threaded 5/16x24 (40cm) Nut 5/16 Rubber washer 5/16 Cistern sealing ring Paper clip PVC cement Total:

CP-CBU-125

Quantity 0.5 1 2 0.25 4 2 1 1 -

Cost per item ($) 5.79 1.20 4.95 0.50 3.94 6.22

Total Cost ($) 2.90 1.20 1.24 1.00 3.94 $10.28

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CP-CBU-125 Test 1 Results See appendix B5.1 for details of the test procedure. The ball/elastic band assembly used in the first prototype moved through 3.8cm from full to empty, and the ball took 24 minutes to drain.

Figure B5.2.5: Test 1 Results

Test 2 Results See Appendix B5.1 for details of the test procedure.

Table B5.2.2: Test 2 Results Test Time to Drain 1L (seconds) Volume Diverted (L) 1 15 5 2 15 3 3 50 DNC* 4 18 1.2 5 27 1.3 6 32 14 7 25 30 8 45 DNC* *DNC = Did Not Close

Table B5.2.3: Results with Analysis (sorted by flow rate) CP-CBU-125

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CP-CBU-125 Time to Fill 1L Test (seconds) 3 50 8 45 6 32 5 27 7 25 4 18 1 15 2 15 *DNC = Did Not Close **Assuming 22m2 ERA

Volume Diverted (L) DNC* DNC* 14 1.3 30 1.2 5 3

Flow Rate (L/min) 1.20 1.33 1.88 2.22 2.40 3.33 4.00 4.00

Precipitation Rate** (mm/hr) 2.88 3.20 4.50 5.33 5.76 8.00 9.60 9.60

Volume Diverted vs Precipitation Rate Volume Diverted (L)

35 30 25

20 15 10 5 0 0.00

2.00

4.00 6.00 8.00 Precipitation Rate (mm/hr)

10.00

12.00

Figure B5.2.6: Volume Diverted vs. Precipitation Rate (Did Not Close below 4mm/hr.)

Discussion As illustrated in Figure B5.2.6, for precipitation rates below approximately 4mm/hr, the valve never closed, as the water flowed down the side of the chamber, never reaching the ball. At higher flow rates (close to 10L/min), the ball filled almost instantly, but generally became caught in the corner of the chamber, outside the cistern ring, until the random flow of water forced it into its seat, resulting in an unpredictable volume of water being diverted. In both runs at this flow rate around 1L was diverted, but it is conceivable that with a larger sample size very little water would be diverted if the ball happened to fall immediately into its seat. At intermediate flow rates (around 2-3L/min) the volume diverted was extremely unpredictable (ranging from 1.2-30L). In this case two mechanisms were at play: firstly, the time taken for the ball to varied vastly depending on where it happened to be hanging and the CP-CBU-125

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CP-CBU-125 random flow of the water, and secondly the ball was at times caught outside the cistern ring, as discussed previously. At this stage the exact volume of water diverted is not the major issue, as it can be altered relatively easily by changing the size of the holes, the main concern is lack of consistency. In addition to the water diverted, an additional 2.5L of water are inevitably wasted, as once the valve is closed the chamber must be filled before any water reaches the tank. This water cannot be considered diverted, as it is free to mix with water flowing to the tank.

Conclusion and Recommendation Clearly, this prototype is not viable given a significant proportion of rain falls at below 5mm/hr [61], in which case no water would ever reach the tank. However, it demonstrates that in principle such a system could be feasible. Table B5.2.4 highlights the issues with the first prototype, and proposes measures to mitigate these issues in the second prototype.

Table B5.2.4: Issues and Modifications Issue with prototype 1a Measure(s) to mitigate in prototype 1b Ball does not always land in seat when  Bigger ball  Bigger hole full- it can become stuck outside sealing  Bigger sealing ring ring, preventing valve from closing. Cap pops off when pipe is full, but  Screw-on cap cementing the cap shut would make access to the ball difficult. Ball fills too quickly under certain  Smaller holes drilled into ball  Experiment with multiple balls circumstances (not enough water with different sized holes flushed). The way water falls through the pipe is  Larger ball relative to pipe diameter unpredictable- in some cases it misses the  ‘Diffusor rings’ to make flow ball altogether (valve never closes), in more predictable other cases it lands directly on ball. Stiffness of elastic bands is unpredictable  Replace elastic bands with spring/nylon thread and difficult to replicate. Pin hole appears to close over time,  Larger pin hole meaning the system does not reset

B5.3

Second Prototype

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CP-CBU-125 Construction Essentially the same construction as the first prototype (see Appendix B5.1 for details), implementing the changes recommended in table B5.2.4.

Changes from the first prototype:         

More compact Screw cap for easier access Larger ball (6cm diameter ‘Splash ‘n’ Play’ Gameballs, see figure B5.3.2) Larger hole in cap and cistern ring Cap is designed to hold cistern ring without needing to cement it on, allowing for it to be replaced if required (see figure B5.3.3) Multiple elastic bands replaced by 20cm length of nylon thread ‘Diffuser ring’ implemented in an attempt to force water to flow over ball at all flow rates (see figure B5.3.4) Larger holes into ball, including larger drainage hole which was drilled with a small drill bit rather than pushed through with a drawing pin (See figure B5.3.2) Fly screen mesh attached over holes to prevent debris from entering ball (See figure B5.3.5)

The fly screen mesh was implemented to prevent particles that could block the drip hole from entering the ball. It was attached to the ball via the elegant mechanism illustrated in Figures B5.3.5 and B5.3.6. A second ball was cut into slightly larger than a half, and a cross cut into it corresponding to the location of the holes in the main ball. A cross-shaped portion of mesh was placed over the holes on the main ball, and the second pushed over the top, holding the mesh in place.

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Figure B5.3.1: Second Prototype

B5.3.2: Ball Valve

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B5.3.3: Cap with Ball Seat and Sealing Ring

Figure B5.3.4: Diffusor Ring

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B5.3.5: Ball with Fly Screen Mesh

Figure B5.3.6: Fly Screen Mesh Fastening Mechanism

Figure B5.3.7: Clogged Fly Screen Mesh

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CP-CBU-125 Test 2 Results Table B5.3.1: Prototype 2, Test 2 Data

Volume Diverted (L)

Time to Drain 1L Test # (secs) 1 17 2 370 3 32 4 40 5 16 6 6

Volume Diverted (L) 2 2 16 6 1 1

Flow rate (L/min) 3.53 0.16 1.88 1.50 3.75 10.00

Precipitation rate* (mm/hr) 8.47 0.39 4.50 3.60 9.00 24.00

Volume Diverted vs. Precipitation Rate, Second Prototype

18 16 14 12 10 8 6 4 2 0 0.00

5.00

10.00

15.00

20.00

25.00

30.00

Precipitation Rate (mm/hr)

Figure B5.3.8: Volume Diverted vs. Precipitation Rate, Prototype 2

Discussion The second prototype appeared to be generally more consistent than the first, as hoped, although there was still one major anomaly of 16L diverted at a flow rate of approximately 2L/s. The main improvement was the fact that it was effective even at low flow rates. It was found to be effective over the entire range of estimated operating conditions. Unfortunately, after only a few days outside both the mesh and drip-hole in the ball became blocked, photographed in Figure B5.3.7. It was observed that when wet, the elastic material used as the spring expanded and became slack, as the still hollow ball rested on its seat. This did not affect the operation of the system, as the ball bobbed up and down allowing water to pass through until it had accumulated sufficient mass not to float, thus closing the valve. This observation gave rise to the idea that the spring could be dispensed with, an idea which was explored with a third prototype, discussed in Appendix B5.4.

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CP-CBU-125 Conclusion and Recommendations The volume diverted is still somewhat unpredictable, as illustrated in Figure B5.3.8, particularly at lower flow rates. Further testing would be required to see whether large deviations (see Test #3, Figure B5.3.8) from the average are anomalies or standard. The Project Team believes that issues with consistency could be overcome with further minor modifications and additions along the lines of the diffusor ring. However, the more serious issue of the blocked mesh and drip-hole appear to be inherent to the system. Prototyping confirmed that this was a problem, as predicted in the design stage. While prototyping, an independent review of two commercial First Flush Valves was found, from a household owner who had used the SafeRain system and an American system. The owner reported that both systems had been problematic, with the valve either never closing (presumably clogged mesh) or never opening (presumably clogged exit hole), adding further evidence to the contention that the system was problematic. The Project Team believes that there is no benefit to this system. It is a complicated, less direct design, which is harder to maintain or repair, and does not solve RWC’s maintenance problem. The second prototype was left with RWC to connect to their test system if they are interested, but it was not recommended that the design be pursued further.

B5.4

Third Prototype

This prototype is a modified version of the first prototype. The spring was replaced with a solid shaft, shown in Figure B5.4.2. The ball was modified to have a hole in the top to fit over the shaft, shown in Figure B5.4.3. The ball is able to slide up and down the shaft. When the ball is hollow, its buoyancy causes it to float as water begins to fill the chamber, allowing the initial flow to be flushed. When the ball is full, it does not float and closes the valve. As such, its function is unchanged by replacing the spring with a shaft. Replacing the spring is advantageous as they are expensive and were difficult to come by even in Australia.

Figure B5.4.1: Prototype 3

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Figure B5.4.2: Spring Replacement

Figure B.4.3: Modified Ball

B6

Prototyping and Optimisation: Canvas Bag Design

B6.1

Material Testing

Materials Three materials were selected for testing: 1. Denim 2. Artists’ Canvas 3. Canvas from a canvas water-bag

Procedure Each material was tested using the quick release fastening mechanism illustrated in Figure B6.1.1, constructed from a length of 90mm PVC downpipe over which a thin strip of 90mm PVC downpipe was cemented, with an extra piece of pipe cemented to fill the resultant gap, photographed in Figure B6.1. CP-CBU-125

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Figure B6.1.1: Downpipe End Fitting for Canvas Bag Attachment

A circle of roughly 30cm diameter was cut from each fabric, and fastened (one at a time) to the downpipe using a screw clamp, photographed in Figures B6.1.2, B6.1.3, and B6.1.4. This design of ‘bag’ was initially favoured due to its simplicity and ease of manufacture. The pipe was then filled to with water to a head of 25cm and observed.

Figure B6.1.2: Denim Material Testing

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Figure B6.1.3 Artists’ Canvas Material Testing

Figure B6.1.4: Canvas Water-Bag Material Testing

Results and Discussion Both artists’ canvas and denim were much too porous, with the entire pipe draining in under a minute in both cases. The canvas waterbag also drained too quickly, however in this case the vast majority of the water was escaping through the join between fabric and pipe. This is CP-CBU-125

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CP-CBU-125 because the material was thick and stiff, and water escaped between the folds visible in Figure B6.1.4. The porosity of the canvas water-bag appeared to be more suitable, and worthy of further investigation.

B6.2

Fastening Mechanism

Quick Release Fastening Mechanism The quick release fastening method, illustrated in Figure B6.2.1 and discussed in the test procedure of materials testing (Appendix B6.1), proved effective with both the artists’ canvas and denim. However, when a circle of canvas water-bag material was fitted by this method, the material was too stiff and thick, with water escaping between the folds visible in Figure B6.4. To address this issue, a bag was custom made to fit snugly over the downpipe. The design was very simple- a rectangle of fabric was cut, sewn into a cylinder, and the end sewn shut. Simplicity was chosen over aesthetic. This design proved much more effective, and is photographed in Figure B6.2.2.

Figure B6.2.1: Quick Release Fastening Mechanism

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Figure B6.2.2: Custom Canvas Water-Bag Testing

The quick release fastening mechanism with custom bag was tested by filling the downpipe to a pressure head of 40cm, and measuring the change in pressure head with time. Time, and distance from the top of the pipe to the water level were measured. As the distance from the pipe to the bottom of the bag was 42cm, the pressure head was calculated using the following equation:

(B6.2.1) Where PH = Pressure Head (cm) and d = distance from top of pipe to water level (cm). The time derivative of pressure head was taken to obtain flow rate in cm/min:

(B6.2.2) Where FR = Flow Rate (cm/min), PH = Pressure Head (cm) and t = time (mins). The flow rate was converted to L/min by multiplying by the cross-sectional area of the pipe (roughly the same as the cross-sectional area of the bag) and dividing by 1000:

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(B6.2.3) (B6.2.4) Where A = Area (cm2), D = Diameter (cm), FRvolumetric = Flow Rate (L/min), and FR = Flow Rate (cm/min). Table B6.2.1 shows the results. Figure B6.2.3 plots pressure head against time, Figure B6.2.4 plots flow rate against time, and Figure B6.2.5 plots flow rate against pressure head.

Table B6.2.1: Test Data Time (mins) 0 2 4 6 8 10 15 20 30 40 50 60 75 90 120 150 180 240

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Distance from top (cm) 1.5 4 5.5 8 10 11.5 14.5 17 20.5 22.5 24 25.5 27 28 30 31 33.5 34

Pressure Head (cm) 40.5 38 36.5 34 32 30.5 27.5 25 21.5 19.5 18 16.5 15 14 12 11 8.5 8

Flow Rate (cm/min) 1.25 0.75 1.25 1.00 0.75 0.60 0.50 0.35 0.20 0.15 0.15 0.10 0.07 0.07 0.03 0.08 0.01 -

Flow Rate (L/min) 0.080 0.048 0.080 0.064 0.048 0.038 0.032 0.022 0.013 0.010 0.010 0.006 0.004 0.004 0.002 0.005 0.001 -

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Pressure Head vs. Time 45 Pressure Head (cm)

40 35 30 25 20 15 10 5

0 0

50

100

150

200

250

300

Time (seconds)

Figure B6.2.3: Pressure Head vs. Time

Flow Rate vs. Time 0.09

Flow Rate (L/min)

0.08 0.07

0.06 0.05 0.04 0.03 0.02 0.01 0 0

50

100

150

200

Time (s)

Figure B6.2.4: Flow Rate vs. Time

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Flow Rate (L/min)

Flow Rate vs. Pressure Head 0.090 0.080 0.070 0.060 0.050 0.040 0.030 0.020 0.010 0.000 0

5

10

15

20

25

30

35

40

45

Pressure Head (cm)

Figure B6.2.5: Flow Rate vs. Pressure Head

While the flow rates recorded the quick release fastening mechanism/custom bag combination were reasonable, the trend in Figure B6.2.5 suggests that they may become an issue at higher pressure heads, which will be experienced in operation as the downpipe will be much longer. However, this mechanism, using canvas water-bag material, was deemed worthy of in-field investigation to see how it functioned at higher pressure-heads.

Alternative Fastening Mechanism The alternative fastening mechanism illustrated in Figure B6.2.6 was also built. Due to the stiff nature of the canvas, the design had to be modified. Rather than having a bag protruding through the hole at the bottom of the cap, a 90mm diameter circle of canvas was cut out and fastened flat over the hole in the cap. Given the success of the quick-release fastening measure, the alternative fastening mechanism was not pursued further.

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Figure B6.2.6: Alternative Fastening Mechanism

B6.3

In Field System Testing

Implementation After the initial discussion of our work to date with RWC upon arrival, it was agreed that the canvas bag design was a promising avenue and that it should be tested with RWC’s existing system. It was implemented on RWC’s test system by replacing the cap with a reducer connected to a short length of RD90mm pipe. The canvas bag was forced over the pipe, and fastened with the screw clamp, shown in Figure B6.3.1.

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Figure B6.3.1: In-Field Implementation

Testing The system was filled by running water over the roof to simulate rainfall (see Figure B6.3.2). Even with the high pressure head relative to testing conducted in Appendix B6.2, leakage from the join was minimal. Furthermore, the fastening mechanism was adequate without the lip shown in Figure B6.1.1, making the system even simpler. The reset time of the system was approximately 8hours, a significant improvement of the current reset time of 10minutes. The wastage flow-rate was not measured, but was visibly significantly lower than for the current system. Water was dripping from the canvas bag rather than gushing out in a constant stream as with the drainage-hole in the current system.

Materials The only two materials required in addition to what is already used is a suitable replacement for the canvas waterbag material, and a screw-clamp capable of fastening it to a DN90mm pipe. Unfortunately neither could be sourced during the group’s market visits. However, CP-CBU-125

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CP-CBU-125 RWC staff expressed confidence that a suitable material for the bag could be found locally by people who knew where to look. Smaller diameter screw-camps were found locally, suggesting that larger clamps may be available as well. RWC staff knew of a local who would be able to sew the canvas bags.

B7

Prototyping and Optimisation: Waterwheel Design

A working model was constructed to demonstrate the principle of this design, but a full-scale system ready to be implemented on site was not constructed due to time constraints.

Figure B7.1: Waterwheel Concept Prototype

Construction: Gutter: 90mm PVC pipe, cut in half and to a length of 20cm, with a hole drilled through one end to connect. Waterwheel: Taken from an old children’s bath toy. Shaft: Piece of something from a hardware store, cut to a length of 15cm, with a small hole drilled through it to fasten the rope. Interference fit with waterwheel. Rope: Length of sewing thread, attached to shaft and gutter, looped over the frame as a pulley. Gutter ‘hinge’ mechanism: Piece of wire bent around the gutter, with a hook bent on either side. Attached to the gutter by two nuts, bolts and washers. Hooks were hung over the same shaft as the waterwheel. Frame: Constructed from k’nex

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CP-CBU-125 Results and Discussion The system was a success in that it demonstrated that the principle is sound. When water was poured over the wheel (simulating water from a downpipe), roughly one litre was ‘diverted’ before the gutter was tilted the other way (in practice towards the tank). It was hoped that the gutter would have sufficient mass that when water was not running it would ‘reset’ by unwinding the string, spinning the waterwheel in the opposite direction. In practice, there was too much friction between the shaft and gutter ‘hinge’, and the system did not fully reset. This problem could be solved either by adding additional mass to the gutter, or by reducing friction. The downside to adding mass to the gutter is that it would make it more difficult for flowing water to lift the gutter. Friction could be most easily reduced by suspending the gutter separately to the waterwheel shaft, as most of the friction on the shaft is from the weight of the gutter.

Conclusion and Recommendations The Project Team believes that by minimising friction and balancing the mass to be as great as possible while still allowing the wheel to spin from the weight of water the system could be viable. However, it is a complicated system with moving parts, and as parts rust and wear friction between components will increase, meaning that the system will not reset. These issues make it unlikely to be suited to rural Cambodia. The design’s two main advantages are that it theoretically never requires maintenance or any other user input, and that it does not waste water during rain (as opposed to systems with a drainage hole which is constantly wasting a small amount of water during rainfall). The system was presented to RWC for them to investigate further if desired, but was not pursued further by the Project Team.

B8

Prototyping and Optimisation: Angled First Flush

B8.1

Preliminary Testing

Objective To determine the wastage flow rate of RWC’s existing system over a range of angles, and to determine the maximum angle at which the ball valve functions.

Procedure A spare first flush chamber already constructed at RWC’s office was used for this experiment. The chamber was positioned against the wall at a range of angles from 0 -75°, in intervals of 15°. Each angle was accurately achieved by measuring the appropriate horizontal distance from the wall to the bottom of the chamber and the vertical distance from the ground to the top of the chamber. These distances are shown in Table B8.1.1. CP-CBU-125

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CP-CBU-125 Table B8.1.1: Distances to Determine Angle Angle (degrees) 0 15 30 45 60 75

Vertical Distance (m) 1.07 1.03 0.93 0.76 0.54 0.28

Horizontal Distance (m) 0.00 0.28 0.54 0.76 0.93 1.03

The chamber was then filled with water using a hose, and maintained full by leaving the tap running. The time taken to fill a 1.5L water bottle from the drainage hole was measured, and used to calculate the wastage flow rate.

Results and Discussion The results are shown in Table B8.1.2. As the hole-size was difficult to measure, as it is so small, the theoretical results were plotted using a range of hole-sizes until the best fit for the data was found. This was found for a hole-size of 2.39mm and is plotted in Figure B8.1.1. Appendix B11 provides more detail on the theory and calculations behind the flow-rate calculations. It was observed that the maximum angle at which the ball valve closed properly was 60°. Figure B8.1.2 plots the theoretical percentage saving for each angle compared to vertical, along with the measured data points.

Table B8.1.2: Wastage Flow Rate Results Angle (degrees) 0 15 30 45 60 75

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Time to Drain 1.5L (s) 69 69 79 86 116 161

Wastage Flow Rate (L/min) 1.30 1.30 1.14 1.05 0.78 0.56

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Figure B8.1.1: Wastage Flow-Rate vs. Angle

Chart B8.1.2: Percentage Saving

The discrepancies between the theoretical and measured values of wastage flow rate, highlighted in Figure B8.1.1, can probably be explained by measurement errors. Unfortunately, due to time constraints in Cambodia, the test was only carried out once. In any case, the fit is reasonably good. The effectiveness of the system is limited by the ball valve. Theoretically, the maximum possible saving is 30%, as the chamber cannot be angled beyond 60°. The recorded saving at 60° is 40%. CP-CBU-125

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CP-CBU-125 B8.2

Prototype

Construction A prototype was constructed using materials already available at RWC’s office, by simply modifying the existing system. The T-junction to a downpipe was left unchanged. A rightangle joint was attached directly below the T-junction, facing directly away from the wall. The first flush chamber was attached to this joint via a second right-angle joint, allowing it to be rotated in the plane of the wall by twisting the second right-angle joint. For a schematic diagram see the body of the report, Figure 5.3.5. The T-junction was fastened to a tree via a plank of timber, two brackets, and some nails. The bottom of the chamber was supported by a stepladder, allowing the angle to be changed while providing adequate support for 10kg of water when full. The system is photographed in Figure B8.2.1.

Figure B8.2.1: Angled First Flush Prototype

Discussion The prototype was tested in a similar fashion to that described for the preliminary testing. The prototype was a success in that the flow rate visibly slowed at higher angles. The usefulness of the concept depends on the assumption that a larger hole will be less likely to block than a smaller hole. Intuitively, this assumption seems reasonable. Furthermore, when the prototype was tested with the addition of a handful of dirt, the hole became blocked long before the build up of debris in the chamber was sufficient to cover the drainage-hole, proving that at least in some cases the hole becomes blocked by dissolved particulate matter rather than by sludge build up. This implies that a smaller hole may block more easily (as matter that would pass through a larger hole could block a smaller hole). If the assumption is correct, the system could be used in one of three ways: CP-CBU-125

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CP-CBU-125 1. Keep the hole-diameter the same, decreasing the wastage-flow rate without affecting the likelihood of blockage. 2. Increase the hole-diameter to keep the wastage flow rate the same, decreasing the likelihood of blockage without affecting the wastage flow-rate. 3. Increasing the hole-diameter somewhat, decreasing both the wastage flow-rate and likelihood of blockage to a lesser extent.

B8.3

Conclusion and Recommendations

The prototype is capable of successfully producing a wastage flow-rate reduction of up to 30% with no modification to hole-size. Alternatively, the hole-size could be increased while keeping the flow rate the same, or a compromise between the two objectives. Before implementing this system, further testing would need to be conducted to confirm the hypothesis that a larger hole is less likely to block than a smaller one. If this is not the case, flow rate can be reduced much more easily by simply reducing hole-size.

B9

Prototyping and Optimisation: Chain Filter

Materials       

Thick chain Thin chain Metal bar Bolts Plastic bottle Bucket Pipe

Procedure The thin chain was secured to the pipe outlet and the other end of the chain lead to the opening of the bucket. Initially the chain was kept in tension and straight from top to bottom to test if the water would follow the chain. Water was then poured at different flow rates to test if the chain could direct large and small volumes of water. The chain was then put at different angles and different tensions with the same tests repeated at each position. At the completion of these tests, the thin chain was replaced by a thick chain and the tests were repeated. Results and Discussion

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CP-CBU-125 Table B9.1: Small Chain Results

Straight in Tension Straight with slack Slight angle in tension Slight angle with slack Large angle in tension Large angle with slack

Small Chain Low Flow Medium Flow No Loss No Loss No Loss No Loss Small Loss Small Loss Small Loss Medium Loss Medium Loss Large Loss Large Loss Large Loss

High Flow Small Loss Small Loss Medium Loss Large Loss Large Loss Large Loss

Table B9.2: Large Chain Results

Straight in Tension Straight with slack Slight angle in tension Slight angle with slack Large angle in tension Large angle with slack

Large Chain Low Flow Medium Flow No Loss No Loss No Loss No Loss No Loss No Loss No Loss Small Loss Small Loss Medium Loss Medium Loss Large Loss

High Flow No Loss No Loss Small Loss Medium Loss Large Loss Large Loss

Conclusion and Recommendations Any water which made initial contact with the chain seemed to follow the chain regardless of the chains arrangement. The chain hung from the middle of the outlet of the pipe, therefore the water exiting the perimeter of the pipe would never make contact with the chain. As the angle increased, the volume of water making contact with the chain decreased, resulting in a large loss of water. The thicker chain minimised this slightly, however not completely. It is recommended that a basketball ring setup is used, as shown in Figure B9.2. This will maximise the amount of water initially incident on the chains. This should be trialled more extensively before it is put into the field.

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Figure B9.2: Basketball Chain Design

B10

Prototyping and Optimisation: Chlorine Filter

Figure B10.1: ‘Chlorine Filter’ Prototype

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CP-CBU-125 Construction A simple prototype for testing was constructed using a standard end-cap, a 15cm length of 30mm pipe, and a bottle cap. A 2.5mm drainage-hole was drilled through the bottom of the end-cap. Numerous holes of a smaller diameter pipe were drilled through the length of pipe, leaving the lower 4cm untouched. The pipe was glued over the drainage hole, and the bottle cap glued over the pipe, using PVC glue. The prototype is depicted in Figure B10.1.

Objective The tests aimed to provide an initial insight into whether or not the concept would be effective at dealing with sludge, i.e. not block as easily as the existing system.

Procedure The end-cap prototype was attached to the bottom of an existing system, with the original drainage hole blocked. The chamber was filled with water, as well as a handful of dirt.

Results and Discussion With the same amount of dirt added which blocked the existing system while testing it at various angles (see Appendix B8.2), the new prototype did not block. Unfortunately, the join between pipe and cap failed when the cap was removed from the first flush chamber, and due to time constraints more testing was not able to be conducted.

Conclusion and Recommendations This test suggests that the concept could be effective. The project team believes it to be worthy of further examination. Clearly, the structural integrity of the system would need to be improved for it to be viable. Figure B10.2 shows a potential new way of attaching the pipe to the end-cap more reliably. A larger hole is drilled through the end-cap (presumably with a hole-saw) such that the small pipe can be pushed through it as an interference fit. The small pipe is then capped at both ends, and the drainage-hole drilled through the bottom cap. The pipe is then glued to the cap. In this case, the interference fit will provide most of the structural integrity, with the glue serving only to prevent it from slipping and seal the join.

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Figure B10.2: Alternative Fastening Mechanism

B11

Theoretical Calculations: Angled First Flush

Figure B11.1: Geometry

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CP-CBU-125 Bernoulli’s Equation states that:

(B11.1) Conservation of mass for an incompressible fluid:

(B11.2) Substituting into Bernoulli’s Equation:

(B 11.3) Treating the top surface above the first flush system as point one and the stream of water exiting the drainage hole as point 2, the pressure at each point is equal. Therefore:

(B11.4)

In our case, the pressure head was modified by varying the angle of the first flush system, as illustrated in Figure. The following relationship holds:

(B11.5) The values measured from RWC’s existing system, drawn in Figure B11.1, were substituted, yielding the theoretical flow rate/angle relationship plotted in Figure B11.2.

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Figure B11.2: Theoretical Wastage Flow Rate

The theoretical percentage saving produced by the system was calculated by comparing the wastage flow-rate at each angle with the wastage flow-rate at vertical: (B11.6) The theoretical saving is shown in Figure B11.2. The code used to generate these figures is given in Appendix B16.1.

Figure B11.3: Theoretical Percentage Saving CP-CBU-125

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CP-CBU-125 Reset time, used in the creation of the design charts given in Appendix B15, was calculated as follows: Reset time (t reset) is the time taken for the pressure head in the first flush chamber (h) to fall from its maximum level (h max) to zero. Assuming that the drainage-hole area is much smaller than the area of the entrance to the first flush chamber, flow rate through the system can be expressed as: (B11.7) Assuming the cross-sectional area of the first flush chamber is constant, the flow rate through the system corresponds in the change in pressure head (water level) with respect to time, multiplied by the area of the first flush chamber. (B11.8) Equating equations B11. and B11., (B11.9) Solving yields equation B11. for reset time. (B11.10)

(B11.11)

(B11.12)

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CP-CBU-125 B12

Existing System Testing: Reset Time & Wastage Flow-Rate

Objective RWC had not conducted formal testing into the reset time of their existing first flush system. Wastage flow-rate (defined previously as the flow rate through the drainage-hole when the first flush chamber is full, corresponding to the rate of water wastage during a rain event) was not a factor that had been considered by RWC previously. It was observed in field that the wastage existing system’s flow-rate was much higher than had been expected by the Project Team. This test aimed to quantify the both reset time and wastage flow-rate of RWC’s existing system, to compare with alternative designs.

Procedure Testing was conducted on the first flush system in place on the test RWH system at RWC’s office. To determine the reset time, the first flush chamber was filled with tap water, and the time taken for the system to drain to the level of the drainage hole was recorded. To determine the wastage flow rate, water was run through the system from the roof, simulating rainfall. The time taken to fill a 1.5L bottle from the drainage-hole was recorded, and used to calculate wastage flow-rate. Figure B12.1 illustrates the process.

Figure B12.1: Testing Wastage Flow-Rate CP-CBU-125

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CP-CBU-125 Results & Discussion Test results are shown in Table B12.1. The average reset-time was ten and a half minutes, much shorter than the optimal reset time discussed in Appendix B1.3 (a period of days), however it is recognised that the optimal reset time is generally unobtainable. Rearranging equation B1.1.2, the average wastage flow-rate corresponds to a precipitation intensity of 3.8mm/hour on RWC’s RWH system. It is difficult to know how significant this is without data specific to Phnom Penh. However, to give some idea, the rainfall data from monsoonal India [61] that was used to estimate operational flow rates shows that at different times of year, in various locations in India, between ten and sixty percent of total rainfall fell at intensities lower than 4mm/hour. None of this rainfall would reach the tank with RWC’s current system, and some proportion would be wasted even at higher precipitation intensities. This suggests that there are significant benefits to be gained by reducing the wastage flowrate.

Table B12.1: Existing System Test Results

Test 1 Test 2 Test 3 AVERAGE

Reset Time Time to Flush first Wastage Flow(mins:secs) 1.5L (seconds) Rate (L/min) 10:18 57.50 1.57 10:50 55.00 1.64 10:09 60.00 1.50 10:26 57.50 1.57

Conclusion The high wastage flow-rate and short reset-time suggest that there are significant benefits to be gained by increasing reset-time and reducing wastage flow-rate in RWC’s current system.

B13

Post-Prototyping/Cambodia Trip Evaluation

After prototyping the new designs and travelling to Cambodia, the formal evaluation carried out to shortlist designs for prototyping (Discussed in Appendix B4) was repeated with a better understanding of both the designs and the context. This evaluation was assisted with the Project Team’s recommendations to RWC. The results are given in Table B13.6. The rationales behind any changes from the pre-prototyping evaluation are given in Tables B13.16. Any designs not mentioned were unchanged from the pre-prototyping evaluation.

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Table B13.1: Changes, Fixed Volume Ball Valve Factor Efficiency

Old Value 3

New Value 2.5

Rationale The wastage flow-rate was higher than anticipated, along with a much faster reset time.

Table B13.2: Changes, Angled First Flush Factor Efficiency

Old Value 4

Frequency of 4 Maintenance

New Value 3.5

3.5

Rationale The system could not be angled as far as expected, meaning the flow rate was not reduced as much as expected. The system could not be angled as far as expected, meaning the hole size could not be increased as much as expected, probably leading to more frequent blockages.

Table B13.3: Changes, First Flush Ball Valve Factor Reliability

Old Value 4

Frequency of 5 Maintenance

New Value 2

2.5

Rationale The volume of water flushed was found to be highly unpredictable, and to vary over a range of flow rates, even with modifications to mitigate this. The system was found not to be maintenance free as hoped, but to apparently block even more easily than RWC’s existing system.

Table B13.4: Changes, Canvas Bag Factor Efficiency

Old Value 4

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New Value 4.5

Rationale The wastage flow rate was found to be even slower than expected, and the reset time longer, largely because of the success of the fastening mechanism

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Table B13.5: Changes, Waterwheel Factor Manufacturability

Old Value New Value 1.5 1

Reliability

4

1

Rationale Producing the prototype was more difficult than expected Factors such as humidity may affect the friction, which will have a major impact on the volume flushed. Flow-rate could also affect the volume flushed.

Table B13.6: Changes, Manual Flush Factor Frequency of Maintenance

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Old Value New Value 5 4.5

Rationale Theoretically, the system should never require maintenance, hence the perfect score for this factor. However, one of the manual flush systems at an institution was blocked when the Project Group visited. It is unknown whether this is an isolated incident- RWC staff had never encountered the problem before. Nonetheless, the frequency of maintenance score was lowered to reflect some uncertainty.

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Table B13.6: Post-Prototyping Evaluation Factor Weight Fixed Volume Ball Valve Tipping Gutter Counterweight Changing Angle Manual Reset First Flush Ball Valve Tipping Triangle Manual Flush Canvas Bag Waterwheel

Chlorine Filter

Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std. Val. Std.

Manufactu Reliability Cost User Frequency of Complexity of Aesthetic Efficiency Tot. Rank -rability Input Maintenance Maintenance (wastage) 2 3 3 4 3 4 1 2 4 4 4 5 3 3 4 2.5 8 12 12 20 9 12 4 5 3 82 3 3 3 5 3 4.5 3 3 6 9 9 20 9 18 3 6 80 5 1 1 1 5 5 3 3 3 2 3 3 20 15 12 3 6 64 9 4 4 3 5 3.5 3 3.5 3.5 8 12 9 20 10.5 12 3.5 7 3 82 4 5 3.5 2 4.5 3 4 5 8 15 10.5 8 13.5 12 4 10 81 2 3 2 3 5 2.5 3 5 3 6 6 9 20 7.5 12 5 6 71.5 8 2 2 2 5 3 2 3 3 4 6 6 20 9 8 3 6 62 10 5 5 5 1 5 2 3 5 10 15 15 4 15 8 3 10 80 5 4 5 3 5 4.5 3 2 4.5 8 15 9 20 13.5 12 2 9 88.5 1 1 1 2 5 5 4 2 5 2 3 6 20 15 16 2 10 74 7 3.5 4 3.5 5 4 3 4 2.5 7 12 10.5 20 12 12 4 5 82.5 5

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Better than existing?

No No Same No No No No Yes No Yes

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CP-CBU-125 B14 Cost Savings Analysis for Modifications to Existing System (Angled First Flush and Canvas Bag Designs) The financial savings created by these designs were calculated by assigning a monetary value to water, and determining the quantity of water saved by each design. The cost of water for villages in Cambodia was determined with a cost analysis using an existing formula. The interviews conducted, along with discussions with professionals at RWC, provided the team with information about the locals’ water habits. The relevant information used in our CAPEX is summarised in Table B14.2. The next step was to use rainwater data, as seen in Table B14.1, to calculate the hours per year that it rains and the amount of water ‘wasted’ by the first flush system emptying at the end of each rain event. This is shown in Table B14.3. The other source of wasted water is that which is continuously streaming out of the bottom of the first flush while it is raining, which is governed by the flow rate when full. Therefore, the total volume of water wasted each year by the first flush is the sum of water wasted while raining and water flushed at the end of a rain event. Using the value of water calculated in Table B14.2, the total annual value of water wasted was calculated, shown in Table B14.4. This table compares the existing system with the innovative angled system and bag prototype. It is shown that the advancement of angling the first flush can save 50% in the cost of wasted water, while the bag prototype can save over 90%. The porous bag has the lowest wastage flow-rate and highest reset time, while maintaining the volume of water flushed.

Table B14.1: Monthly Rainfall Events in Phnom Penh, Cambodia Month January February March April May June July August September October November December Total

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Rain Events 2.8 2.4 5.2 8.6 16.4 16.6 19.6 21.4 19.8 24 11.8 4.8 153.4

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CP-CBU-125 Table B14.2: Cost of Water to Average Villager in Cambodia Quantity Hours Distance to water $USD/Hour Wage of unskilled labourer $USD/Hour Value used for villager Litres Water collected $USD/Litre Cost of water Total cost for average family $ USD

Units/day Units/year 2 730 $ 0.63 $ 0.63 $ 0.31 $ 0.31 200 73000 $ 0.003 $ 0.003 $ 0.63 $ 228.13

Table B14.3: Annual Rainfall Amount of rain (days/year) Average time per rainy day (Hours/day) Time per year it rains (Hours/year) Rain events in a rainy day (#/day) Rain events in a year (#/year) Flush after rain event (L) Total Flushed after rain events (L/year)

Appendix B15

153.4 1.5 230.1 2 308 10 3080

First Flush Drainage-Hole Size and Angle Design Charts

The following charts were created to assist RWC in designing their first flush system. Figures B15.1-4 can be used either to determine the wastage flow-rate for a known angle and drainage-hole diameter, or to determine possible configurations for a desired wastage flowrate. Similarly, Figures B15.5-8 can be used either to determine the reset-time for a known angle and drainage-hole diameter or to determine possible configurations for a desired resettime. The drainage-hole in RWC’s current system is roughly 3mm in diameter. The figures below are useful across a range of diameters from below 1mm up to 6mm. Figure B15.1 shows the entire range, while Figures B15.2-8 are broken into subsections to improve readability. The same theory described in Appendix B11 underpins these charts. The MATLAB code used to create the charts is given in Appendix B16.2.

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Figure B15.1: Wastage Flow-Rate, 0-6mm

Figure B15.2: Wastage Flow-Rate, 0-1.5mm

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Figure B115.3: Wastage Flow-Rate, 1.5-3mm

Figure B15.4: Wastage Flow-Rate, 3-6mm

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Figure B15.5: Reset Time, 0-0.5mm

Figure B15.6: Reset Time, 0.5-1m CP-CBU-125

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Figure B15.7: Reset Time, 1-2mm

Figure B15.8: Reset Time, 2-6mm CP-CBU-125

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CP-CBU-125 Appendix B16 AB16.1

First Flush MATLAB Code

Existing System Theory vs. Test Comparison

The following script was used in Appendices B8 and B11. %========================================================================= %This script plots the theoretical flow rate and percentage saving at each %angle tested for RWC's existing system, then superimposes the data points %from field tests for comparison purposes. %=========================================================================

g=9.81; D_1=0.09; D_2=0.00239;

%gravity, m/s %Diameter of ENTRANCE pipe to FF (not FF pipe) %Drainage hole diameter

A_1=pi*D_1^2/4; %Area of ENTRANCE pipe to FF A_2=pi*D_2^2/4; %Area of drainage-hole theta=0:0.01:90; %range of angles theoretically possible h=1.07*cosd(theta); %pressure head accross range const=A_2*sqrt(2*g/(1-(A_2/A_1)^2)); %constant used in following eqn Q_wastage=const*sqrt(h)*60*1000; %theoretical wastage flow rate across range percentage_saving=(Q_wastage(1)-Q_wastage)/Q_wastage(1)*100; %theoretical percentage saving accross possible range of angles test_angle=[0,15,30,45,60,75]; %angles tested test_flowrate=[1.30,1.30,1.13,1.04,0.78,0.56]; at each angle tested

%wastage flow-rate observed

test_percentage_saving=(test_flowrate(1)test_flowrate)/test_flowrate(1)*100; %observed percentage savings at each angle figure(1) %plots theoretical wastage flow-rate plot(theta,Q_wastage); title('Wastage Flow Rate vs. Angle'); xlabel('Angle From Vertical (Degrees)'); ylabel('Wastage Flow Rate (L/min)'); hold on %superimposes test results over theoretical wastage flow-rate plot(test_angle,test_flowrate,'rx') hold off figure(2) %plots theoretical percentage saving at each possible angle plot(theta,percentage_saving) grid on

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CP-CBU-125 hold on %superimposes observed percentage saving at each angle tested plot(test_angle,test_percentage_saving,'rx'); title('Percentage Saving vs. Angle') xlabel('theta (degrees)') ylabel('Saving (%)') hold off

B16.2 RWC Design Charts The following script was used in Appendix B15. %========================================================================== %The following sizing charts can be used to determine the wastage flow-rate %of RWC's existing system for a given angle and hole size, or to determine %possible configurations for a desired flow-rate. %========================================================================== g=9.81; D_1=0.09; L=1.18;

%gravity, m/s %Diameter of ENTRANCE pipe to FF (not FF pipe) %length of FF chamber

A_1=pi*D_1^2/4; %Area of ENTRANCE pipe to FF %Steps through a range of angles, plotting wastage flow-rate against %drainage-hole diameter for each one for theta=[0,43,57,68,76,82,87,89,90] %range of angles %For most even distribution of lines: %theta=[0,42.7,57.3,67.9,76.1,82.2,86.6,89.1,90] h=L*cosd(theta); %pressure-head D_2=0:0.00001:0.006; %range of drainage-hole diameters A_2=pi.*D_2.^2./4; %range of drainage-hole areas const=A_2.*(2*g./(1-(A_2./A_1).^2)).^(1/2); %used in following eqn Q_wastage=const.*sqrt(h)*1000*60; %range of wastage flow rates t=(A_1./A_2).*sqrt(2/g).*h.^(1/2)./60; %reset time in minutes %wastage graphs-------------------------------------------------------figure(1) plot(D_2*1000,Q_wastage) %plots wastage-flow rate agains D_2 hold on title('Wastage Flow-Rate vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Wastage Flow-Rate (L/min)'); grid on text(6.02,0.1,'\theta=90\circ') text(6.02,1.1,'\theta=89\circ') text(6.02,2,'\theta=87\circ') text(6.02,3.1,'\theta=82\circ') text(6.02,4,'\theta=76\circ') text(6.02,5,'\theta=68\circ')

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CP-CBU-125 text(6.02,6,'\theta=57\circ') text(6.02,7,'\theta=43\circ') text(6.02,8.15,'\theta=0\circ') %Close up wastage graph for 0-1.5mm range figure(2) plot(D_2*1000,Q_wastage) axis([0 1.5 0 0.6]) hold on title('Wastage Flow-Rate vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Wastage Flow-Rate (L/min)'); grid on text(1.51,0.02,'\theta=90\circ') text(1.51,0.07,'\theta=89\circ') text(1.51,0.12,'\theta=87\circ') text(1.51,0.19,'\theta=82\circ') text(1.51,0.25,'\theta=76\circ') text(1.51,0.315,'\theta=68\circ') text(1.51,0.38,'\theta=57\circ') text(1.51,0.45,'\theta=43\circ') text(1.51,0.52,'\theta=0\circ') %Close up graph for 1.5-3mm range figure(3) plot(D_2*1000,Q_wastage) axis([1.5 3 0 2.2]) hold on title('Wastage Flow-Rate vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Wastage Flow-Rate (L/min)'); grid on text(3.02,0.02,'\theta=90\circ') text(3.02,0.25,'\theta=89\circ') text(3.02,0.5,'\theta=87\circ') text(3.02,0.75,'\theta=82\circ') text(3.02,1,'\theta=76\circ') text(3.02,1.25,'\theta=68\circ') text(3.02,1.5,'\theta=57\circ') text(3.02,1.75,'\theta=43\circ') text(3.02,2.1,'\theta=0\circ') %close up graph for 3-6mm range figure(4) plot(D_2*1000,Q_wastage) axis([3 6 0 9]) hold on title('Wastage Flow-Rate vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Wastage Flow-Rate (L/min)'); grid on text(6.02,0.1,'\theta=90\circ') text(6.02,1.1,'\theta=89\circ')

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CP-CBU-125 text(6.02,2,'\theta=87\circ') text(6.02,3.1,'\theta=82\circ') text(6.02,4,'\theta=76\circ') text(6.02,5,'\theta=68\circ') text(6.02,6,'\theta=57\circ') text(6.02,7,'\theta=43\circ') text(6.02,8.15,'\theta=0\circ')

%Reset time plots-----------------------------------------------------figure(5) plot(D_2*1000,t) axis([0 6 0 120]) hold on grid on figure(6) plot(D_2*1000,t/60) axis([0 0.5 0 20]) hold on grid on title('Reset time vs. Drainage-Hole Diameter','Position',[0.25 20.75]); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Reset time (hours)'); text(0.06,20.4,'\theta=0\circ') text(0.105,20.4,'43') text(0.13,20.4,'57') text(0.15,20.4,'68') text(0.17,20.4,'76') text(0.19,20.4,'82') text(0.21,20.4,'87') text(0.235,20.4,'89') figure(7) plot(D_2*1000,t/60) axis([0.5 1 0 4.5]) hold on grid on title('Reset time vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Reset time (hours)'); text(0.54,4,'\theta=89\circ','Color','b') text(0.54,3.3,'\theta=87\circ','Color','b') text(0.54,2.8,'\theta=82\circ','Color','b') text(0.54,2.3,'\theta=76\circ','Color','b') text(0.54,1.9,'\theta=68\circ','Color','b') text(0.54,1.4,'\theta=57\circ','Color','b') text(0.54,0.9,'\theta=43\circ','Color','b') text(0.54,0.53,'\theta=0\circ','Color','b') figure(8) plot(D_2*1000,t) axis([1 2 0 70]) hold on

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CP-CBU-125 grid on title('Reset time vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Reset time (minutes)'); text(1.1,57,'\theta=89\circ','Color','b') text(1.1,47,'\theta=87\circ','Color','b') text(1.1,41,'\theta=82\circ','Color','b') text(1.1,34,'\theta=76\circ','Color','b') text(1.1,27,'\theta=68\circ','Color','b') text(1.1,21,'\theta=57\circ','Color','b') text(1.1,14,'\theta=43\circ','Color','b') text(1.1,9,'\theta=0\circ','Color','b') figure(9) plot(D_2*1000,t) axis([2 6 0 16]) hold on grid on title('Reset time vs. Drainage-Hole Diameter'); xlabel('Drainage-Hole Diameter (mm)'); ylabel('Reset time (minutes)'); text(2.25,12,'\theta=89\circ','Color','b') text(2.25,10.3,'\theta=87\circ','Color','b') text(2.25,8.8,'\theta=82\circ','Color','b') text(2.25,7.4,'\theta=76\circ','Color','b') text(2.25,6,'\theta=68\circ','Color','b') text(2.25,4.5,'\theta=57\circ','Color','b') text(2.25,3.3,'\theta=43\circ','Color','b') text(2.25,1.9,'\theta=0\circ','Color','b') end figure(1) hold off figure(2) hold off figure(3) hold off figure(4) hold off figure(5) hold off figure(6) hold off figure(7) hold off figure(8) hold off figure(9) hold off figure(10) hold off

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Table B14.4: CAPEX: Evaluation of the Cost of Wasted Water from the Existing System Compared to Proposed Systems Existing System Angle (Degrees)

Angled System

Bag Prototype

Height difference (m)

0 0

0 0

15 0.16

30 0.31

45 0.44

60 18.31

75 18.16

0 0

Test 1 (Hr) Test 2 (Hr) Test 3 (Hr) Flow Rate While Raining(L/Hr) Hourly Waste of Water Whilst Raining ($USD/Hr) Flush per Hour of Rain(L/year) Yearly Waste of Water Whilst Raining ($USD/year) Total Flush Water Emptied Per Year (L/year) Total Wasted Emptying Flush Water Per Year ($USD/year) Total Wasted Emptying Flush Water Per Year ($USD/year)

0.015 0.0153 0.0153 98.36 $0.307 22633 $70.73 3080 $9.63 $9.63

0.019

0.019

0.022

0.024

0.032

0.045

1

78.26 $0.245 18008 $56.27 3080 $9.63 $9.63

78.26 $0.245 18008 $56.27 3080 $9.63 $9.63

68.35 $0.214 15728 $49.15 3080 $9.63 $9.63

62.79 $0.196 14448 $45.15 3080 $9.63 $9.63

46.55 $0.145 10712 $33.47 3080 $9.63 $9.63

33.54 $0.105 7718 $24.12 3080 $9.63 $9.63

1.50 $0.005 345.15 $1.08 1534 $4.79 $4.79

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Appendix C - Tank Systems C1 Existing Alternative Tank Designs This section provides an outline of the alternative tank designs available to Rainwater Cambodia that are currently in use around the world. The two domestic tank systems already in use by RWC are also included for comparison. Jumbo Jar (Thai Jar) The Jumbo Jar is one of two domestic tanks designs currently in use by RWC [2]. It is a high quality tank with roof, similar in many ways to the traditional ‘Thai Jars’ that became widespread across Thailand in the 1980’s. The Jumbo jar is considered a high cost, high quality tank in comparison to other low cost rainwater harvesting designs and tanks have a lifespan well over 20 years. The Jumbo Jar is constructed from ferro-cement, is built on site by local tradespeople and is produced from locally purchased materials.

Figure C1.1: Jumbo Jar built by RWC technicians [2].

CP-CBU-125 Concrete Ring Tank The second of the two domestic tank designs currently in use by RWC. The Concrete Ring tank is a build from premade concrete cylinders, joined together with bar reinforcing mesh and mortar. The tanks can be built to a standard 1500L size or alternatively can be increased in size by adding more concrete rings. The Concrete Ring tanks are considered very reliable, with a predicted lifetime of 20 years. The construction of the tank is completed by trained local tradespeople, with some labour by the household, often as payment-in-kind.

Figure C1.2: Cement Ring Tank constructed by RWC technicians [2].

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CP-CBU-125 Tarpaulin Tank The tarpaulin tank is a very inexpensive design that originated out of Uganda. The box frame is made from organic or readily acquired materials, such as bamboo or other woods. The frame is then filled in using organic material such as ferns, grasses or whatever is readily available. The frame is then lined with a plastic waterproof tarpaulin which often has to be imported. Ideally the design is then covered, often with galvanised sheeting as a roofing material. The tarpaulin tank is a low cost, low lifespan alternative to the Ferro-cement tanks currently in use by RWC. It is considered here as a replacement for the Ferro-cement tanks, but due to the loss in quality, lifespan and probable increase in maintenance this may not be viable. The tarpaulin tank is however an excellent candidate for an increase in system capacity at a low cost. The tarpaulin tank is a potential solution for the issue of local residents cutting open the piping to Ferro-cement tanks to add grey water.

Figure C1.3: Tarpaulin Tank, original design by ACORD in Uganda [65].

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CP-CBU-125 PVC Cloth Bag Originally developed by International Development Enterprises (iDE) in Bangladesh, this design uses locally available materials such as bamboo to construct the tank frame. In a similar manner to the tarpaulin tank, a PVC liner is then fitted inside a cloth bag, which is then placed into the tank frame. The version included here from [70] uses 2 lined bags, and additional plumbing and taps so no dipping of carrying vessels into the tank is required. The capacity of this design is 3000L and is estimated to cost around $30 to construct in Bangladesh. This assumes the organic frame materials are locally available free of charge and that households do all their own labour. The PVC Cloth bag design is of particular interest to the Cambodian context due to its low cost and ease of manufacture. The potential lies in the installation of a PVC Cloth Bag tank as the primary water storage, or as an additional storage capacity to an existing system at very low cost. The PVC cloth bag tank, in a similar way to the tarpaulin tank, could be a viable solution to the issue of greywater addition to the Ferro-cement tanks.

Figure C1.4: The Cloth Bag tank design [70].

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CP-CBU-125 Pumpkin Tank The Pumpkin tank design is variation of the Thai Jar Ferro-cement tank. Initially developed as part of the Community Water Supply and Sanitation Programme in Sri Lanka in 1995, the tank is approximately spherical in shape. This allows greater forces to be applied on the tanks walls, leading to a decrease in wall thickness and associated reduction in cost. Due to its spherical top portion the design also removes the need for a lid or roof, further reducing costs. A further improvement in shape on this design is a spherical tank. These tanks are in construction in Cambodia at a local NGO called Resource Development International Cambodia (RDIC). They are located just outside of Phnom Penh, perhaps 40 minutes from RWC’s office.

Figure C1.5: The Pumpkin Tank design [71, 72]

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CP-CBU-125 Interlocking Block Tank This new approach to tank design uses interlocking bricks to build the tanks walls. The bricks are handmade in the same fashion as a regular fired brick but they shape is altered somewhat. The interlocking wall structure spreads the pressure load across adjacent bricks and results in large reductions in the amount of mortar used, and hence a large reduction in cost. The design itself is quite clever and the interlocking concept is perhaps something RWC may look into exploring to reduce material use in their tank design.

Figure C1.6: The interlocking block tank design [73].

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CP-CBU-125 Semi-Submerged Brick Cistern The semi-submerged brick cistern is a dome shaped tank built beneath the surface, with only the topmost point of the dome protruding for access. The walls are constructed from brickwork and minimal amounts of mortar are used for reinforcement. This has the effect of creating a somewhat flexible structure that uses the surrounding earth to support much of the load. The benefit is the decrease in mortar greatly reduces the cost to produce the tank. The disadvantages of this design are; water storage is below ground level and hence a pumping system is required, maintenance access is poor and soil and climate conditions dictate to some degree where this design will be effective.

Figure C1.7: The Semi-submerged Brick Cistern [74].

Premade Thai Jar The factory and workshop produced Thai Jars are mass produced in Thailand using high quality moulds and mortar techniques. This results in a very standardised, high quality product at a low cost. The Premade Thai Jar tanks are available in Cambodia for very low cost. The main downside of the premade option is that the tank is imported. It does not utilise local community members in its construction, which results in a lack of knowledge for repair and maintenance. The transport of the jar to the site is also an issue and an additional cost.

Figure C1.8: Premade Thai Jar design [52, 73, 75-78]. Images taken from [27]. CP-CBU-125

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CP-CBU-125 Closed Frame Ferro-cement Tank The tank is made using flat sections of available, low cost steel as reinforcement. The sheets are curved in sections and then bolted together. The sheeting is then covered in wire mesh and covered with cement. The sheeting is then removed and the inside covered with cement, followed by a waterproof slurry.

Figure C1.9: Construction of the Closed Frame Ferro-cement Tank [74].

Open Frame Ferro-cement Tank Similar in design to the closed frame version, the open frame version sees the mesh and reinforcement framework combined into one. The entire wire-steel frame is then cemented over to create a tank of similar strength to the closed frame version. [27] suggests the design concentrates the wall stresses somewhat and is slightly more expensive than the closed frame version.

Figure C1.10: The Open Frame Ferro-cement Tank [73].

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CP-CBU-125 Plate Tank The semi-submerged plate tank design sits mostly underground and is extremely common in Brazil. Precast plates are held in place with wire mesh, which is then cemented over inside and out to form the tank. The roof is made in a similar fashion but with different precast parts.

Figure C1.11: The Plate Tank [74] Moulded Plastic One of the most common RWH storage tanks in both the developed and developing world, these tanks are mass produced in a variety of shapes and sizes. The moulded plastic tanks are often quite inexpensive to manufacture, although transport costs and difficulties often prohibit access for many communities. The other disadvantage is the loss of business for the community and a lack of knowledge and resources when maintenance issues arise.

Figure C1.12: Moulded Plastic tank in Sri Lanka [76].

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CP-CBU-125 Recycled Container Uses two drums stacked vertically and welded together. An external sand filter helps improve the quality of stored water; however this can cause lots of overflow in heavy rains. These drums are made centrally and transported to site.

FigureC1.13: Recycled Container Experimental Rammed Earth Tank This is an experimental tank built at Kyera Farm, Mbarara, Uganda during June and July 2000. This type of tank is still at the experimental stage and is NOT recommended for manufacture as yet. The tank described below failed after being filled, but was due to a poor lining, which was the result of bad workmanship. A mixture of and cement is rammed and packed into a moulded shape. The shape of the mould is round and the soil-cement mixture is very compact. Levels of rings are built one on top of each other until the desired height is reached. The tank is rendered internally with cement mortar. A thin-shell Ferro-cement cover is then used on top of the finished rendered tank.

Figure C1.14: ‘Section’ of rammed earth tank wall being built to multiple levels [74]

Figure C1.15: The completed tank [74] CP-CBU-125

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CP-CBU-125 Tube Tank The tube tank, tested in Sri Lanka, Uganda and Ethiopia, is a small tank, stripped to the bare essentials. Water storage is in a plastic tube and extraction by a PVC pump. The slab can be precast in a steel mould either on site or in a central location. The tank design is particularly suited to rapid implementation projects such as refugee camps where a quick solution is required for water provision ahead of more permanent measures. If householders do the excavation, an agency can simply transport a number of prefabricated parts and each tank can be assembled within an hour. Tank size is determined by the depth of the hole, so the deeper a household digs, the larger the store. Extra storage is relatively cheap as the cost of the tank is dominated by the concrete slab. The longevity of the tube is variable, but it will normally need replacing every year or so.

Figure C1.16: General Arrangement of Tube Tank

Above Ground Mud tank The mud tank, as tested in Sri Lanka, is an above ground tank with much of the economy of a below ground tank. Wattle and daub is a widespread practice for building from earth, particularly when householders build their own homes. The technique uses unmodified mud to fill a frame structure made from round wood. The materials necessary for this type of constructions are all gatherable, so cash costs are low, being limited to the liner and plumbing.

Figure C1.17: Bamboo Structure of Mud Tank (Left) and the completed tank (Right) CP-CBU-125

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CP-CBU-125 Premade Thai Jar Originally from Thailand in the 1980’s, the Thai Jar takes advantage of an optimised shape making it material efficient. They are mass produced, giving it a good economy of scale which is unusual for medium sized jars. They can be found throughout Southeast Asia. The jars are manufactured using moulds enabling a high level of consistency and reliability.

Figure C1.19: Premade Thai Jar Being Transported to Site [74] Moulded Plastic High-density polyethylene (HDPE) tanks can be found worldwide. They are Made in factories, requiring expensive machinery. Growing in popularity as they compete with concrete tanks on price, however are still expensive in developing countries. They are light to transport and quick to install making them desirable to some NGO’s.

Figure C1.20: Moulded Plastic Tank CP-CBU-125

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CP-CBU-125 Ferro-Cement Plastic Lined Ground storage solution made of cement and iron wire mesh. Typically installed for irrigation, however could be adapted for large storage of RWH. Being built into the ground cuts down on the required cement, while the plastic lining ensures leaking does not occur.

Figure C1.21: Ferro-Cement Lined Tank

Plastic Lined Pond A standard pond built to catch runoff rainwater from hills. The plastic lining improves quality of water, while decreasing seepage. This method is used to supply whole communities with water and could be used in conjunction with domestic RWH as a secondary source of water

Figure C1.22: Plastic Lined Pond

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CP-CBU-125 Header Bag Header bags are plastic bags which are suspended off the ground using a platform or frame. This is a very cheap alternative to cement tanks. The life cycle of a header bag is determined by the local environment. This could be an option for secondary storage to a more permanent tank.

Figure C1.23: Header Bag Earth Mound Bag Similar to a header bag in cost, however has a greater life cycle due to the rugged plastic material. The earth mound bag only requires a natural or manmade elevation of the height of a bucket. A pump or hose is needed to fill bags from the storage tanks, therefore applicable as a secondary tank.

Figure C1.24: Earth Mound Bag

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CP-CBU-125 Partially Below Ground Dome Tank This tank uses the advantages of both above and below ground tanks, with the ability to be scaled up to over 12,000 L. Taking advantage of the external reinforcement from the earth, while being protected against contamination by surface run off. This tank has the capacity to be implemented for institutions due to its large capacity.

Figure C1.25: Partially Below Ground Dome Tank

Single Skin External Reinforced Usually a single-skin brick wall has insufficient hoop strength to endure the pressure head created by the stored water. This tank utilises cheap external reinforcement so a second layer of bricks is unnecessary, effectively reducing the number of bricks by half. Most externally reinforced tanks utilise the properties of the earth by digging a hole. Relying on the earth for external support is not always suitable due to soil properties, water table levels and materials of the tank. The single skin external reinforcement can be used in any environment regardless of these factors. The single skin external reinforced tank is a promising design with the possibility to substitute the Cement Ring tank and Jumbo Jar.

Figure C1.26: Single Skin Externally Reinforced Tank

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CP-CBU-125 C2 Tank Specifications and Design Criteria The tank in RWC’s RWH system must meet a series of Basic Design Requirements (BDR’s) to be a viable solution for the system. These BDR’s were developed with RWC to reflect the needs of their RWH system. Any alternative tank design that does not meet the BDR’s will not be considered in further analysis. Table C2.1: The Basic Design Requirements for potential tank designs. Basic Design Requirement

Criteria

Water loss (seepage, evaporation) Safety Closed to environment Locally Available Materials

Less than 5% loss by volume Risk level less than 89 (low risk)* No light or direct particle entry possible Materials must be available in nearest city The tank operation must be able to be understood, replicated and communicated by RWC to the local inhabitants. The tank must be repairable/replaceable by the locals. Water must comply with Cambodian Drinking Water Standards, shown in Table 3.2.1 Minimum 3 year

Repair and Maintenance by Locals Water Quality Lifespan

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CP-CBU-125 The Optimisation Criteria (OC) is used to compare the alternative tank designs and make recommendations on the best designs for RWC’s situation. The criteria were selected based on discussions with RWC and the EWB Field Engineer James Oakley. The Optimisation Criteria are presented in Table C2.2.

Table C2.2: The Optimisation Criteria for potential tank designs. Optimisation Criteria

Cost

Ease of Construction

Local Skill Development and Training

Transportation to Site

Explanation The cost of the tank construction, including maintenance, transportation and labour. The material lists for each tank were generated through research of existing design and construction manual publications. The costs were quoted from local merchants in Cambodia by the local RWC staff, so as to obtain an accurate bill of materials for construction. Takes into account the construction time simplicity of construction tasks. The degree to which the tank construction will contribute to the upskilling of local residents. RWC trains a number of local entrepreneurs in the community to construct all the tanks for that project. They are then available to repair and maintain the systems once installed. This provides valuable jobs, training, knowledge transfer and income to the local communities which are an important component of RWC’s strategy for the implementation of RWH. The transport complexities of materials and complete/semi-complete components.

Lifespan

The design must be constructed from locally available and cost effective materials. This for both practical reasons and to ensure the money invested in building the system goes to local merchants to support the growth of their community. The amount of maintenance the tank requires and the cost and complexity of repairing the tank The time the tank will remain operation before it deteriorates beyond useful condition.

Simplicity

The degree to which the design is simple in nature and easy for local residents to understand

Local Materials

Maintenance

Capacity

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The storage capacity of the tank and the ability to increase the storage capacity (upscale the design).

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CP-CBU-125 C3 Existing Alternative Tank Designs This section discusses the alternative tank designs investigated from developing countries around the world. Table C3.1 summarises all the tank designs investigated. For further information on individual tank designs see Appendix C1.

Table C3.1: Alternative low cost tank designs from around the world. Tank Design Concrete Ring Tank Jumbo Jar Tarpaulin Tank Cloth Bag Pumpkin Tank Interlocking Block Tank Semi-submerged Dome Tank Premade Thai Jar Closed Frame Ferro-cement Open Frame Ferro-cement Plate Tank Moulded Plastic Single Skin External Reinforced Tank Rammed Earth Tank Tube Tank Above Ground Mud Tank Large Partially Under Ground Dome Tank Ferro-Cement Plastic Lined Plastic Lined Pond Header Bag Earth Mound Bag

CP-CBU-125

Location Cambodia Cambodia Uganda Bangladesh Sri Lanka Thailand Brazil Thailand, various Africa, Asia, Americas Asia, Africa Brazil Worldwide Various Uganda Sri Lanka, Uganda, Ethiopia Sri Lanka Various Various Various Various Various

Source RWC [2] RWC [2] ACORD [65] iDE [70] Rees [79] IDRC [73] Gnadlinger [74] Various, images [26] Gnadlinger [74] IDRC [73] Gnadlinger [74] Various, images [76] DTU [26] DTU [26] DTU [26] DTU [26] DTU [26] iDE [52] iDE [52] iDE [52] iDE [52]

192

CP-CBU-125 C4 Evaluation of Existing Alternatives The alternative tank designs were first measured against the Basic Design Requirements (BDR’s) listed in Table C2.1. Any designs that did not meet these requirements were discounted from further analysis. See Table C4.1 for the results; tanks highlighted grey did not meet one or more BDR. The tanks that did not meet the BDR’s are discussed here. The Plastic Lined Pond and Ferro-Cement design fails due to being open to the environment. Furthermore, the Plastic Lined Pond fails the Water Loss BDR according to [52]. The Rammed Earth design fails the Safety BDR as it failed in practice. It is included here because the concept itself is valuable and [26] contends that the tank failed due to poor workmanship. Further research and testing of this design would need to be completed before it could be included in recommendations to RWC. The Premade Thai Jar, Moulded Plastic tank, Header Bag, Clothe Bag and Earth Mound Bag all fail the Locally Available Materials BDR. These pre-built solutions remove the manufacturing and labour opportunities from the local community, something which RWC works hard to ensure doesn’t happen. This approach to RWH is appropriate and often necessary for some situations, but in the RWC context it is considered an incomplete, unsustainable solution. The Recycled Container design fails the Water Quality BDR, based on the Cambodian drinking water standards. This is primarily because the previous use of the recycled container can be unknown and chemical contaminants may be present. This system is also considered inappropriate for RWC because poor quality local imitations are possible, the failure of which affects the professional reputation RWC has worked hard to build with local communities. The Tube Tank fails the Lifespan BDR as [52] designed the tank as a fast, short term drinking water solution. [52] recommends the liner bag be replaced every year, effectively meaning the tank has a 1 year lifespan.

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Table C4.1: The alternative tank designs evaluated against the Basic Design Requirements shown in Table C2.1.

Tank

Water Loss < 5%

Safety

Closed to environment

Locally Available Materials

Repair and Maintenance by Locals

Water Quality

Lifespan

Concrete Ring Tank Jumbo Jar Tarpaulin Tank Cloth Bag Pumpkin Tank Interlocking Block Tank Semi-submerged Dome Tank Premade Thai Jar Closed Frame Ferro-cement Open Frame Ferro-cement Plate Tank Moulded Plastic Recycled Containers Rammed Earth Tank Large Partially Underground Tank Single Skin External Reinforced Tank Tube Tank Above Ground Mud Tank Ferro-Cement Plastic Lined Plastic Lined Pond Header Bag Earth Mound Bag

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y N Y Y

Y Y Y Y Y Y Y Y Y Y Y Y Y N Y Y Y Y Y Y Y Y

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y N N Y Y

Y Y Y N Y Y Y N Y Y Y N Y Y Y Y Y Y Y Y N N

Y Y Y Y Y Y Y Y Y Y Y N Y Y Y Y Y Y Y Y Y Y

Y Y Y Y Y Y Y Y Y Y Y Y N Y Y Y Y Y Y N Y Y

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y N Y Y Y Y Y

CP-CBU-125 Table C4.2: The alternative tank designs evaluated against the Optimisation Criteria shown in Table C2.2.

Tank Concrete Ring Tank Jumbo Jar Tarpaulin Tank Pumpkin Tank Interlocking Block Tank Semi-Submerged Dome Tank Closed Frame Ferrocement Open Frame Ferrocement Plate Tank Above Ground Mud Tank Large Partially Underground Dome Tank Single Skin External Reinforced Tank

Cost 3 5 9 7 4

Ease of Construction 6 5 7 5 2

Transportation to Site 4 5 6 5 4

Local Skill Development and Training 7 7 5 7 7

6

4

5

7

5

5

6

5

5

5

7

5

5

5

5

5

7

5

3

4

4

7

7

4

6

5

4

6

6

Local Materials 5 5 5 5 5

Simplicity 5 5 7 4 3

Total 49 50 54 51 41

5

4

47

5

5

5

47

5

5

5

5

47

4

5

5

5

4

41

5

5

4

5

4

5

45

6

7

5

6

8

7

4

52

6

7

5

5

6

7

5

53

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Maintenance Capacity Lifespan 6 6 7 6 5 7 5 5 5 6 5 7 6 5 5

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The remaining tanks in Table C4.1 are further analysed against the Optimisation Criteria in Table C2.2. The results of this analysis are shown in Table C4.2 and the rating system used is discussed here. The analysis shows that the Large Partially Underground Dome Tank, Single Skin Externally Reinforced Tank, Pumpkin Tank, Jumbo Jar and Tarpaulin Tank are the most appropriate tank designs for RWC. This is valuable feedback for RWC, to know that the Jumbo Jar is one of the most competitive designs. The Open Frame and Closed Frame Ferro-Cement Tank designs also score well, as they are similar to the Jumbo Jar in design. The Jumbo Jar comes in at a slightly cheaper price due to the shape optimisation of the design. The rounded construction of the Jumbo Jar results in a reduction in surface area for the same volume storage. The reduction in area means less cement is utilised in the tanks construction, resulting in a lower cost and higher overall rating. The same is true for the Pumpkin Tank design. It is similar in all ways to the Jumbo Jar design, but further optimises the shape of the tank. Hence it is slightly cheaper than the Jumbo Jar due to the decrease in the amount of cement used in its construction. The Semi-Submerged Dome Tank scores highly due its reduced cost to size ratio, which is achieved by utilising the earth for structural support. The design uses a flexible, high lime content mortar to allow the brickwork to move as the earth expands and contracts with the change in season. This design is heavily dependent on the soil in the community which the tank is to be installed. Included in the cost of below ground and semi-submerged tanks is a basic rope pump. These pumps are often available for purchase in many developing countries or can be constructed from locally available materials according to the manuals listed in Appendix O. Rope pumps are readily available from local NGO’s in Cambodia for around $7. Both the Tarpaulin Tank and the Semi-Submerged Dome Tank include the cost of a rope pump for analysis purposes. The tanks identified as having potential for RWC and recommendations on their implementation are discussed in Section 6-Tanks and Section 8-Recommendations and Conclusions

CP-CBU-125 C5 Analysis of Issues with Existing Tank C5.1 Summary of Issues The Cement Ring Tank’s and Ferro Cement Tank’s cleaning have the tendency to leak due to high pressure head. The valve is made from PVC, which erodes over time. Once the valve has eroded it is difficult to replace as the tank must be emptied for this to be achieved. Furthermore, the part is difficult to source in village communities. A further issue the Project Team discovered with the existing tanks is that the current overflow arrangement, seen in Figure C5.4.2, releases the best quality water when the tank is full. C5.3 Proposed Solutions The Project Team has used an overflow arrangement shown in Figure C5.4.1. This design has been prototyped and tested. The tests confirmed that when the tank is overflowing, water is sucked from the bottom and expelled out of the top. This achieves the goal of expelling the lowest quality water from the bottom of the tank, as well as continuously cleaning the tank of settled debris. A hose can be attached to the outlet of the overflow pipe to empty the tank for cleaning purposes. The water must be siphoned through the hose; a method familiar with villagers. This decreases the pressure head on the seal to only a few centimetres, solving the leaking issue. There is no need for cleaning valves at the bottom of the tank with this overflow arrangement. C5.4 Prototype and Testing Construction A 200L metal drum was used to prototype the design, depicted in Figure C5.4.3. A hole was drilled close to the top of the tank, shown Figure C5.4.2 in. An ‘S’ shape pipe was constructed from 3 sections of straight pipe and two 90 degree elbow bends. The bottom of the ‘S’ shape pipe sat on the bottom of the tank. The outlet of the piping was pushed through the top hole and was sealed. Objective The first objective was to determine if the overflow arrangement starts to empty water when the level passed the height of the outlet of the pipe, seen in Figure C5.4.4. The second objective was to determine if the suction created on the inlet of the pipe was strong enough to clean the bottom of the tank. The third objective was to be able to empty the tank through a hose attached to the outlet, by creating a siphon.

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CP-CBU-125 Procedure The initial test was to fill the tank a level higher than that of the outlet and observe if the water flowed through the pipe and out of the outlet. It was also noted how low the water level got before the flow stopped. The next test was an extension of the initial test. Berries were placed in the bottom of the tank, to represent settled debris, shown in Figure C5.4.5. The tank was filled to over the level of the outlet and it was observed if the berries were sucked from the bottom of the tank and expelled through the outlet of the pipe. The final test was to try to empty the tank from the outlet of the ‘S’ pipe by creating a siphon. Results and Discussion The overflow arrangement successfully drained water when the tank was filled past the outlet of the overflow pipe. The water stopped draining when the level reached just below the outlet of the overflow pipe. All berries were sucked out when placed near the inlet of the pipe. When the berries were placed on the opposite end of the tank, it was seen that the suction was not strong enough to suck the berries out. When a hose was attached to the pipe, it was possible to start a siphon to empty the tank completely. Conclusion and Recommendations Although the berries were not sucked out when positioned on the opposing side of the tank, the overflow arrangement prototyped is recommended to be installed in tanks. It is assumed that stronger suction will be created in the full sized system due to bigger pipes and a larger pressure head. It is recommended that the bottom of the tank is sloped towards the inlet of the overflow pipe so that debris naturally settles close to the inlet.

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Overflow Outlet

‘S’ shaped pipe

Overflow Inlet

Figure C5.4.1: Technical Drawing of Prototype

Figure C5.4.2: Hole for the outlet of the overflow pipe CP-CBU-125

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CP-CBU-125 Overflow

Drainage Figure C5.4.3: Constructed Prototype

Figure C5.4.4: Prototype undergoing initial testing Berries sucked from bottom of test tank

Figure C5.4.5: Berries being sucked through the inlet of the overflow pipe CP-CBU-125

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CP-CBU-125 C6 Equations C6.1 Sizing Tanks Equation C6.1.1 shows a how the annual consumption is calculated. Equation C6.1.1 - Q – Annual consumption (Litres) - C – Consumption per capita per day (Litres) - n - Number of people per household The annual consumption is used to determine the storage requirement in Equation C6.1.2. Equation C6.1.2 -

q – Storage requirement (Litres)

-

T - Longest average dry period (days)

The supply approach is used when there are periods of the year where the supply exceeds demand, while other periods result in a deficit of caught water [56]. Monthly rainfall data is used to calculate the supply of water shown in Equation C6.1.3. Equation C6.1.3 -

Q – Annual Volume caught (m^3) A – Roof Area (m^2) R – Rainfall in a month (m) c - Runoff coefficient

The monthly household demand is subtracted from the calculated volume caught for the month giving a total surplus or deficit of the tank in that month. The number of days in deficit in a calendar year is used to determine the volume of water required at the start of the dry season [56]. A safety factor is added to this calculated volume, providing the necessary tank volume capacity[56].

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CP-CBU-125 C6.2 Sizing Roof Area Sizing the required are of the roof is very simple and can be summarised in Equation C6.2.1, when the annually required volume of water is known for the system. Equation C6.2.1 -

Q – Annual Volume caught (m^3)

-

A – Roof Area (m^2)

-

R – Rainfall in a month (m)

-

c - Runoff coefficient

For a system with a fixed roof area, the maximum volume of water that can be harvested in a year can be found using Equation C6.2.2 Equation C6.2.1 -

Q – Annual Volume caught (m^3)

-

A – Roof Area (m^2)

-

R – Rainfall in a month (m)

-

c - Runoff coefficient

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C8 Materials Used in Tank Construction - Priced in Cambodia Material

Unit

Cost/Unit

Cement - small jobs Cement - large jobs Brick – Open Brick – Solid Brick – French Sand Coarser sand Fine Sand Fine Aggregate Coarse Aggregate Concrete Ring 1m diameter ¾’’ metal bar Wire Reo 4mm diameter Wire Reo 1mm diameter Bar Reo 3mm diameter Bar Reo 6mm diameter Bar Reo 8mm diameter ½’’ chicken mesh PVC Pipe 34mm PVC Pipe 21mm PVC Pipe 65mm PVC Pipe 90mm PVC Pipe 100mm PVC Pipe 150mm Corrugated iron sheet Galvanised tin sheet 21mm pipe and tap for drainage Overflow screen Leaf filter Engine Oil Staples Wire 2mm Wood - treated 50mm x 50mm Wood - Bamboo poles thin Wood - Bamboo strips Wood - lopped tree supports

Bag tonne 100 100 # m3 m3 m3 m3 m3 # m3 Kg Kg Kg Kg Kg m2 m m m m m m m2 m2 # # m2 ml # Kg m m m m

5 95 - 100 5.2 5.8 0.08 15 15 15 26 20 8 2 2 2 1 1 1 3 0.4025 0.425 1 1.25 1.625 3.25 0.8 2.2 2 2 5 1.3 1 1 0.03 0.04 0.26

PVC Pipe bends reducer - 100 to 65mm reducer - 50 to 40mm

# #

1 0.75

Comments 20kg bag

1 in x 2 in 4cm x 6cm

Material

Unit

Cost/Unit

reducer - 40 to 35mm 21mm T 90mm T 21mm L 90mm L Box Screws Ball Valve

# # # # # 200 #

0.25 0.7 1 0.2 0.6 2 3

PE Tarpaulin 2x3 3x4 4x5 5x6 Plastic one piece Tarp/liner

# # # # m2

Comments

4 5 6 7 0.4375

4m wide, sold by metre length

5 bar (all), bought in 4m lengths (all pipe) Large Cloth bag Large Plastic Liner bag

Sold in 2.4 x 1.6 m sheets 5C grade Same for 60mm tap Same for 60mm tap 0.6m2 per system 500 staples

bought in 30m lengths Thickness 20mm flat, bought in 85m lengths (approx) bought in 5m lengths

# #

Unavailable in Phnom Penh

First Flush System Ball Pipe Diameter change piece in pipe Tbend Pipe glue

# # # # Kg

0.12 As above As above As above 6

Rope Pump Chain - small Chain - large

# m m

7 2.5 5

day day

10 5

day

Varies

km

0.65

Training and Labour Skilled Labour rate (per day) Unskilled Labour rate (per day) Training unskilled workers up to skilled workers (per day) Transport costs of moving existing tank to site (per km)

Readily available from local NGO's

1 day to 1 week with RWC staff

C9 Individual Tank Costs Table C9.1: Concrete Ring Tank costs Materials Cement Sand Aggregate (10mm*20mm) Aggregate (40mm*60mm) Concrete Ring: 1000mm diameter Wire Reinforcement: 4mm PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Unskilled Labour Skilled Labour

Quantity Bags m3 m3 m3 # kg m # # #

Units 3.5 0.5 0.5 0.9 12 4 0.3 1 1 2

Days Days

Total Cost $17.50 $7.50 $13.00 $18.00 $96.00 $8.00 $0.12 $2.00 $2.00 $4.00

5 15 26 20 8 2 0.4025 2 2 2

3 3

3000

Litres

Cost/Unit

5 10

$15.00 $30.00 Final Cost $213.12 $0.0560

Cost per L Cost per L W Labour

$0.0710

Table C9.2: Tarpaulin Tank costs Materials Wood Mud/clay Tarpaulin - 1 piece liner Wire galvanised sheet Drainage System: 21mm diameter Pump Labour Unskilled Skilled

Litres

Quantity m m3 m2 Kg m2 # # Days Days

5000

Units 30 0 26.31 1 3 2 7

Cost/Unit 0.26 1 0.4375 2 0.78 1 1

5 10

2 2

Cost per L Cost per L W Labour

Total Cost $7.80 $0.00 $11.51 $2.00 $2.34 $2.00 $7.00 $10.00 $20.00 Final Cost $62.65 $0.0065 $0.0125

CP-CBU-125 Table C9.3: Jumbo Jar costs Materials Cement Sand Aggregate: size 10mm x 20mm Aggregate: size 40mm x 60mm Bar reinforcement: 3mm diameter Wire reinforcement: 1mm diameter PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Skilled mason Unskilled labourer

Quantity Bags m3 m3 m3 Kg

Units 5.5 0.8 0.2 0.5 1

Cost/Unit 5 15 26 20 1

Total Cost $27.50 $12.00 $5.20 $10.00 $1.00

Kg

5

2

$10.00

m

0.3

0.4025

$0.12

#

1

2

$2.00

# #

1 1

2 2

$2.00 $2.00

Days Days

3 3

10 5

$30.00 $15.00 Final Cost $116.82 $0.0239

3000

Litres

Cost per L Cost per L W Labour

$0.0389

Table C9.4: Interlocking Block Tank costs Materials Wood (for brick making frame and press) Sand Cement PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Skilled Unskilled

Litres

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Quantity

Units

Cost/Unit

m m3 20kg Bag m # # #

1 0.5 6 0.3 1 1 1

2 15 5 0.4025 2 2 2

$2.00 $7.50 $30.00 $0.12 $2.00 $2.00 $2.00

3 1

10 5

1600

Cost per L Cost per L W Labour

$30.00 $5.00 Final Cost $80.62 $0.0285

Days Days

Total Cost

$0.0504 205

CP-CBU-125 Table C9.5: Semi-Submerged Dome Tank costs Materials Cement Sand 3/4" Metal Bar Brick Drainage System: 21mm diameter

Quantity 20kg Bag m3 m3 # #

Pump Labour Skilled Labour Unskilled Labour

Litres

Units 3.4 0.4 0.1 800 1

Cost/Unit 5 15 2 0.052 2

#

1

7

Days Days

4 12

10 5

Total Cost $17.00 $6.00 $0.20 $41.60 $2.00 $7.00 $40.00 $60.00 Final Cost $173.80 $0.0148

Cost per L Cost per L W Labour

5000

$0.0348

Table C9.6: Closed Frame Ferro-cement Tank costs Materials Cement Sand Aggregate: size 10mm x 20mm Aggregate: size 40mm x 60mm Metal Sheet Frame - reused Wire reinforcement: 1mm diameter PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Skilled mason Unskilled labourer

Litres

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Quantity 20kg Bags m3 m3 m3 m3 Kg m # # # Days Days

3000

Units 5.5 0.8 0.2 0.5 2 10 0.3 1 1 1

Cost/Unit 5 15 26 20 0.5 2 0.4025 2 2 2

Total Cost $27.50 $12.00 $5.20 $10.00 $1.00 $20.00 $0.12 $2.00 $2.00 $2.00

3 3

10 5

$30.00 $15.00 Final Cost $126.82 $0.0273

Cost per L Cost per L W Labour

$0.0423

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CP-CBU-125 Table C9.7: Open Frame Ferro-cement Tank costs Materials

Quantity

Units

Cement Sand Aggregate: size 10mm x 20mm Aggregate: size 40mm x 60mm Metal Sheet Frame - expendable Wire reinforcement: 1mm diameter PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter

20kg Bags m3 m3 m3 m3 Kg m # # #

5.5 0.8 0.2 0.5 2 10 0.3 1 1 1

5 15 26 20 3 2 0.4025 2 2 2

$27.50 $12.00 $5.20 $10.00 $6.00 $20.00 $0.12 $2.00 $2.00 $2.00

3 3

10 5

$30.00 $15.00 Final Cost $131.82 $0.0289

Labour Skilled mason Unskilled labourer

Days Days

Cost per L Cost per L W Labour

3000

Litres

Cost/Unit

Total Cost

$0.0439

Table C9.8: Plate Tank costs Materials Cement Sand Bar Reo for plate mould Aggregate Wood - lopped tree Wire PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Skilled mason Unskilled labourer

Litres

CP-CBU-125

Quantity 20kg Bags m3 kg m3 m kg m # # # Days Days

5000

Units 43 0.8 2 0.09 20 2 0.3 1 1 1

Cost/Unit 5 15 1 26 0.26 1 0.4025 2 2 2

Total Cost $215.00 $12.00 $2.00 $2.21 $5.20 $2.00 $0.12 $2.00 $2.00 $2.00

4 4

10 5

$40.00 $20.00 Final Cost $304.53 $0.0489

Cost per L Cost per L W Labour

$0.0609 207

CP-CBU-125 Table C9.9: Above Ground Mud Tank costs Materials

Quantity

Wood Mud/clay Tarpaulin 5*6 Wire PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter

m m3 # Kg m # # #

Labour Unskilled Skilled

Units

Days Days

5000

Litres

Cost/Unit

Total Cost

150 0 28 1 0.3 1 1 1

0.26 1 0.4375 2 0.4025 2 2 2

$39.00 $0.00 $12.25 $2.00 $0.12 $2.00 $2.00 $2.00

2 6

5 10

$10.00 $60.00 Final Cost $129.37 $0.0119

Cost per L Cost per L W Labour

$0.0259

Table C9.10: Large Partially Underground Dome Tank costs Materials Cement Sand Aggregate Bricks Chicken wire Staples 6mm rebar 8mm rebar Coffee tray mesh - (0.9 wide) Binding wire Pump Labour Labour (skilled) Labour (unskilled)

Litres

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Quantity 20Kg Bag m3 m3 no m2 Number kg kg m kg #

Units 23.25 1 0.085 300 24 3086 4.44 7.89 4.8 1 1

Days Days

9.25 19.25

10800

Cost/Unit 5 15 26 0.06 3 0.0026 1 1 0.06 1 7 10 5

Cost per L Cost per L W Labour

Total Cost $116.25 $15.00 $2.21 $18.00 $72.00 $8.02 $4.44 $7.89 $0.29 $1.00 $7.00 $92.50 $96.25 Final Cost $440.85 $0.0233 $0.0408 208

CP-CBU-125 Table C9.11: Single Skin Externally Reinforced Tank costs Materials

Quantity

Units

Sand Aggregate <50mm Cement 75mm plastic pipe Bricks 90 degree elbow PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter

m3 m3 Bags m no no m # # #

2.5 1.3 6 2 800 1 0.3 1 1 1

Labour (skilled) Labour (unskilled)

Days Days

4 4

Litres

Cost/Unit 15 26 5 1 0.052 0.6 0.4025 2 2 2

$37.50 $33.80 $30.00 $2.00 $41.60 $0.60 $0.12 $2.00 $2.00 $2.00

10 5

$40.00 $20.00 Final Cost $ 211.62 $ 0.0253

Total Cost per L Cost per L W Labour

6000

Total Cost

$ 0.0353

Table C9.12: Pumpkin Tank costs Materials Cement Sand Metal Mould - clay ½" Chicken Mesh PVC pipe: 34mm diameter Tap and PVC socket: 21mm diameter Screen Overflow Drainage System: 21mm diameter Labour Skilled labour Unskilled labour

Litres

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Quantity Units Bag 3.2 m3 1.56 m3 0.17 Kg 5 m2 12 m 0.3 # 1 # 1 # 1 Days Days

5000

3 3

Cost/Unit 5 15 2 1 3 0.4025 2 2 2

Total Cost $16.00 $23.40 $0.34 $5.00 $36.00 $0.12 $2.00 $2.00 $2.00

10 5

$30.00 $15.00 Final Cost $131.86 $0.0174

Cost per L Cost per L W Labour

$0.0264

209

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Appendix D - Education D1 RWC Education Pamphlets

Figure D1.1: Poster highlighting good hygiene and sanitation practices.

Figure D1.2: First part of calendar given to the households.

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Figure D1.3: Second part of calendar given to the households.

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CP-CBU-125 D2 Learning and Teaching Style Booklet This Learning and Teaching Styles booklet was prepared for RWC and given to their WASH program staff during the Project Team’s time in Cambodia. The booklet is included here in its original unedited format.

Grace Lee, Zachary Parsons, Jack Clarke and David Barnes CP-CBU-125

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Table of Contents 1.0 Introduction………………………………..………………………………..…………….2 2.0 Learning Styles……………………………...…………………………………………….3 2.1 Visual learner……………………………...…………………………..…………...3 2.2 Aural learner………………………………………...……………………………..3 2.3 Verbal learner…………………………………………………………….………...3 2.4 Physical learner………………………………………………….…………..……..3 2.5 Logical learner……………………………………………………………………..4 2.6 Social learner…………………………………………………………...………….4 2.7 Solitary learner……………………………………………………………..………4 3.0 Teaching Styles……………………………...……………………………………………5 3.1 Visual teaching style………………………………………………………..……...5 3.2 Aural teaching style………………………………………………………………..5 3.3 Verbal teaching style……………………………………………….……………...6 3.4 Physical teaching style…………………………………………….………….……6 3.5 Logical teaching style……………………………………………………………....7 3.6 Social teaching style………………………………………………………………..7 3.7 Solitary teaching style ……………………………………………..…………..…..8 4.0 Ideas and Suggestions………………….....………..…………….…………………..…10 5.0 References…………………………………….………………………………………..11

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1.0 Introduction Learning styles group common ways that people learn. Each person has a preferred learning style that can influence the way they learn. There are seven main learning styles that include, visual, aural, verbal, physical, logical, social and solitary. Teachers (whether in classrooms or demonstrators showing a group how to use the new equipment) are an important influence when educating others. Effective teaching requires a variety of behaviours and methods according to the students’ knowledge, their learning style and the content of information that is to be learned. The methods of instruction (controlled by the teacher) have a greater affect on learning outcomes than the learner’s characteristics. As such it is important to try and deliver the information/teach in a style that best fits the student/ the majority. Effective and successful teachers not only speak and know the topic (being taught) very well, but also select material that is relevant to the learner. They are able to maximise time and motivate the learners to engage them in the learning process. This booklet will provide a brief summary of the seven learning styles as well as a guideline of the teaching style that best suits the learning style discussed.

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2.0 Learning Styles 2.1 Visual learning A visual learner learns best by watching and seeing. They prefer and like to take in information that are in the form of picture, graphs, slides and demonstrations. Visual learners are able to easily visualise, objects, plans and outcomes. They are able to conjure up the image by seeing it in the “mind’s eye”. Visual learners often have a vivid imagination and can become impatient or drift away when extensive listening is required. They need something to watch. They prefer to use images, colours, maps and pictures to organise information and communicate with others. Visual learners often have good spatial sense, that is, they tend to have a good sense of direction.

2.2 Aural learning An aural learner learns best by listening. They tend to remember and repeat concepts and ideas that are verbally presented. Aural learners learn well through lectures and listening to tapes. They can repeat and/or fulfil verbal instructions well. They can produce words and letter by hearing them and tend to like to talk. Aural learners like to work with sound and music and tend to have a good sense of pitch and rhythm.

2.3 Verbal learning Verbal learning style involves both the written and spoken word. Verbal learners learn best through verbalisation. They tend to find it easy to express themselves in both writing and verbally. They tend to enjoy reading and writing and are usually not quiet for great lengths of time. Verbal learners tend to benefit and enjoy question and answer sessions. 2.4 Physical learning Physical learners learn best by a “hands-on” approach. They like to learn by doing, and having direct involvement. Physical learners tend to involve the senses of touch while learning. They like to piece things together and can often be seen “fiddling” with something or finding reasons to move. Physical learners tend to always want to be “doing” something. They are not very attentive to visual or auditory presentations and can be a poor listener. They like to try things out and like to manipulate objects. Often they are successful with tasks that require manipulation. Physical learners tend to use movement to help concentrate and tend to be active while learning.

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2.5 Logical learning Logical learners like logical and mathematical reasoning. They can recognise patterns and connections between seemingly meaningless content easily. Logical learners tend to like to classify, organise and group information to help them to learn and understa nd. They work well with numbers and typically work through problems and issues in a systematic way. Logical learners like to create itineraries, to-do lists and agendas, and typically rank and number them before putting them into action. Their scientific approach often results with them supporting their points with logical examples or statistics. 2.6 Social learning Social learners prefer and learn best in groups or classes. They tend to be able to communicate well with people, both verbally and non-verbally. Consequently, their learning is heightened by bouncing thoughts off other people and listening to their responses. Social learners prefer to work through problems, issues and ideas with a group as opposed to alone. These individuals have a strong social style and tend to be good listeners.

2.7 Solitary learning Solitary learners are more private and independent. They can concentrate well and focus their thoughts and feelings on current topics. They are aware of their own thinking and tend to analyse the different ways they feel and think. Solitary learners prefer to work on problems alone and somewhere quiet. They prefer to work alone and learn alone using selfstudy. If they spend time with a teacher or instructor, it is only to clarify information that they could not clarify themselves. They tend to spend time on reflecting on past events, and self-analysis. Solitary learners may keep a journal or diary to record their personal thoughts and events.

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3.0 Teaching Styles 3.1 Visual teaching style Visual learners learn best by seeing or watching, as such when teaching visual learners, there should be a focus on the visual media. The visual media needs to stand out. Below is a list that may be useful when teaching visual learners. 

Use colour, layout, and spatial organization in your presentations.

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Use 'visual words' to highlight important points.

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Include pictures, photos and diagrams where possible

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Mind maps is an excellent way of visually conveying different ideas.

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Replace words with pictures and use colour to highlight the important links/points.

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Try use colour and pictures in place of text wherever possible.

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System diagrams can help the learner visualise the links between parts of a system.

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Flow diagrams can help the learner visually see steps in a process/method.

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The visual journey or story technique can help visual learners memorize content that isn't easy to 'see.'

3.2 Aural teaching style Aural learners learn best by listening, as such when teaching aural learners, there should be a focus on the aural aspect of delivery. Below is a list that may be useful when teaching aural learners.

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Use easy to understand language that can clearly convey the idea

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Use sound recordings to provide a background and the learner to be able to visualise the content

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Try to create rhymes or mnemonics (that rhyme) to help aural learners remember content

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Songs and poems may be a useful way to deliver a message to an aural learner

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Use different tones when trying to teach an aural learner

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3.3 Verbal teaching style Verbal learners learn best through verbalisation, as such when teaching verbal learners, there should be a focus on the written and spoken aspect of delivery. Below is a list that may be useful when teaching verbal learners. 

If you are a verbal learner, try the techniques that involve speaking and writing. Find ways to incorporate more speaking and writing in techniques. For example, talk yourself through procedures in the simulator, or use recordings of your content for repetition.

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Make the most of the word-based techniques such as assertions and scripting. Use rhyme and rhythm in your assertions where you can, and be sure to read important ones aloud. Set some key points to a familiar song, jingle or theme.

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Mnemonics are your friends for recalling lists of information. Acronym mnemonics use words, focusing on the first letter of the word to make up another word or memorable sequence. You can also make up phrases using the items you want to memorize.

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Scripting is also powerful for you. You don't just have to write them down. Record your scripts using a tape or digital audio recorder (such as an MP3 player), and use it later for reviews.

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When you read content aloud, make it dramatic and varied. Instead of using a monotone voice to go over a procedure, turn it into a lively and energetic speech worthy of the theatre. Not only does this help your recall, you get to practice your dramatic presence!

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Try working with others and using role-playing to learn verbal exchanges such as negotiations, sales or radio calls.

3.4 Physical teaching style Physical learners learn best by a “hands on” approach. as such when teaching physical learners, there should be a focus on the “hands on” aspect of delivery. Below is a list that may be useful when teaching physical learners. 

Try to create hands-on activities, such as creating, building or deconstructing a model

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Use physical models and objects where possible that the student can touch and feel. Models are a great way for physical learners to learn the functions and process.

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Try to involve the student in writing and drawing (as they are physical activities). Use large sheets of paper and colour markers.

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Use role-playing

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Create a “fill-the-sheet”. Hand out a sheet with information that have blanks where answers need to be filled. During the presentation provide the answers, and give the physical learner enough time to write in the gaps.

3.5 Logical teaching style Logical learners like logical and mathematical reasoning, as such when teaching logical learners, there should be a focus on the logical and mathematical aspects of delivery. Below is a list that may be useful when teaching logical learners. 

Use “lists” whenever possible. For example, use lists when conveying key points

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Use flow charts to show the step-by-step process

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Use statistics and other analysis to help explain a topic

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Show clear links between parts or steps in a process or model.

3.6 Social teaching style Social learners learn best in groups of classes, as such when teaching social learners, there should be a focus on the group work and involvement. Below is a list that may be useful when teaching social learners. 

Try to enable group work and activities where possible

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Try splitting a larger group into smaller groups. Have different stations with different topics, and let the groups rotate from one station to another.

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If possible, have a couple of icebreaker games

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Can use groups to role-play

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Mind mapping is a great group activity, where individuals work together to come up with a plan/diagram, of ideas.

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Promote group discussions

3.7 Solitary teaching style Solitary learners prefer to work alone and independently, as such when teaching solitary learners, these factors should be considered. Below is a list that may be useful when teaching solitary learners. 

While giving a presentation, provide a summary/ written or pictorial information, that the solitary learner can follow through and follow during the presentation

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Provide pamphlets, booklets, posters even stickers that the solitary learner can take home and read and look at their own time.

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Provide them with the opportunity to ask information privately. That is, provide perhaps a number to call or an email address.

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4.0 Ideas and Suggestions To account for the different learning styles of the individuals, perhaps using a mix of media for conveying the content of information. Planning activities which involve a range of verbal, visual, movement elements and “hands on” will consider the majority of the learning styles. Below is a list of some ideas:  Offer different stations where people can choose to go or need to rotate to, one perhaps being a demonstration, another being multiple posters and handouts, another being a video or a lecture/presentation.  Demonstrate the procedure with the use of video and/or physical models.  Perhaps construct a physical model and give the learners an opportunity to deconstruct/play with the model  Perhaps provide pamphlets and booklets with the main key points  Stickers and magnets are an alternative  Strategically placing stickers in specific locations such as above components that require maintenance, to remind the user to clean and maintain that component.  Design handouts where blanks need to be filled out by the learner throughout the presentation  Design a puzzle or game maze showing the process of key points. Perhaps showing the path to safe water  Role play performances  Create a song, or catchy rhyme  Mass media campaigns

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CP-CBU-125 5.0 References Food, Water and Family Health: A Manual for Community Educators United Nations Development Programme World Health Organization., Switzerland: Office of Global and Integrated Environmental Health, 1994, p 104. N.McGinn, and E. Schiefelbein. (2010. Nov.). Learning how teachers learn in underdeveloped countries. Prospects. [Online]. 40(4), pp. 431-445. Available: http://www.springerlink.com/content/d008087xv4w411n3/ M. Elmendorf, and R. Isely, “Public and Private Roles of Women in Water Supply and Sanitation Programs”, Human Organization., vol. 42, no. 3, pp. 195-204, Fall. 1983. (2012). Overview of the Seven Perceptual Styles. Advanogy., [Online]. Available: http://www.learningstyles.org/styles/visual.html (2012). Overview of Learning Styles. Advanogy., [Online]. Available: http://www.learningstyles-online.com/overview/

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D3 Initial Questionnaire This Appendix includes the questionnaire developed for recipients of the RWH tanks in Cambodia. The questionnaire is included as formatted on the original document.

DEMOGRAPHICS 1. How old are you? 2. Sex? 3. How many people living in the household? Children under 5yrs

Children 5-15 yrs

Adult Males

Adult Females

RAINWATER TANKS 1. How long have you had the rainwater tanks? 2. Tell us about the rainwater tanks, what do they do? 3. Have there been any problems with your rainwater tank? a. If yes, what was the problem? b. Were you able to fix it yourself, or did someone else fix it? 4. Are there any parts of the system that need to be cleaned? (tank, roof, first flush device, tap)? 5. Can you describe what you need to do to clean it? 6. Did anyone receive any training, equipment or advice on how to look after the tank? a. If so, what? 7. Is the rainwater system easy to use? Is there anything that is difficult/troublesome? 8. If you could change anything about the rainwater tank system what would it be? 9. What would your ideal water system be? 10. What changes have resulted from having a rainwater tank? 11. Has the rainwater tank affected other aspects of your life? a. Has the average time you spend collecting water changed? If yes, in what way? b. Has this affected the quantity of water available to the household? If yes, how? c. Has it affected the way you use water? If yes, how? 12. Have you had more time free for other activities? 13. Has your income changed as a result of the rainwater tank? 14. What have been the benefits of the rainwater harvesting? 15. What do you think are the disadvantages of the rainwater harvesting? 16. What differences are there between rainwater and other water sources?

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CP-CBU-125 QUALITY OF WATER 1. Describe/tell us about the water from the tanks a. What does it look like? b. Are there any things in it? c. What does it smell like? d. What does it taste like? 2. Do any of these things change throughout the year? a. A few weeks after it has rained? b. When water level in the tank is low/high? 3. What do you use the rainwater for (drinking, bathing, cooking)? 4. Is there anything you do to the water before drinking or using it (treating/boiling)? a. How often? Always, often, rarely, never? b. Why/why not?

WATER REQUIREMENTS 1. 2. 3. 4.

Do you always have enough water for your needs? For bathing, drinking, cooking? If you had more water, what would you use it for? Do you have enough rainwater supply in the wet season? In the dry season? How much water is collected per day?

HEALTH 1. 2. 3. 4. 5. 6. 7.

How do you know that the water is good for you? What makes you think that the water is safe? Does the water you drink affect your health? Has the rainwater tank changed your family’s health? If so, how? Have your children been able to attend school more often? Has the rainwater tank affected the number of days per month you are sick? Have your living conditions changed as a result of the rainwater tank?

STORAGE 1. What is the best way to store water? 2. What should I take into account/consider when storing water? 3. How do you store water at home? If in containers: a. Describe the containers in which you store water for each use b. Are containers inside the house/in the shade or outside the house/in direct sunlight? c. How long is water kept in each container before it is totally emptied?

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CP-CBU-125 d. Do the containers need to be cleaned? If so, how are they cleaned and how often are they cleaned? 4. Did you collect rainwater before your tank was installed? 5 . How did you store water before? Questionnaire for non- recipients of the RWH tanks DEMOGRAPHICS 1. How old are you? 2. Sex? 3. How many people living in the household? Children under 5yrs

Children 5-15 yrs

Adult Males

Adult Females

ACCESS TO WATER 1. 2. 3. 4. 5.

Where do you get water from? When are these water sources available during the year? How far are they from your house? How long does it take to get to the water source? How many trips to each water source do you make a day? Do you have to queue at the water sources? How long do you spend queuing at each water source? 6. Who usually collects water? 7. What do you use the water for? 8. How long do they usually spend each day collecting water? a. How does this change during the wet season? b. How does this change during the dry season? 10. Do you ever have to purchase water in the dry season? a. If yes, how much do you have to pay per load? b. How many times do you need to purchase a load per week? c. How many litres are bought each load? 11. Do you collect or store rainwater for household use? a. How do you collect the rainwater? b. How do you store the rainwater? 12. What would be your ideal water system? QUALITY OF WATER 1. Describe/tell us about the water from the sources a. What does it look like? b. Are there any things in it? c. What does it smell like? d. What does it taste like? CP-CBU-125

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CP-CBU-125 2. Do any of these things change throughout the year? a. A few weeks after it has rained? b. When water level in the tank is low/high? 3. What do you use the rainwater for (drinking, bathing, cooking)? 4. Is there anything you do to the water before drinking or using it (treating/boiling)? a. How often? Always, often, rarely, never? b. Why/why not?

WATER REQUIREMENTS 1. Do you always have enough water for your needs? For bathing, drinking, cooking? 2. If you had more water, what would you use it for?

HEALTH 1. 2. 3. 4. 5. 6. 7.

How do you know that the water is good for you? What makes you think that the water is safe? Does the water you drink affect your health? Has the rainwater tank changed your family’s health? If so, how? Have your children been able to attend school more often? Has the rainwater tank affected the number of days per month you are sick? Have your living conditions changed as a result of the rainwater tank?

STORAGE 1. What is the best way to store water? 2. What should I take into account/consider when storing water? 3. How do you store water at home? If in containers: a. Describe the containers in which you store water for each use b. Are containers inside the house/in the shade or outside the house/in direct sunlight? c. How long is water kept in each container before it is totally emptied? d. Do the containers need to be cleaned? If so, how are they cleaned and how often are they cleaned?

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CP-CBU-125 D 4 Questionnaire for Cambodia To be completed in Cambodia… Four subject areas 1. 2. 3. 4.

Villages Schools Health Centres RWC

Breakdown of research for each area: 1. Objectives 2. Questions 3. Additional information to be obtained What is to be recorded for every interview: - Number of participants - Gender - Age (if possible) - Location/name of Village, School, Health Centre etc - Method of delivery (time, informal/formal, structured/unstructured)

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CP-CBU-125 VILLAGES

Objective: 1) To determine what the water from the rainwater tanks are being used for 2) To identify the impact of having access to clean water 3) To determine if the households are practical good sanitation practice (e.g.boil water) 4) To identify if the if the tank is maintained, and who is responsible for maintenance 5) To determine if there are any issues with the tanks

Questions for non-recipients of RWH tanks 1. Can you please tell me about the rainwater tanks, what do they do?

2. Have there been any problems with your tank?

3. Are there any parts that need to be cleaned?

4. Did anyone receive any training or advice on how to look after the tank?

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CP-CBU-125 5. What is the best way someone can teach another person how to look after the tank (picture, photos, show)?

6. Can you describe what you need to do to clean it?

7. Is the rainwater tank easy to use?

8. Is there anything that is difficult/troublesome?

9. If you could change anything about the system what would it be?

10.

If you could create and design any system/process to get water, what would it be?

11.

How did you collect the water before you had the rainwater tank?

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CP-CBU-125 12.

Is rainwater good for me and you to drink? How do you know?

13.

Has the water you drink affected your health?

14.

What do you use rainwater for?

15. Do you or your members of your family often have to drink unclean water? What can you do to make it clean?

Questions for non-recipients of RWH tanks 1. How do you collect your water?

2. How long does it take you to collect water?

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CP-CBU-125 3. Who usually collects the water?

4. What is the water used for?

5. What water do you consider is the best to drink and cook with?

6. Why? Is it good for me and you?

7. How do you know?

8. Has drinking this good source of water affected your health?

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CP-CBU-125 9. How do you get access to it?

10.

If you could create and design any system/process to get water, what would it be?

11.

What would you like to change about how your family gets drinking water?

12.

Do you or members of your family often have to drink unclean water?

13.

What can you do to make it clean?

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CP-CBU-125 SCHOOLS

Objectives: 1) To identify if the school teaches sanitation and hygiene gain an insight into what they learn about hygiene and water 2) To identify whether children are able to motivate and teach their parents about what they have learnt 3) To identify if the if the tank is maintained, and who is responsible for maintenance 4) To determine if there are any issues with the tank

Questions 1. What do the children learn at school?

2. What type of hygiene education are they receiving?

3. Do you think they are practicing what they have learnt at home?

4. What methods have worked well when teaching students?

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CP-CBU-125 5. Have you been able to notice any difference/changes with the children’s hygiene practices since teaching?

6. If you could teach the children about hygiene in any way you want, how would you teach them?

7. Do their parents have good hygiene education?

8. Do you think the children teach their parents?

9. If you had to teach their parents about hygiene what do you think would be the best way?

10. How would you go about teaching hygiene to their parents?

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CP-CBU-125 11. What do you think is the best method to teach elderly people who have not had the opportunity of education about hygiene?

12. Are there many students who have rainwater tanks at home?

13. Do the children understand how the tanks work?

14. Do the children know what maintenance is required (cleaning the bottom of the first flush)?

15. Who maintains the rainwater tanks?

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CP-CBU-125 16. Have there been any issues with the tanks?

17. If you could create and design any system/process to get water, what would it be?

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CP-CBU-125 HEALTH CENTRES

Objectives: 1) To visit health centres and identity the sickness that causes the highest number of visits to the health centre 2) To identify if the health centre educates their patients about hygiene and water 3) To identify if the if the tank is maintained, and who is responsible for maintenance 4) To determine if there are any issues with the tanks

Questions 1. What are the common sicknesses?

2. Do you think the water is the main cause?

3. Has there been an improvement in health with the installation of rainwater tanks?

4. Is there a difference between health with those who have access to rainwater harvesting tanks?

5. Do the patients have good hygiene practice, why do you think so?

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CP-CBU-125 6. What do you think is the best way to teach them about hygiene?

7. What does the health centre offer to help with hygiene?

8. Who maintains the rainwater tanks?

9. Have there been any issues with the tanks?

10. If you could create and design any system/process to get water, what would it be?

Information to be obtained:   

Hygiene programs and services offered (summary) Pamphlets and brochures regarding hygiene Statistical information of water-related sicknesses/trends on improvement in health

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CP-CBU-125 Rainwater Cambodia

Objectives: 1) To visit RWC and identify in detail their current education program 2) To determine all parties that are involved with the education aspect of RWC 3) To identify the successes, failures and issues associated with the education program 4) To identify their opinion on the recipients attitudes and values with regards to RWH 5) To determine any other issues RWC encounter 6) To determine what RWC wants

Questions 1. What are the key issues?

2. Why do you think there is a lack of maintenance?

3. What do you think is the overall attitude of the locals, recipients of RWH, non-recipients of RWH?

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CP-CBU-125 4. How to the elderly learn best/best teaching method with different levels of education?

5. Who is responsible for the education aspect, who does the designs etc

6. What has worked well with the education pamphlets and programs?

7. What has not worked well with the education pamphlets and programs

8. Why do you think so?

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CP-CBU-125 9. If you had a group from Australia that could spend one year helping RWC, what would you like them to help you with?

Information to be obtained:     

Previous studies done Information on the number of maintenance issues over a particular period Current education programs (detailed summary of each) Current training programs (summary) Other non RWC programs implemented

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CP-CBU-125 D5 Notes and Findings from interviews and discussions Notes from visit to Health Centre               

Spoke to the director of the health centre The staff members are responsible for maintenance The staff members take turn to maintain the system The health centre has a hygiene and sanitation program where they teach patients about the correct practices The centre has a committee of nine people who conduct the program the majority of patients that come to the health centre have diarrhoea since the program has been implemented, there has been a decrease in the number of people coming to the health centre with diarrhoea 300-400 patients per month RWC gave them posters and leaflets, which the director used to teach the committee members, who then teach the patients A high percentage of the patients with diarrhoea were under the age of 5 and “light weight” The ferro-cement tank was installed in 2010 The health centre also has a hand washing station The rainwater is used for drinking and washing patients Technical issue: water exits through air vent in pipe, which is above the door, hence water flows into the hospital. Investigated issue and realised that first flush system was blocked

Quotes -

“since RWC install tanks, there is clean water, less people with diarrhoea” “less diarrhoea since sanitation program” “After Rainwater Cambodia come her more community have more understanding about drinking water and hygiene”

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CP-CBU-125 Notes from visit to school          

    

 

Spoke to the principal of the school Tank was installed in 2011 The tank holds 330000L NGO CSCS came to the school 3 years ago and taught the teachers and students about hygiene and sanitation. The school teaches hygiene and sanitation every Thursday for 2 hours The learn by practical action of washing hands, writing, painting or verbal The children practice washing their hands everyday in the classroom Rainwater from the tank is directed to 2 drinking stations and 2 hand washing stations Water is collected in a bucket and placed through a water filter , located in the classroom Before the tank was installed, water was obtained from the wells on the school property, however quality of the water wasn’t very good, so they had to buy water from private company/person who sells bottle water. The tanks supplies water for 6 months of the year, the school purchases water for the remainder of the month The children do not have to pay to attend school 300 students ranging from age 5 to 16 years old The school teaches Year 1 to year 9 As the students were on vacation the school was quite empty and bare, nonetheless principal said that when school returns, posters of hygiene and sanitation are placed all around the school Phnom Penh parents teach their children to wash their hands as most have some level of education. The schools teaches the 6 step process for washing hands

Quotes -

“before tank installed, had to pay for water, very expensive” When talk to Sokhol, and asked whether or not Cambodia has improved in the last 10 years, he replied “yes improve but little in hygiene” when asked why, “people don’t want to listen to NGO or TV as like to watch movie and no money to build latrines”

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CP-CBU-125 Notes from visit to Village General   

Village of Kraingserey, Kirivong commune, Phnom Srouch District 61 households/families, 25 with tanks installed UNDP created a pond/water storage 3km away that stores and collects rainwater. Pipes lead from pond to households, so many have access to rainwater. The water is enough during the wet season, but does run out during the dry season RWC taught and trained 3 people in the village to become the technicians Village has a committee consisting of 5 people to maintain the tanks

 

Quotes: “UNDP built pond and pipe water system to supply village. We boil or filter rainwater before drinking” “25 families in the village have four tanks each”

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First Household     

4 tanks installed in 2005 and 2006 Family always boils their water before they drink Use the rainwater for drinking and cooking Before the tanks were installed, the family collected the rainwater from the pond The family had to walk for 3 hrs (return trip) and collected a 200L drum, which would last just for one day 7 people in the household



Issues: -

Ball in the first flush system broke, by shrinkage (as it was made out of plastic) and had been in the tank for 7 years. Seal was brittle, consequently could not be removed

Quotes: -

When asked about the difference between rainwater and pond water, the spokesperson for the family (male) said “rainwater tastier” “When i have tank my health and family improve” “I use the spare time to work and study at health centre” “Family with no tank collect pond water in their village”

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CP-CBU-125 Second Household       

Had a jumbo jar tank Rainwater in the jumbo jar last all year for cooking and drinking The household uses the water from the well (200m away) for washing Custom jars were used to collect rainwater without the first flush system. The water from the jars is boiled and used for cooking. 9 people in the household The 3+ hrs saved from collecting the water is now being used for work

Issues: -

Technically the system was working well, however the drainage hole was blocked as the household placed a twig in there to prevent wasting water.

Quotes: “people boil water because NGO educates community” When asking in-field engineer James Oakley about the possible reason behind people getting sick is responded that a “fundamental cause if lack of education”, and also convenience. Gave us the situation where people who have work hours in the heat and sun in the rice field would rarely collect the water, boil it, wait for it to cool, then drink. Instead they would drink a small amount of refreshing cold water from the pond. “I block the hole in the [in the first flush] because it wastes too much water” “I never take the stick out”

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-

Third Household  

8 people in the household Interesting that the lady also knew the fact that there were 25 households that received rainwater tanks Never run out of drinking water for the year The rainwater from the tanks were used for drinking The rainwater collected in the custom jars were used for cooking There was a pond located 5m behind the house which they used for washing Before the tanks were installed, the family had to collect water from the mountains. The trip to the mountain took 30mins, and the queue to collect the water could be up to 2 hrs. The trip to collect water was done every day

      

Issues: -

First flush was not present as apparently had broken due to the wind The first flush could not be replaced as the family had no money

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CP-CBU-125 Quotes: -

Since having rainwater, the lady said that her husband “no need to go to doctors so much anymore” “when get water from mountain more diarrhoea” When asked whether other families without tanks get diarrhoea she said “always get sick” “many NGO come to teach about sanitation and hygiene” “learn to boil water from NGO” “When I receive a tank I very happy because I get less sick and I know more about sanitation” “NGO organise training” “Go to pond to wash. It is 5m away” “With the spare time I do more agriculture and look after the kids more” “Since tank kids get no diarrhoea” “I have clean water but this does not fix my income problem. I am still very poor” “I decided to get the tank myself” “All members of the family maintain the tank” “All members of the family go to learn sanitation. We take in turns to go”

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CP-CBU-125 Notes from visit to Rainwater Cambodia General  

8 employees, 5 contractors that are taught/trained to build and install tanks People are encouraged to buy the tanks

Observation, Findings, Experience   

Schools that do not have the assistance of a NGO or WASH program can not implement the programs because they do not have enough money People believe that rainwater is better than pond water If households don’t have tanks, they tend to collect rainwater in custom jars

Education    



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Good curriculum/program but an issue is the real practice It is very common to have children drop out of school and help their family (either farming or fishing) Consequently schools need to be flexible RWC provides posters and leaflets that have pictures of the process of washing hands, good sanitation and hygiene practice, diseases that could result from drinking contaminated water Marketing and promotion goes to the community and asks them what they think about the problem of clean water, they then show the community the tank system and encourage/ advise them to invest in the system. Issue: when teaching the elderly, many do not listen to those who are younger. However after showing pictures and being able to prove the consequences, the elderly are more accepting to what was being advised and encouraged

Education program:  

    

RWC follows the national standards of what to teach the community for sanitation and hygiene They follow/are guided by CLTS (community led total sanitation), that outlines that there are 7 important steps that should be done during the sanitation and hygiene program. They follow/guided by BCC (Behaviour Change Community) and PHAST (participatory hygiene and sanitation transformation) RWC has a program officer that works on the water, sanitation and hygiene programs Hopes to (in the future) include environment in the program as well The programs and all funded by other organisations The program officers and those involved with WASH programs, attend training by the Ministry of Rural Development

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CP-CBU-125   

   

The teaching focuses on the 7 steps, community facilitation (local authorities) and school facilitation (teachers) At present only the community has been targeted for the WASH programs, RWC is currently working on the programs for the school. Once a month the (sub) groups (about 20) that are involved with WASH programs/marketing/work with schools and the community, meet and discuss their current progress and new findings. RWC collaborates with department of rural development, and conducts training with the key promoter, who in turn works with the selected commune council members 5 members from each village make up the Village Development Committee The members are responsible for conducting the program within the village, while the key promoter reviews their work and follows up The 7 step program outline for a community 1) Village Mapping for Communities: - Ask village to map the household, infrastructure, which households have latrines, and households that do not have latrines 2) Calculation of amount of faeces produced: - Faeces are weighed, and calculations as to how many kilos of faeces are produced in 1 week, 1 month, 1 year. 3) Defecation Transect Walk - Everyone walks around the village and places a mark where there are faeces. - A strand of hair is taken, swiped across the faeces and placed into a glass of water. The facilitator then asks people would you drink this water. Everyone replies with no. - This action helps the villages realise the open defecation contributes to contaminated water that they drink, cook and wash with. - A small object representing fly feet is then placed on the faeces then put on a plate of food - Similar to the hair and water situation, villagers are asked whether or not they would eat the food on the plate. 4) Analysis of the ways of Infection and how to prevent: - The types of diseases and infection that could result from unhygienic practices and contaminated food and water are shown - Ways of prevention including boiling the water before drinking or cooking, 5) Calculating medical expense: - One person is asked to volunteer to provide details of who has been sick in the family, how long they were sick for and an approximation of the costs of medical expenses

For the elderly and women 6) Carrying a Child:

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CP-CBU-125 -

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Villagers are advised that they should carry children, and not let them crawl on the ground that is contaminated with faeces 7) Village planning to construct/achieve/latrine Many villages after the program build a latrine

For the children 

7 step program is exactly the same for all steps except the last two 6) Children produce messages/slogans 7) Children walk around the community and shout slogan to Adult group

Issues   

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People steal the bicycle pumps at schools (these pumps are installed at schools and health centres as it is required to pump the water out) Rainwater quality is good, but quantity is not enough (due to rainwater being used for other purposes besides drinking and cooking) People don’t purchase the tanks because 1) can’t afford it 2) can afford but prefer to use money for other things 3) given a limited time to make payment (as RWC has a time constraint on project work), and can not save/earn enough money to purchase the tank during that period RWC does not have enough funds to be able to do everything they want to do Cost of tanks is an issue that prevents enough water to be stored for the whole year People go to the alternative water sources (e.g. pond) and place the contaminated water in the tanks. The locals understand that rainwater is good for them. When the water is easy to access, some tend to use it for all purposes (not just for drinking and cooking as instructed), they then realise that they have run out of rainwater, then refill the tanks with contaminated water from alternative sources “wife has to get approval from husband”, men decision maker Lack of participation, as program not compulsory Women and children join, but hard to encourage men “Old men/elderly don’t respect young guys” “Donor expectation too big”, too high. Which is why the RWC members teach key promoters who teach 5 commune members who then teach everyone…message passed along. Limited time to send message. “Limitation on knowledge of transformation” limit on knowledge of how to work with people who do are not interested. Program doesn't work for a few rural communities “old generation thinking and habit” “rural want to generate income and solve problem once sick” not prevent from sickness Elderly listen to local authority…power is one way, but do not really want to force, want people to understand, which is why RWC tries to get the commune council, district on board, the use power.

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CP-CBU-125 

 

No enough money to have continuous monitoring and input of education program,, can not follow up. After the latrine program, ask who think about installing latrine, many say yes, but never know if they do “When ask if people wash hands everyone says yes when asked how many times, rarely, and not so much” Implement program in village, problem is that village don't have money and no product in place

Technical 

Field officer is responsible for guiding and managing system during construction

What RWC would like   

Regular evaluation of the systems that have been installed as RWC has not had the time, money, and people to conduct such an evaluation Research is needed to identify the successes, failures, impacts of benefits, technically and socially, environmental Ideal to build a tank that is large enough to store rainwater for all purposes (drinking, cooking, washing and cleaning)

Quotes: -

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“When we apply for funding we detail our project and if it fits in the scope of an organisation like Aus aid we get the funding. There is more of a push for follow up so it is an option to do less tanks and follow up more” in field volunteer James Oakley “2 years after we visit, the first flush system is all gone and we don’t know why” Rural villages “they know that rainwater is good, and prefer to drink rainwater, but we don’t understand why no maintenance”

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CP-CBU-125 D 6 Research Process Research Data was collected through interviews. The team visited a health centre, a school in Phnom Penh, and the non-government organisation, RWC. A total of 4 members of RWC were interviewed, the director of the Health Centre, the principal of the school and 3 households from the Village of Kraingserey. Aims The aims are categorised into 4 categories. Each category has their respective objectives 1. RWC  To identify in detail their current education program  To identify RWC’s opinion on the locals attitudes and values with regards to rainwater harvesting and rainwater.  To identify issues that RWC encounter  To determine what work/projects RWC would like future groups to work on 2. Village Households    

To identify the benefits since obtaining the rainwater tanks To identify whether households carry out any safe water practices To determine what the households use the rainwater for To identify any technical issues the households have encountered with the system

3. Health Centre    

To identify the sickness that causes the highest number of visits to the health centre To identify if the health centre educates their patients about hygiene and water To identify if the if the tank is maintained, and who is responsible for maintenance To determine if there are any issues with the tanks

4. School  To identify if the school teaches sanitation and hygiene gain an insight into what they learn about hygiene and water  To identify whether children are able to motivate and teach their parents about what they have learnt  To identify if the if the tank is maintained, and who is responsible for maintenance  To determine if there are any issues with the tank

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CP-CBU-125 Design The research project involved structured interviews with members of RWC and unstructured and informal interviews/conversations with village locals and the directors from the health centre and the school. The research included both qualitative elements and the following methods were used:   

Structured interviews Unstructured and informal conversations Observations

Setting The study was conducted in Phnom Penh Cambodia and the Village of Kraingserey (data collection took place between 16 th September 2012 and 20 th September 2012.

Participants The initial study proposal required 10-15 recipient and non-recipient households to participate in the interview. However, due to the time constraint and no postgraduate study in this area and Human Ethics Research Approval, EWB suggested that the research be formally conducted only with members of RWC. In total, 9 participants were involved in the research project, consisting of:  4 formally interviewed from RWC  3 informally interviewed from the Village of Kraingserey  1 informally interviewed from a health centre  1 informally interviewed from a school Consent Process In order to obtain consent, EWB in-field engineer James Oakley asked the members of RWC if they would like to participate in the research. Consent was verbally approved and acknowledged. Consent for the villagers, health centre and school was asked by Rainwater Cambodia, similarly consent was verbally approved and acknowledged.

Translation and Piloting The interview guides were initially prepared in English and reviewed by Associate Professor Jim Black from the Nossal Ethics of Global Health for content and cultural acceptability. The interview used simple language containing both closed and open questions. There was no need to translate the documents into Khmer as all the members of RWC had a basic understanding of English. The questions for the informal interviews were translated during the conversations. CP-CBU-125

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CP-CBU-125 The data collection team for the structured and formal interview was composed of one student from the Project Team. The data collection team was composed of 2 students from the Project Team and one translator who worked with RWC and was a native Khmer speaker. The formal interviews with member of RWC provided insight into the community’s attitudes towards rainwater, an insight to the issues they have encountered and are currently present, and work they would like future groups to work on (see Appendix D.3 for initial interview guide). The structured interviews ran for approximately 45 minutes to an hour, and were all located at RWC’s head office in Phnom Penh. The formal and informal interview questions were carefully structured so as not to lead the participants in their answers. The study design was formulated and the interview guide developed before the student researcher’s arrival in Cambodia.

Analysis Participant answers from the structured interviews were transcribed directly into a field research data book. Quotes from the unstructured and informal conversations were directly recorded onto a digital device (an I phone), while the answers were written into the data book, but not immediately.

Use Overall this study obtained valuable information for RWC, by identifying the technical and social issues. The study also obtained valuable information for future groups and individuals who will be working with the organisation, and may be useful to better address the needs of Rainwater Cambodia.

Limitations A significant limitation to the study was the limited number of participants with the majority being employees of RWC. The study’s limitations also centred around cross-cultural research and the complications arising from translation, language and differences in cultural norms. For the informal interviews, the questions were conducted in English and translated into Khmer by members of RWC. The back-and-forth translation from English to Khmer in addition to the Khmer translator not being fluent in English made the informal conversations difficult. There were many difficulties with the translation as the Khmer translator was not fluent in English, thus many times did not understand the questions asked. The open-ended questions allowed participants to give unprompted responses, however due to the language barrier and translation difficulties, questions were partially understood by participants and at times considered vague. A more direct line of questioning is recommended for future studies with a translator who is fluent in English and Khmer. CP-CBU-125

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CP-CBU-125 D7 RWC’s Community WASH Program The table below summarises the 7 steps of the sanitation and hygiene program. The villagers who choose to participate in the program (mainly women, the elderly a children) are divided into two groups, one for the elderly and women and the other for children. The duration of the program is about 2-2.5 hours. Steps 6 and 7 differ depending on the group. Step 1

2

3

4

Task Village Mapping for Communities: First step is to ask the villagers to map the households and infrastructure of the village, including households that have latrines and households that do not have latrines. Calculation of amount of faeces produced Samples of faeces are collected and weighed. Calculations are made to calculate the quantity of faeces that would be produced in 1 week, 1 month and 1 year. Defecation Transect Walk This is considered to be the most challenging step of the program (for the facilitators) as many of the participants hesitate and do not like this step Step 2 involves everyone walking around the village and marking area where there are faeces. This step enables the community to visually see the many different places where there is open defecation; it is eye-opener for many villagers A strand of hair is taken, swiped across the faeces and placed into a glass of water. The facilitator then asks the villagers if they would drink this water. This action helps the villagers realise that open defecation contributes to the contaminated water that they drink, cook and wash with. A small object representing fly feet is then placed on the faeces then put on a plate of food Similarly to the hair and water situation, villagers are asked whether or not they would eat the food on the plate. This action teaches them that flies can contaminate uncovered food, hence food should be covered at all times. Analysis of the ways of Infection and how to prevent The types of diseases and infection that could result from unhygienic practices and contaminated food and water are discussed, and the consequences and effects are visually shown through pictures. The villagers are then educated on the different methods of prevention including boiling the water before drinking or cooking, washing hands, using a toilet and covering food.

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5

6

7

Calculating medical expense One villager is asked to volunteer to provide details of who has been sick in the family, how long they were sick for and an approximation of the costs of medical expenses. The cost of the medical expenses is calculated for the year. This step highlights to the villagers the cost of being sick that could be reduced if they were to follow safe hygiene and sanitation practices. For the elderly and women Carrying a Child Villagers are advised that they should carry their children and not let them crawl on the ground that is contaminated with faeces For the children Children produce messages/slogans Children create messages and slogans that are related to hygiene and sanitation For the elderly and women Village plan to construct/achieve/latrine After the program some villagers build a latrine, others do not For the children The Walk Children walk around the community and shout the slogans/messages, particularly to those who did not attend program (men)

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Visual Outline of the 7 steps

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CP-CBU-125 D8 RWC’s posters

Figure D8.1: Faecal contaminant path educational poster.

Figure D8.2: Hand-washing educational poster. D9 Flow Chart of the roles involved in the WASH Program

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Figure D9.1: Flow chart of the roles in the WASH program.

D10 Health Centre Poster

Figure D10.1: An educational poster from the health care centre.

D11 Education Pamphlet

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Figure D11.1: Page 1 of the revised educational WASH calendar for RWC

Figure D11.1: Page 2 of the revised educational WASH calendar for RWC

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Figure D11.1: Page 3 of the revised educational WASH calendar for RWC

D12 Education Model

Figure D12.1: Educational model design for RWC. CP-CBU-125

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Appendix E - Tank Construction Manuals This appendix contains construction manuals for the tank designs which have been recommended for further research. No construction manual has been altered by the Project Team; the construction manuals are presented as they were from the original author. It is recommended that thorough research, analysis and testing is undertaken before implementing any design.

Table E.1: List on construction manuals included in Appendix D Tank Construction Manual Tarpaulin Tank Pumpkin Tank Semi-Submerged Dome Tank Single Skin Externally Reinforced Tank Large Partially Below Ground Tank

CP-CBU-125

Source ACORD [65]

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CP-CBU-125 E1 - The Tarpaulin Tank An adaption by the Project Team, University of Melbourne, of the ACORD Tarpaulin tank design (1997). All images and reference material was sourced from [78]. Size hole 6m3 Water volume 5m3 Main Costs Oil, galvanised sheeting, tarpaulin, nails, pump (optional – likely hand pump)

Construction Method 1. A 3m x 2m x 1m deep hole is dug with slightly deeper and recessed shaft holes for the support columns. The columns are then dipped in oil for termite protection and placed in the recessed holes. The frames is then tied/nailed together depending on what is freely available.

Figure E1.1: Digging the trench

2. There has been some issues in the past with termites eating away at the organic material (wood) used as the support structure. One solution proposed by [65] is to coat both the poles (as above) and hole surface in oil. CP-CBU-125

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Figure E1.2: Coating the poles and surface with oil 3. The roof beams are added to the frame. The poles are constructed so as to allow a sloped roof for water runoff.

Figure E1.3: Coating Sloped roof beams

4. The wall is filled out with available wood and tied/nailed to the frame on the inside and outside. This forms a 3d space for the wall to be built in.

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Figure E1.4: Wall filled out 5. Mud, grass and other organic material is made into a clay-like mixture. The mixture needs to be solid and firm once dry. It will be based on whatever is available, but the bulk of the material will be the excavated dirt/mud from the tank hole.

Figure E1.5: Organic material from the dug hole made into clay

6. Fill the walls with the organic mud. The structure should now be rigid.

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Figure E1.6: Clay packed into the walls 7. Insert the liner bag and attach it to the walls. If the tarp has holes in the edges these should be used for attachment. The walls are then covered in plastic bag material or anything else that will prevent mud from falling into the water.

Figure E1.7: Liner bag inserted and attached to the walls

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CP-CBU-125 8. Find appropriate roofing material and attach the roof. It need not be made from metal sheeting, but must be waterproof and prevent debris from entering the tank from above.

Figure E1.8: Water proof roof attached 9. The image below shows the water access door. Ideally this would be replaced by a simple hand, bike or rope pump to prevent contamination. If costs must be kept to an absolute minimum however, this is a necessary option.

Figure E1.9: Access door.

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CP-CBU-125 10. The finished tank should resemble Figure E1.10.

Figure E1.10: Completed tarpaulin tank.

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CP-CBU-125 E2 Tarpaulin Tank Constructed by the Project Team in Rural Victoria This manual outlines the construction of a low cost Tarpaulin Tank for a RainWater Harvesting (RWH) system. The design is an adaption of an ACORD design documented by [65]. The original concept and accompanying images can be located in Appendix E. The images and instructions presented here are the authors own, based on construction of the Tarpaulin Tank in rural Victoria, Australia. Size The tank should be made to accommodate the size of the tarpaulin (tarp) available. The design is fully scalable to match the size of the tarp available. In doing so the amount of wasted effort in construction of walls which do not increase storage capacity is minimised. This will be further explained in later sections of the manual. Materials The materials required for the construction of a variety of tank sizes are shown below. The calculations here are based on one actual constructed tank in each location. The different sizes are estimates of materials that have then been costed at local merchants. The tarp ideally is made from polyethylene, must be one piece and free from holes. A polyethylene coated fibre weave tarp was used to construct the tarp tank in Australia. The tarp was successful, but it is unknown how durable the thin polypropylene seal will be over time. Figure E2.1 shows a comparison of the different tarp materials.

Figure E2.1: The polyethylene coated fibre weave tarp (left) compared to the one piece polyethylene tarp (right) [80].

The other materials of note are simple 1-2mm diameter multi-purpose wire and the roofing material. This is used to attach the organic wooden frame together and to build the wall scaffolding. The roof in this design is a single sheet of galvanised tin sheeting. This was used for its simplicity and low cost in Australia. If the sheeting adds too much cost to the design in a specific context, it can be replaced using any waterproof, durable material. CP-CBU-125

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CP-CBU-125 Materials Costs Table E2: Cost Analysis of the Project Team’s Tarpaulin Tank

Material Tarp

1m3 tank Quantity Cost 1x (3m x 3m) $8

2m3 tank Quantity Cost 1x (3.8m x $18 3.8m) 70m $6 2 1.6m $10 800x 1.4m lengths (or equivalent)

3m3 tank Quantity Cost 1x (4.3m x $35 4.3m) 100m $8 2 2m $15 1000x 1.6m lengths (or equivalent) 2.5m3 -

Wire* 50m $4 2 Tin Sheet* 1.2m $5 Bamboo (or other 600x 1.2m lightweight, lengths (or strong, thin and equivalent) straight material) Grass (or other 1.5m3 2m3 fibrous organic material) *Note: Costs for these materials are an estimate only as they were obtained free of charge from a local property owner. **All costs are in Australian Dollars. Equipment        

Shovel Pick Straight crowbar (for breaking hard ground) Pliers Wood Saw Hatchet/Machete Tape measure Wheelbarrow or cart

Figure E2.2: The polyethylene coated fibre weave tarp (left) compared to the one piece polyethylene tarp (right) [80].

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Construction 1. Measure up the hole to be dug based on the size of the tarp. Use Figure E2.3 to size the hole based on the tarp dimensions.

W L

W L

D

D

Figure E2.3: Templates for sizing the hole based on the tarp size. Length (L), Width (W) and Depth (D) of the tank are labelled

2. Dig the hole. Note that the sides should be kept as straight as possible to minimise extra work later in construction. The hole should be dug to measure L x W x 0.5D.

Figure E2.4: Digging the rectangular shaped hole for the tank.

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CP-CBU-125 3. Locate and cut to length the timber support beams that will form the tank frame. The horizontal beams should be 300mm longer than the length (L) of the tank base. The crossbeams should be 200mm longer than the width (W) of the tank. The vertical beams should be 400mm longer than the depth (D) of the tank base.

Figure E2.5: The timber lengths that make up the tank frame.

4. Dig holes for the vertical timber beams in the corners of the tank hole. If the hole/tarp shape is rectangular consider an extra set of vertical beams in the centre of the length L. The location of the holes is critical. The distance that the holes for the vertical beams are away from the tank hole itself is important. This allows enough room for the scaffolding to go in place without being above the hole. This scaffolding will eventually become the wall of the tank and it cannot be built over a hole. The holes should be dug to the depth (D) of the hole plus an additional 400mm. Each pair of holes should be dug an additional 50mm deeper than the previous set, in order to create a sloping roof. See Figure E2.6 and Figure E2.7 for further details.

Hole

Vertical timber poles

Wall scaffolding Figure E2.6: Plan (Top down) drawing of the hole and tank setup.

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Hole

Ground Figure E2.7: Elevation (side) drawing of the hole and tank setup.

5. Insert the vertical beams into the holes. Attach the horizontal beams and cross-beams as shown in Figure E2.8. The timber beams are tied in place using wire and a set of pliers. Adjust the frame as it is being assembled to make sure a slight slope across the roof is maintained. Once the frame is aligned perfectly fill in the holes around the vertical support beams. Use the opposite end of the shovel or pick as a ram to compact the earth down into the hole. In the absence of concrete this is an important step in creating a stable frame.

Figure E2.8: The assembled timber frame and the vertical beam holes being filled in.

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CP-CBU-125 6. Construct the wall scaffolding. This is easiest done on 3 sides of the tank simultaneously, with the fourth side completed last, to allow easy access in and out of the hole. The wall is constructed by using wire to tie the bamboo lengths to the support beams, in a cell pattern as shown in Figure E2.9 and Figure E2.10. The cells created in the scaffolding should have dimensions no greater than and . This will change with soil type, but for the Australian soil with minimal clay content any larger cell size was found to be too large to contain the slurry.

Figure E2.9: The wall scaffolding

Figure E2.10: The cell structure of the scaffolding wall and the wire attachment to the support structure.

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CP-CBU-125 7. Create the slurry. Figure E2.11 shows the final product. The slurry is made from soil dug from the excavation of the hole, organic plant material such as grass or hay, and a small amount of water. Care must be taken not to make the slurry too wet such that it loses too much viscosity and behaves like a thick fluid. The slurry must have just enough water content to allow it to stick together when compacted. This will be dependent on the type of soil in the area in which the tank is to be constructed. The amount of organic material in the slurry is also important. The fibrous materials (such as grass, leaves, straw) act to bind the slurry together. This is the same mechanism used in mud brick construction. Figure E2.12 shows the contrast in quality between a wall constructed with high water, low organic matter content and an optimal organic matter and water content slurry.

Figure E2.11: The slurry used to build the walls of the tank.

Correct slurry

Slurry too wet, not enough organic material Figure E2.12: The scaffolding being filled with the slurry mix to create the tank walls. Note the difference the slurry mix makes on the quality of the wall.

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CP-CBU-125 8. Place the tarp into the hole, making sure it reaches all the corners. Care should be taken to avoid the tarp catching on any protruding objects. Rings in the end of the tarp should be secured to the horizontal cross-beams using wire. Note that this connection should be somewhat loose, allowing some margin for error in the construction of the tank. Once the tank is filled with water the tarp should not be pulling on this ring connection, as this increases the risk of the tarp tearing.

Figure E2.13: The tarp being attached to the tank (left) and the tarp tank once half full of water (right). It should be noted that the tarp used initially in the photos shown in Figure E2.13 was slightly smaller than desired. The tarp doesn’t quite reach the top of the tank and this situation should be avoided. 9. The tank is now complete and can be piped into the household RWH system.

Figure E2.14: The final Tarpaulin Tank

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CP-CBU-125 Review and Conclusions This report shows that the tarp can be constructed from the most basic materials for a very low cost. It also shows that the tank can be constructed by people with no previous experience or technical training, just a thorough understanding of the design. The Project Team believe that this manual can be used to convey the tank design effectively, so that other may reproduce this tank for RWH in low income areas. The Project Team recommend that the tarpaulin tank be considered in low income countries where the primary factor preventing the uptake of RWH is initial costs associated with the construction of the tank. The authors also believe the tank has value as a secondary storage system to accompany an existing high quality system, such as a Thai Jar or Concrete Ring Tank. The tarp tank is inexpensive to install and would provide the extra storage required in monsoonal climates to extend water supply throughout the dry season.

Modifications and Concerns The original ACORD design [65] utilises a bucket system to fetch water from the tank. This method, although simple, cheap and available often contaminates the water over time. The Project Team of this report recommend the installation of a simple rope pump in the top of the tank roof. Details on the construction of a typical rope pump can be found in [48-51]. The original design also doesn’t include an overflow pipe for when the tank reaches its full capacity. The authors recommend installation of a simple overflow pipe constructed from whatever is available and installed just below the top of the wall scaffolding. The tarp would be arranged so as to direct water through this overflow pipe. The tank design will not be suitable for all soil types and therefore not suitable for all low income RWH situations. Soils with low percentage of clay will not hold enough moisture for the slurry wall to bind to itself. The result is a very low inter-particle stress tolerance and the failure of the organic wall used to house the tarpaulin. The Project Team recommend that the soil be the determining factor when considering the construction of a tarp tank. The galvanised tin roof used in this design may be highly costly in low income countries. The Project Team recommend replacement of the galvanised tin by a thatched, organic roof or similar readily available roofing materials. This does little to affect the quality of the water supply as the water stored in the tank is not typically from the roof of the tank itself, but from another source.

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CP-CBU-125 E3 - Pumpkin Tank An adaption by the Project Team, University of Melbourne, of the Pumpkin Tank design (1995-1998). All images and reference material was sourced from [66]. Size Water volume 5m3 Main Costs Ferrocement, Chicken wire, Anchor bolts, Sand, Mould Construction 1. Prepare ten skeleton / framework legs as shown in Figure E3.1. Prepare the crown ring. This can be used again for many tanks.

Figure E3.1: The framework legs 2. Lay the concrete base using two layers of chicken wire as reinforcing. Allow 300mm of chicken wire to protrude all around the edge of the base. This will be connected to the wall mesh later. Lay 10 anchor bolts for the legs in the base while casting (the diameter will depend on the diameter of the holes in the legs). 3. Leave the base for 7 days to cure, wetting each day. 4. Secure the 10 skeleton legs using the bolts and the crown ring. 5. Take 6mm steel rod and wrap it around the outside of the legs, starting at the bottom and working up at 10cm intervals. CP-CBU-125

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CP-CBU-125 6. Fix 2 layers of chicken wire over the outside of the skeleton. The filter tower can be added at this point if a filter is to be fitted. 7. Plaster the outside of the mesh. Leave for 1 day.

Figure E3.2: Plastering outside of mesh 8. Go inside the tank and remove the skeleton. 9. Plaster inside the tank and cure for 7 days. Water proofing can be added to the mortar. This can be a specialist additive or liquid dishwashing soap. Cure the tank by wetting for 7 – 10 days. Fill the gradually starting on day 7, filling at a rate of approximately 300mm per day.

Figure E3.3: Plastering outside of mesh

Figure E3.4: Finished Pumpkin Tank

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CP-CBU-125 E4 - Semi-Submerged Dome Tank An adaption by the Project Team, University of Melbourne, of the Semi-Submerged Dome Tank design (1997). All images and reference material was sourced from [66]. Size Water volume 5m3 Main Costs Cement, Sand, Brick, Labour Construction 1. Find suitable site 2. Dig pit 0.5m larger than the tank diameter Plant an iron rod in the centre of the pit, making sure it is vertical. 3. Construct concrete base.

Figure E4.1: Constructing the concrete base 4. Plant an iron rod in the centre of the pit, making sure it is vertical. 5. Start constructing walls using wire from iron rod to maintain the radius. 6. Once walls are complete backfill the gap between wall and pit with sand. 7. Make concrete ring beam to the shape shown. No reinforcing is required. Fit overflow pipe at this point if required. 8. Prepare two wooden sticks – one end an ‘L’ shape and the other a ‘V’ shape. The length of the stick is 2/3 that of the internal diameter of the tank.1 9. Keeping the ‘L’ shaped end of the stick to top of the tank wall, place the ‘V’ end against the iron rod and wrap string or wire around the rod to support the stick. 10. Start to build the dome shaped roof of the tank with dry bricks. 11. To start, stick the first brick to the lintel with mortar and support it with the first stick. CP-CBU-125

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Figure E4.2: Building the brick dome 12. For the second brick, stick this to the lintel and the first brick and support it with the second stick. 13. Push the third brick into place (with mortar) next to the second brick and move the second stick to hold the third brick. 14. Continue the process as with brick 3 until the first course is almost complete. 15. The final ‘key’ brick should be shaped to fit tightly allowing for the mortar. 16. Remove the sticks once the first course is complete. 17. Continue in this fashion for the subsequent courses. 18. The dome mouth is constructed in a similar way, but using the bricks length-ways. 19. Plaster the outside of the dome, then plaster the inside of the dome. 20. Plaster the inside of the tank. 21. Plaster the floor o the tank 22. Cure the tank by wetting for 7 – 10 days. Fill the gradually starting on day 7, filling at a rate of approximately 300mm per day.

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CP-CBU-125 E5 Single Skin Externally Reinforced Tank An adaption by the Project Team, University of Melbourne, of the Single Skin Externally Reinforced Tank design. All images and reference material was sourced from [66]. Size Water volume 5m3 Main Costs Cement, Sand, Brick, Labour Construction

Figure E5.1: Sketch (not to scale) of the SSER tank, showing the main components

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CP-CBU-125 Find a suitable location for the tank i.e. close enough to the catchment area to conveniently transport the water, an area with suitably firm ground with no risk of subsidence, etc. If the ground is sloping slightly take advantage of this to site overflow pipe later. If the ground is flat the base may have to be laid above ground level to allow overflow water to run off. If the latter is the case, some form of shuttering will be required (bricks can be used and reclaimed for use in the wall later). Assuming there is sufficient slope to take the overflow pipe out as required, dig a circular hole to a depth of 250mm and to a diameter that is two metres plus twice the width of the brick being used and then add 50mm (0.05m) (see note below). Diameter of base = 2.0 + (2 x y) + 0.05 metres where

2.0m is the internal diameter of the tank y is the width of the brick being used 0.05m gives a 25mm border around the base

Figure E5.2: Details of the tank base The footings are then dug to a further 100mm depth. The width of the footings again depends upon the width of the brick being used ñ allow for the 25mm border around the tank, add 50mm inside the tank wall and also make an allowance for the stone that will make up the under-base. Lay the stone to a depth of 150mm. The overflow pipe is now placed such that it will sit partially in the stone (one third of its depth) and partly buried in the concrete (two thirds of its depth). There should be a very slight gradient on the pipe. The elbow is at the centre of the tank. Make a good seal between the elbow and the pipe. Then peg out the area ready for the concrete. A peg is placed at the centre of the tank, next to the elbow. Pegs are then placed at regular intervals around the perimeter of the tank at the same level. Make the base in one session. Use concrete of mix 4:2:1 (aggregate: sand: cement). Level using a tamping board using the pegs as a guide. CP-CBU-125 282

CP-CBU-125 Building the tank wall Material requirement:   

bricks 800 (using brick dimensions shown) Cement 3 x 50 kg bags Sand 1 tonne

Time required: skilled 1.5 days unskilled 1.5 days

Figure E5.3: Brick dimensions used on prototype The tank wall is built simply by forming whole bricks into a circle. The bricks are not cut to shape. This leaves a slight angle between bricks but this causes no problems and is compensated for when rendering. The verticality and cylindricality of the wall can be maintained in one of two ways: 1. By using a spirit level ñ if the wall is set up at the base to be round and the walls are kept vertical then the tank will be perfectly cylindrical. 2. By placing a length of pipe in the elbow and bracing it in the vertical position. A length of is then loosely tied around the pipe and measured to give the desired length. This is then used as a guide for the tank construction.

Figure E5.4: Forming bricks into circle Note: if the first method is used the elbow should be protected to prevent mortar falling in during construction. CP-CBU-125

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CP-CBU-125 The wall is built up to the required height i.e. 2 metres and a trestle ladder is used to pass mortar into the tank for building. Working from the inside is easiest ñ stock up enough bricks inside to finish the wall at an early stage. The wall should then be properly cured by covering the whole with polythene sheet for 7 days and wetting the walls daily. Applying the steel packaging strap Kimarakwija ñ you will have to source a supply of packaging strap and purchase a tensioning tool and crimping tool from Kampala. Quote for the cost of the trip to Kampala, as well as the tool and crimps, in your tender. The full kit for this includes: - steel strapping (comes in rolls of several hundred metres) - tensioning tool (for pulling the strap tight around the tank) - crimping tool (for crimping the strapping once in place) - dispenser (optional tool for easily dispensing the strap ñ makes this job a lot easier) - crimps (usually in a box of 1000 ñ for crimping the strap) Time requirement:  

skilled 0.5 days unskilled 0.5 days

The strap is applied to the brick masonry specimen using a manually operated tensioning tool. Once fully tensioned the strap is crimped using specially designed crimps and crimping tool and then the tensioning tool is removed. It can be seen from Figure E5.5 below that the tensioning tool holds the strap away from the wall in order to allow access for the jaws of the crimping tool. When the tensioning tool is removed there is some loss of tension in the strap and so packing is placed under the strapping (pieces of broken stone can be used) before the tool is removed to prevent this loss of tension.

Figure E5.5: Showing tensioning and crimping arrangement for steel strapping a/ during the tensioning and crimping process b/ when crimping is complete and the tensioning tool has been removed and tension reduced c/ maintaining tension by using packing CP-CBU-125 284

CP-CBU-125 The strapping is placed on every course of bricks for the lower one metre of the tank and then every other course for the upper metre. There can be some difficulty in applying the strapping on the lower two courses because of the difficulty of access for the tool. This can be overcome by digging a small hole in the ground where the tool access is required. This can be filled later. Covering the tank The tank is covered with a thin shell ferrocement cover. This is mortared into place. (this has been quoted for separately) Rendering the tank Material requirement:    

Cement 2 x 50 kg bags Sand 400kg (mix 4:1) Mortar plasticiser 1 litre (where available) Water as required

Time:  

Skilled 1.5 days Unskilled 1.5 days

The tank is rendered both internally and externally to a thickness of 10mm (which varies due to the uneven surface caused by the angled bricks). A 5cm fillet is built up between the wall / base junction. The mix is 4:1 (sand:cement). The internal surface is then painted with a cement slurry. Other (with detail to follow)   

A filter can be placed in the tank cover. This can be the usual bucket of gravel. A 2.5 metre length of pipe is required to run from the elbow in the base to the cover. This is slotted at 2m height to act as the the overflow (more detail to follow). Tap and galvanised pipe ñ I havenít yet given any information about the siting of the tap and the dugout for tap stand. Please make an estimate for this in the quotation. More information will follow

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Figure E5.6: Strap dispenser

Figure E5.7: Strap showing crimps 9

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Figure E5.8: Tank with straps in place (note the double thickness at the bottom ñ we do not want this any longer). The straps are painted with red oxide paint in this photo to prevent rusting as the tank will sit without render for some time during the testing phase. Making the dome cover Step 1 - Making the ‘template’ for shaping the dome. The shape of the mortar dome comes from the shape of the mound of earth it is built on. We therefore need a template to accurately form that mound of earth. Before building the first tank it is necessary to cut this wooden template. Once made, the template becomes a tool that can be used for many more tanks. The template must be the right shape and also strong enough to carry around and use without getting broken. It therefore consists of a piece of plywood, or thin planks, cut to that shape and stiffened by strips of thicker wood. The right shape for the dome is approximately a upwards ‘catenary’. A downwards catenary is the shape taken by a chain hanging between two nails on a wall, so we mark the template out using such a chain (e.g. 1 or 2 lengths of bicycle chain) and then turn it upside down. First cut the plywood so that it measures 125 cm by 100 cm and has square corners. Figure E5.10 shows 2 nails spaced 2.2 meters apart on a horizontal line drawn across a flat wall using a spirit level. Draw a vertical line down the wall from midway between these two nails and mark a short line (the ‘mark’) across it 80 cm below the horizontal line. Hang a light chain between the two outside nails and adjust its length until it just reaches down to this mark. (If you do not have enough chain to do this, see the alternative below.) Slide the thin plywood behind the chain without touching it, so that the long top of the plywood touches the left-hand nail and the right side of the plywood lies along the vertical line. With a pen, copy the shape of the hanging chain onto the plywood, remove the plywood from the wall and saw along the line you have just marked. (Using planks instead of plywood, first nail them rigidly to their stiffening bar so that they can be placed behind the hanging chain; then continue as for plywood). Although it is easiest to make the catenary with two bicycle chains joined end to end, it can also be done with only one. This has to be hung so that it forms just over half the CP-CBU-125

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CP-CBU-125 full U-shaped catenary: one end of the chain is attached to the left-hand nail, the other end is held low and pulled until the lowest point of the chain falls exactly over the ‘mark’. You can now drive in another nail (‘alternative nail position’ in Figure E5.9) to attach the chain to, while you are copying the chain’s shape onto the plywood. It is necessary that the chain has no twists and that it hangs freely, otherwise it might take up the wrong shape. The right shape ensures that the mortar dome is strong (by being everywhere ‘in compression’). Rope is not usually suitable instead of chain, because most ropes twist and are not heavy enough to hang properly. To finish the template, stiffen it with good wooden strips. Now turn the template over so that the long straight side is on top and write the word ‘TOP’ next to it. Smooth the sharp corners to make it safer to carry.

Figure E5.9 Making the template

Figure E5.10: Forming the earth mound

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CP-CBU-125 Step 2 Marking out and making the trench and earth mound. The centre of the cover should be marked by a firm and vertical (use a spirit level) thin stake. Make a clear ink mark or cut a ring round the stake about 30 cm above the ground. Using a string 110 cm long looped once round the stake, mark out a circle of diameter 220 cm on the ground. This circle marks the inside edge of the trench in which the ring beam will be cast. Dig a narrow trench (one hoe’s width) outside this circle and throw some of the soil into the centre round the pole. The idea is to dig down 50 cm leaving a mound of firm soil inside the ring rising up to the ring round the stake. The shape can constantly be checked using the template - now with ‘TOP’ at the top - placed against the stake and rotated like a scraper. The template should be kept level by means of a spirit level and at the right height with its lower corner touching the ring marked on the stake. This is shown in Figure E5.10. If the mound is rough or loose or fissured by drying, it can be plastered with more mud and wooden ‘floated’ to make it smooth and firm. Chicken mesh can be fixed in the trench so that later on it can be used to improve the joint between the mortar lining the tank wall and the mortar of the ring beam. Make a single strip of mesh by cutting a 1.5 meter length into 5 strips each about 18 cm wide and twist joining them end to end - the final strip should be adjusted to fit round the inside face of the trench like a ring. This ring should now be folded longwise into the veeshape shown in Figure E5.11 and the inside half buried in the earth of the dome. To do this you will have to cut out some earth from the inside of the trench, place the chicken mesh then plaster back the earth again. The trench is now too wide for the ring beam, so fill back a step 10 cm high round its outside so that its bottom becomes only as wide as your foot - about 10 cm. (You will need to walk round this slot when you are plastering the dome). This too is shown in Figure E5.12. The bottom of the earth dome that faces into the trench should be grooved with a trowel or stick: these grooves will be ‘copied’ onto the inner edge of the ring beam and will later help ‘key’ the plaster joint to be formed there. Finally place the bucket and the basin on the dome as shown in Figure E5.12. The bucket (the inlet) should be on the side nearest the house, with its edge touching the stake. The large basin (for the excavation access and later the pump hole) should be on the other side of the stake and with its edge 25 cm from the stake. Weight down the bucket and basin with stones and push them into the soil mound so that they do not rock; local excavation will allow the bucket to be sunk a desirable 20 cm into the soil. Put a small fillet of mud round each bowl as shown. Pull out the stake without disturbing the mound. Step 3 Preparing the reinforcing bars Use 6 mm bar; it does not matter whether it is round or knobbly. Make a ring whose diameter is 230 cm, folding over and linking the ends and hammered the link tight so that there is no play in the joint. This ring will take about 8 meters of bar. Test that the ring will sit in the middle of trench without getting close to either its inner or outer edge. Make two further such rings but much smaller, one each for the bucket and the bowl. Each ring should have a diameter bigger than its bucket/bowl so as to leave a clearance of 3 cm all round it where it enters the soil dome.

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CP-CBU-125 Step 4 Casting the ring beam and the pierced dome. The dome and the ring beam that forms its bottom edge are made of strong mortar in the manner shown in Figure E5.13. The mix is 1:3 (cement : sand) and 2 bags of cement should be ample. Concrete, mixed 1:4:2 (cement : sand : small sharp aggregate), is an alternative where such aggregate is available or can be made; a concrete dome needs only 1.5 bags of cement. (Concrete is more difficult to place as a plaster than is mortar and the surface finish achievable is not so good.) The ring beam is about 10 cm x 10 cm, while the rest of the dome is covered with 2 cm of mortar. However round the bucket and bowl this depth is increased locally to about 8 cm to make a good lip to hold the bucket/bowl and to cover the reinforcing rings there. As usual all three rings of reinforcing bar must be in the middle of the mortar with several centimetres of cover on all sides. So they must be placed as the mortaring progresses. The big ring, in the ring beam, is therefore placed only after 5 cm of mortar is already in the trench. It is important to check the mortar thickness nowhere gets less than 2 cm as you work up the dome. There should be no joints in the mortar: the whole dome and ring beam should be made (plastered) in a single session with a mix that is dry enough not to slump. As the soil dome may suck water out of the mortar or concrete applied on top of it, it should be thoroughly wetted before plastering the dome starts. Moreover in a hot climate it is wise to do this plastering early in the day so that the new dome can be covered with wet straw before the sun gets very hot. Step 5 Curing the dome. As soon as the mortar is firm, gently remove the bucket and basin from the top of the dome. Once the dome is cast it needs to cure under moist conditions for 14 days to develop a high strength. The simplest way to ensure it is kept moist is to cover it with plenty of grass and douse this with a jerrycan of water every morning and afternoon.

Figure E5.11: Details of trench (mesh is optional)

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Figure E5.12: Basin and bucket on mound

Figure E5.13: Completed dome

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CP-CBU-125 E6 Large Partially Below Ground Tank An adaption by the Project Team, University of Melbourne, of the Large Partially Bellow Ground Tank design (1997). All images and reference material was sourced from [66].

Figure E6.1: Large Partially Below Ground Tank

Size Water volume up to 10.8m3 Main Costs Cement, Sand, Brick, Labour

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CP-CBU-125 Construction 1. Finding a suitable site 1.1. The first step is to find a suitable site for the tank. Some pointers for what constitutes a good site are given below:  Close enough to the dwelling to avoid long lengths of guttering and downpipe (some suggest siting the tank mid way along the length of a building to reduce gutter size– this is fine if water from one side of the building only will be fed into the tank)  Reasonably flat where possible – otherwise the ground will have to be levelled before marking out  Away from areas where surface water will gather (i.e. depressions)  Away from trees – the roots of trees can be problematic  Away from areas where animals will wander – or else the tank should be fenced off  Not so close to the dwelling that the foundations of the dwelling are undermined  Somewhere convenient for extracting water e.g. close to the kitchen area 1.2. The ground should be suitable for digging and for siting such a tank. There should be no large stones, bed rock or sheet rock close to the surface, and one should be sure that the groundwater table in the area is several meters below the bottom of the tank. This information can often be gleaned from locals who may have tried digging wells, sinking boreholes or digging garbage pits.

Figure E6.2 - Showing the cleared ground and the markings in place for the ring beam 2. Deciding what depth the tank will be 2.1. As mentioned earlier, the sizing of the tank in terms of supply and demand is not given in this document. It is assumed that the sizing of the tank has been carried out correctly. 2.2. The nominal diameter of the tank is given as 2m. All the sizes given in these instructions are for a tank of 2m nominal diameter. The actual internal diameter is slightly less than this. 2.3. The actual volume of the tank is dependant, therefore, upon the depth of the tank. Table 2 below shows the volume of the tank for a number of given depths (the depth is total depth from the top of the parapet wall, which is 1.0m high).

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Table E6.1: Depths and Volumes for PBG Tank

3. Casting the ring beam 3.1. Mark out two circles with inner and outer diameters of 1.9 and 2.2m respectively (i.e. radii of 0.95 and 1.10m respectively). This gives a ring beam of width 0.15m (150mm) 3.2. Dig between the lines to a depth of 150mm keeping the trench neatly trimmed and clean. A machete can be used for trimming the walls of the trench to get a good, clean finish. When completed clean out any loose earth from the trench.

Figure E6.3: Casting the ring beam 3.3. Make a concrete mix of 1:2:4 (cement : sand : aggregate), using the quantities shown in Table 5. Be sure the concrete is well mixed and then place the mix into the trench being sure that any air voids are removed by ‘vibrating’ the concrete with a stick. Remember that wet concrete mixes will have lower final strength, so keep the mix workable but not too wet.

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CP-CBU-125 Table E6.2: Quantity of material required for the ring beam

3.4. The ring beam should be covered and cured for 7 days before any further work is carried out (keep the concrete wet during the curing period). Keep the beam covered with polythene during this time and wet the concrete at least twice a day.

Figure E6.4: Dimensions for marking for the ring beam 4. Excavating the hole 4.1. When the beam has cured the hole can be dug. Use Table 4 to decide what depth of hole is required. The sides of the tank should be kept reasonably vertical. This can be checked occasionally using a plumb line or a masons spirit level. 4.2. As a rough estimate of the time and manpower required to dig the hole, use the value of 1 person-day per cubic metre of excavation. 4.3. The bottom of the hole is shaped like a hemisphere or an inverted dome. This shape is easily dug with a shovel. A rod can be placed centrally in the ground and a piece of string used as a guide if there is any difficulty.

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Figure E6.5: Excavation of the tank

Figure E6.6: Plumbing the walls to keep them vertical

5. Building the parapet wall 5.1. The parapet wall is built to a height of 1.0m. It is recommended that bricks be cast and fired especially for the construction of the tank to the dimensions shown in Figures E6.7 and E6.8 below. Where this is not possible, it is recommended that a standard 100 x 75 x 225 fired house-brick is used, although other (larger) sizes can also be used.

Figure E6.7: Showing the mould used for casting the bricks used for the parapet wall CP-CBU-125

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Figure E6.8: The bricks with profiled ends 5.2. The number of bricks required depends on the actual brick size, but assuming the dimensions are as given above, then 24 bricks per course will be required. For a height of 1.0m this will be a total of 240 to 270 bricks (10 or 11 courses depending on thickness of mortar used). This represents 6m2 of brickwork. 5.3. Bricks should be laid with a mortar mix of 1:6. When placing the final course of bricks two small gaps should be left, one for handpump pipe, which will be placed later, and the other for the overflow pipe. This should also be cast into the wall at this stage. 5.4. The overflow trap (see Figure E6.9) allows overflow water to escape from the tank while preventing mosquitoes from entering the tank. The U-trap is filled with water and so mosquitoes cannot pass. A mosquito mesh also prevents mosquitoes entering the overflow pipe. The trap is made from 50mm (or similar) plastic pipe. If the U-trap is not used then mosquito mesh should be fitted over the end of the overflow pipe. The tank owner should be advised to replace this if damaged or removed. 5.5. When complete, the parapet wall can be externally rendered. This is not essential but makes the tank look better.

Figure E6.9: a/ where bricks are cast and fired specially for tank construction, they can be cast with a slight angle at each end. To minimise the amount of mortar used the bricks should be cast with an angle of 7.5 degrees on each end of the brick b/ showing actual dimensions of brick cast for tank construction

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CP-CBU-125 Table E6.3: Quantity of material required for the parapet wall

5.7. Allow 2 skilled person-days and 2 unskilled person-days for building and rendering the parapet wall.

Figure E6.10: Showing the construction of the parapet wall 6. Lining and water-proofing the tank 6.1. Any sharp stones or roots protruding from the wall should be removed. Where holes have prepared due to stones having been removed, these should be filled with clay soil and tamped hard and level with the surrounding surface. 6.2. It is very important to achieve a waterproof lining for the tank. As mentioned earlier, one of the rawbacks of an underground tank is that it is difficult to

6.3. Ferro-cement render. This technique is based on the well-known ferrocement technology that has been well documented (see Watt, 1978 and Gould and Nissen Peterson, 1999). The technique involves using a composite of cement render and galvanised chicken wire mesh. A water-proofing compound (readily available in most countries) is added to the cement render. The procedure for application is given here:  A thin coat (~ 1cm) of 3:1 cement render is applied evenly to the wall of the tank. When the render has started to set (after about 30 minutes), score the render lightly to provide a key for the next layer.  This first coat is allowed to cure for 2 days. The top of the tank should be covered with a plastic sheet during this time and the walls regularly and liberally sprinkled with water.

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Figure E6.11: - Showing the rendering in progress  



A layer of 1” chicken wire mesh is then applied to the render. This mesh is fixed to the render using galvanised fencing staples. Care should be taken to lay the mesh as flat as possible onto the render. When the chicken wire is in place the second coat of render can be applied. This is again a 1:3 mix, but includes a waterproofing agent, which is added during the mixing. Any proprietary waterproofing agent can be used and the manufacturer's instructions followed regarding the quantity to be added. The second coat of render should be applied in a similar fashion to the first – about 1cm in thickness (although it may be thicker in places to cover the chicken mesh). This second coat of render should be cured for 7 days as described above. The gap around the overflow pipe should be sealed using a waterproof mortar. This is done before the cover is fitted. Scaffolding or ladders should be used when rendering the walls of the tank. See Figure E6.12

Scaffolding or ladders should be used when rendering the walls of the tank.

Figure E6.12: Ladders and boards used to provide a working platform Material requirement for render: 7. Fitting the handpump 7.1. More detail of the handpump is given in another DTU publication – TRRWH 09 “Lowcost handpumps for water extraction from below-ground water tanks - Instructions for Manufacture”. The fitting and fixing procedures are dependant on the type of pump used. CP-CBU-125

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CP-CBU-125 8. Making and fitting the cover. 8.1. The manufacture of the cover is discussed in a separate document TR-RWH 04 " Lowcost, thin-shell, ferrocement tank cover - Instruction for Manufacture". The cover is made independently of the tank and is fitted when complete.

Figure E6.13: The tank with cover in place 8.2. The cover is easily lifted into place by 4 – 6 people. It weighs in the region of 200kg and the lifting height is 1m. Care should be taken when lifting the cover and proper safety precautions should be observed. 8.3. The cover will be mortared into place. A 2cm thick mortar is placed on top of the parapet wall and the cover is placed onto the mortar. The mortar is smoothed to seal the cover onto the wall. The mortar is also smoothed on the inside of the wall / cover joint to form a continuous waterproof lining. 9. The filter is part of the cover. When the cover is manufactured, a plastic basin is used to form the access opening. This basin is then left in place, filled with coarse gravel and covered with a fine cloth. The cloth filters out any coarse debris and should cleaned when dirty and replaced when damaged. It is easy to monitor the condition of the cloth as it is in clear view on top of the tank. The owner of the tank should be made aware of this.

Figure E6.14: Showing two types of handpump (DTU and Tamana), filter basin and externally rendered parapet wall, on this demonstration tank at Kyera Farm, Mbarara, Uganda. The guttering has not yet been fitted. CP-CBU-125 300

CP-CBU-125 10. Guttering and pipework 10.1. The guttering and downpipe are not specified. This is due to the wide variation in the styles available. This is left to the discretion of the installer. 10.2. In the general diagram in Figure E6.1, a low-level inlet is shown. This helps to prevent disturbance of the water and directs sediment to the bottom of the tank. The floating intake then takes water from just below the water's surface, where is cleanest. This arrangement is not essential but it is desirable, especially where the water is used for potable supply. The fitting of the lowlevel inlet again is left to the discretion of the installer. The floating intake is discussed in TR-RWH 09.

11. Maintenance. The maintenance of the tank is quite simple. The following steps should be followed:  The tank should be cleaned annually - at the end of the dry season, the tank should be emptied and any debris in the bottom of the tank removed.  The filter should monitored to make sure that it does not become blocked. If the cloth becomes damaged it should be replaced.  The overflow should be covered with mosquito mesh at all times.  The tank and associated guttering and pipework should be kept in good general repair. Any damage or faults should be rectified as soon as possible.  The maintenance of the pump is discussed in TR-RWH 09.

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Appendix F - Gantt and Project Charts F1 Gantt Chart for Scope of Works Submission

CP-CBU-125 F2 Gantt Chart for Progress Report 1 Submission

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F3 Gantt Chart for Progress Report 2 Submission

CP-CBU-125 F4 Project Scope Flow Diagram

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CP-CBU-125 F5 Changes to Gantt Chart Since Progress Report One

Table F5.1: Summarises which tasks from PR1 has been completed, which tasks have been added and which tasks have been deleted. TASKS General

Completed Progress Emails To EWB and Colin Dreamlarge Grant Successfully Attained In Country Research Background Research Current System Research

First Flush

First Flush research Design: Idea Forming Construct Prototypes Test Prototypes Education Construct RWH Model Literature Review

Tanks

Model Rainwater Data

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Deleted

First Flush Experiments Cambodia Cost Analysis

First Flush Report

Determine Scope Meet With Industry Expert Pamphlet Translated Organise Visits To Schools Survey School Children Build RWH Model Survey Locals Build Alternative Tank in Melbourne Build Alternative Tank in Cambodia Tank Cost Analysis True Cambodia Cost Analysis Source and Cost Hydrophilic Seals

Education Report

Optimisation Report

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Appendix G - Meeting Minutes

Meeting Minutes MCEN90022 Capstone Project Year Long Project

Meeting Minutes Date: 09/11/2011 Duration: 1 hour A.1 Present Jack, Zac, Grace, Dave

A.2 Regrets

A.3 Follow up from last meeting

A.4 Schedule/Important Upcoming Dates

A.5 Tasks Completed Formation of team for Capstone project Initial contact over email to Colin re EWB project

A.6 Actions going forward Speak to Colin directly and apply for EWB project through unimelb channels Liaise with Julian O’Shea at EWB regarding projects available

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CP-CBU-125 Meeting Minutes Date: 12/11/2011 Duration: 1 hours A.1 Present All

A.2 Regrets None

A.3 Follow up from last meeting Colin interested in us doing project, need to email project selection form and meet him to discuss

A.4 Schedule/Important Upcoming Dates 21 Nov, EWB projects decided

A.5 Tasks Completed Application document for University of Melbourne

A.6 Actions going forward Secure project at EWB end Meet Colin to secure project

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CP-CBU-125 Meeting Minutes - Meet Colin to secure EWB project Date: 15/11/2011 Duration: 0.5 hours A.1 Present All, Colin Burvill

A.2 Regrets

A.3 Follow up from last meeting Meet Colin

A.4 Schedule/Important Upcoming Dates 21 Nov, EWB projects decided

A.5 Tasks Completed Awarded project from University of Melbourne after meeting with Colin

A.6 Actions going forward Sort out Dave’s sem2 enrollment to year long “officially” Secure project on EWB end

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Meeting Minutes Date: 23/11/2011 Duration: 1 hour A.1 Present All

A.2 Regrets None

A.3 Follow up from last meeting Secure project through EWB - success Daves enrollment - done

A.4 Schedule/Important Upcoming Dates

A.5 Tasks Completed Secure EWB “Designing the ultimate Maintenance free rainwater harvesting system” project

A.6 Actions going forward Arrange to meet up with James whilst over in Cambodia - Jack, Grace and Zac Begin contextual understanding and research over summer break

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Meeting Minutes Date: Feb 4th, 2012 Duration: 2 hours A.1 Present All, via skype and phone

A.2 Regrets

A.3 Follow up from last meeting Grace to meet up with James in Cambodia Jack and Zac unsuccessful in meeting up with James due to time and date constraints

A.4 Schedule/Important Upcoming Dates

A.5 Tasks Completed Initial ideas of scope of project

A.6 Actions going forward Paperwork for EWB Grace to meet up with James in Cambodia

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Meeting Minutes - First meeting after start of sem 1 Date: 28/02/2012 Duration: 3 hours A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Grace to meet up with James in Cambodia - done Paperwork for EWB - complete

A.4 Schedule/Important Upcoming Dates Mon 19th March - IA

A.5 Tasks Completed Grace to meet up with James in Cambodia: Resulted in photos and large amount of background context which was passed onto group during the meeting Set up regular meeting time, Tuesdays at 12 - tentative at this stage More initial project direction ideas

A.6 Actions going forward Begin Brainstorming Plan out scope of project, IA Gantt Chart CP-CBU-125 312

CP-CBU-125 Begin Scope of Works document submission Complete all paperwork for School of Eng Complete all remaining paperwork for EWB

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Meeting Minutes - Gantt chart session Date: 06/03/2012 Duration: 3 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Begin Brainstorming - in progress Plan out scope of project, IA - in progress Gantt Chart - do in session Begin Scope of Works document submission - in progress Complete all paperwork for School of Eng - done Complete all remaining paperwork for EWB - done

A.4 Schedule/Important Upcoming Dates Mon 19th March - IA Sat 12th May - Speaker presentation at Humanitarian Research Forum

A.5 Tasks Completed Gantt Chart, including all defined subtasks Regular meeting time set - Tues 12

A.6 Actions going forward All members to begin research into first flush CP-CBU-125 314

CP-CBU-125 Brainstorming of ideas Scope of Works document submission

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CP-CBU-125 Meeting Minutes Date: 13/03/2012 Duration: 1 hour A.1 Present Zac, Grace, David

A.2 Regrets Jack - away at unrelated EWB program

A.3 Follow up from last meeting All members to begin research into WASH - some progress Brainstorming of ideas - progress Scope of Works document submission

A.4 Schedule/Important Upcoming Dates Mon 19th March - IA Sat 12th May - Speaker presentation at Humanitarian Research Forum

A.5 Tasks Completed Scope of Works draft - submitted to Colin for improvements

A.6 Actions going forward Act on Colin’s comments on Scope document Submit final Scope document before Mon 12:00 Once complete, begin extensive literature review

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CP-CBU-125 Meeting Minutes Date: 20/03/2012 Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Act on Colin’s comments on Scope document - complete Submit final Scope document before Mon 12:00 - complete Once complete, begin extensive literature review - begun

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed Scope of Works submission

A.6 Actions going forward Literature Review - all New first flush designs

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CP-CBU-125 Meeting Minutes Date: 27/03/2012 Duration: 1 A.1 Present Grace, Jack, Dave

A.2 Regrets Zac

A.3 Follow up from last meeting Literature Review - in progress New first flush designs - in progress

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed All review and design tasks on track

A.6 Actions going forward Meet with dreamlarge grant people Get James Oakleys feedback on initial designs and research

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Meeting Minutes - Dreamlarge grant Date: 30/03/2012 Duration: 1 hour A.1 Present Zac, Partnership office staff

A.2 Regrets None

A.3 Follow up from last meeting Meet with dreamlarge grant people

A.4 Schedule/Important Upcoming Dates

A.5 Tasks Completed Meet with dreamlarge grant people - Zac, very good case for grant. Need to complete ASAP and attend information session. Then liase with Dream large people about feedback on grant proposal. Do so early.

A.6 Actions going forward Zac - prepare dreamlarge grant

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Meeting Minutes Date: 03/04/2012 Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Literature Review - largely complete New first flush designs - current designs largely complete, now focus on new designs Contact James - feedback on initial designs and research - done and responded with comments, see dropbox. Further comments provided by Colin. Outcome - good progress with FF, James comments confusing???

A.4 Schedule/Important Upcoming Dates 6th April - Brainstorm session at PA’s Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed Basic background/context review mostly complete FF designs research complete - 4 design types identified, few random ones

25A.6 Actions going forward

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CP-CBU-125 ALL - CONTACT JAMES REGARDING SCOPE OF PROJECT. James comments seem to indicate we should be looking at the entire RWH system. Priority #1 is now to contact James in regard to FF issue Zac - prepare dreamlarge grant All - bring initial ideas to PA’s brainstorm session

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CP-CBU-125 Meeting Minutes - PA’s brainstorm session Date: 06/04/2012 Duration: 3 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting All - bring initial ideas to PA’s brainstorm session

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed Brainstorm, clarify and select 2 promising FF designs

A.6 Actions going forward All - Refine design ideas, further designing, move towards building one or two design All - Look into existing patent websites Keep trying to contact James regarding scope issue

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CP-CBU-125 Meeting Minutes Date: 17/04/2012,After Mid sem break 6th to 15th April Duration: 1 hour A.1 Present Jack, Dave, Zac

A.2 Regrets Grace

A.3 Follow up from last meeting All - Refine design ideas, further designing, move towards building one or two design complete All - Look into existing patent websites - complete Keep trying to contact James regarding scope issue - still no word back

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed Overall review of progress, directions and thoughts Looking at gantt chart to gauge progress

A.6 Actions going forward Contacting James - Spoke to Colin, who suggested contacting Julian O’Shea regarding getting in touch with James

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CP-CBU-125 Meeting Minutes Date: 24/04/2012, Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Keep trying to contact James regarding scope issue - Calling him at 10am Cambodia time, 2:30 Melb time. Use EWB phone in Elec eng.

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed Overall review of progress, directions and thoughts Looking at gantt chart to gauge progress

A.6 Actions going forward Contacting James - Calling at 2:30, with prepare list of agenda items

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CP-CBU-125 Meeting Minutes - James Skype/Phone Call Date: 24/04/2012 Duration: 1 hour A.1 Present Zac, Jack

A.2 Regrets Grace, Dave

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Skype connection was too poor, had to use landline to call Cambodia. We were able to secure a landline through EWB connections

Discussed with Jame: ● ● ●

New scope of project - to include all aspects of RWH system, inc FF Have to work together as no real definition of works to be completed/problems Identified some issues; 1. FF, 2. Locals cutting open tank for greywater addition 3. leaking tank issue 4. education/awareness issues 5. cost of overall system

●

Has huge amount of research on entire system, background, etc. Is adding us to dropbox account as doesn’t have the space to use ours.

Outcomes ● ●

Complete scope change of project We will need to work closely with James to develop the scope and direction of the project in the next few weeks. NOT simply list of issues to fix, more complicated. CP-CBU-125 325

CP-CBU-125 PRIMARY FOCUS: Read all James’s documentation and begin our own WASH and RWH research. Need a solid literature base before value can be added to this project due to its complex scope. ● Next step would be to look into the specific systems discussed with James, including Jumbo Jars and other tanks, possibly underground piping, leaking concrete tanks, etc ● Simultaneously conduct research into existing systems as per first flush research. ●

A.6 Actions going forward All - read new scope document in dropbox, Jack to prepare All - read James’s documentation All - begin preliminary research into all areas, use references in James stuff as starting points

Meeting Minutes - extra meeting to discuss new scope Date: 25/04/2012 Duration: 3 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed New direction of scope encompasses entire system. Back to square 1, need to review entire existing system - James sending through documents via dropbox James identified issues - discussed as group. Need more info to fully appreciate Discussed focus of literature review Decisions ●

FF to be put on hold until literature review is complete CP-CBU-125 326

CP-CBU-125 ● ● ●

Existing system information is PRIORITY Second priority (while we wait) is research Everyone to work on these aspects for now

A.6 Actions going forward All - read new scope document in dropbox, Jack to prepare All - read James’s documentation when it comes in All - begin preliminary research into all areas, use references in James stuff as starting points Zac, with input from all - prepare new gantt chart (use scope document)

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Meeting Minutes Date: 01/05/2012 Duration: 1 hour A.1 Present Jack, Grace, Zac

A.2 Regrets Dave

A.3 Follow up from last meeting All - read new scope document in dropbox, Jack to prepare - complete All - read James’s documentation - ongoing All - begin preliminary research into all areas, use references in James stuff as starting points ongoing

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1

A.5 Tasks Completed All - read new scope document in dropbox, Jack to prepare - complete Initial review of existing system - a document outlining the parameters of RWC’s current RWH system for domestic installations - sent to James to fill in specifics and check to see we are on the same page - completed and comments received (today)

A.6 Actions going forward All - read James’s documentation CP-CBU-125 328

CP-CBU-125 All - begin preliminary research into all areas, use references in James stuff as starting points Continue to build on existing system doc Prepare slideshow presentation and poster for humanitarian research forum - All

CP-CBU-125 329

CP-CBU-125 Meeting Minutes Date: 08/05/2012 Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting All - read James’s documentation - Jack complete, others ongoing All - begin preliminary research into all areas, use references in James stuff as starting points Continue to build on existing system doc - Zac working on Prepare slideshow presentation and poster for humanitarian research forum - Grace started

A.4 Schedule/Important Upcoming Dates Sat 12th May - Speaker presentation at Humanitarian Research Forum 21st May - Progress Report 1 25th May Dreamlarge Submission

A.5 Tasks Completed Sent Colin outline of FF design, Dave and Zac to draw up designs for PR1

A.6 Actions going forward Zac, Grace , Dave - read James’s documentation All - begin preliminary research into all areas, use references in James stuff as starting points Continue to build on existing system doc Prepare slideshow presentation and poster for humanitarian research forum - All CP-CBU-125 330

CP-CBU-125 Grace - continue working on slideshow, good basis for prog 1 Jack - begin poster layout for Humanitarian conference, send to group and colin by end of today for layout

CP-CBU-125 331

CP-CBU-125 Meeting Minutes - Humanitarian Research Forum Date: 12/05/2012 Duration: 9 hours A.1 Present All at some stage

A.2 Regrets A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed ● ●

Successful presentation of project in 15 minute PPT presentation Networked with researchers, academics and field engineers working on similar projects around the world ● Learned a lot more about Cambodian context from other presentations ● Further understanding of WASH sector ● Further understanding of Humanitarian sector and humanitarian engineering

Outcomes ● ● ●

Successful presentation EWB mentor (Julian O’Shea) delighted Information from 2 contacts regarding Cmabodia (Klyti Scott) and RWH (Jane Nicholls) for potential research base and idea generation ● Potential avenue for guttering-roof ratio optimisation

A.6 Actions going forward Add Jane and Klyti’s material to dropbox and all members to read Follow up on any information gathered - Individual

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CP-CBU-125 Meeting Minutes Date: 15/05/2012 Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Add Jane and Klyti’s material to dropbox and all members to read - done Follow up on any information gathered - Individual - Outcome - explore education aspect further All - read James’s documentation - Jack complete, others ongoing All - continue preliminary research into all areas, use references in James stuff as starting points Continue to build on existing system doc - Zac working on - complete for now - in DB

A.4 Schedule/Important Upcoming Dates 21st May - Progress Report 1 25th May Dreamlarge submission

A.5 Tasks Completed Add Jane and Klyti’s material to dropbox and all members to read - done Follow up on any information gathered - Individual - Outcome - explore education aspect further Decision to focus all energy on PR1 submission write up, this will help identify holes in literature review

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CP-CBU-125 A.6 Actions going forward Zac, Grace , Dave - read James’s documentation All - continue preliminary research into all areas, use references in James stuff as starting points FOCUS - PR1 and associated lit/systems review

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CP-CBU-125 Meeting Minutes Date: 22/05/2012 Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Zac, Grace , Dave - read James’s documentation All - continue preliminary research into all areas, use references in James stuff as starting points FOCUS - PR1 and associated lit/systems review - complete

A.4 Schedule/Important Upcoming Dates 25th May Dreamlarge Submission 28th May SWOT VAC

A.5 Tasks Completed PR1 submission email discussion with James regarding translation of the education pamphlet email discussions with Colin regarding report writing and grant submission Discussion on fact that exams are here and work will probably cease until after exam period, budgeted for in gantt chart Final touches on Dreamlarge submission - Zac, emailed to James and Julian (OK), today emailed to Colin → submit by Friday

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CP-CBU-125 A.6 Actions going forward Exams, not further capstone work until after exams

June 4th to 22nd - Exams (No Capstone work)

22nd June - 23 July - Mid Semester Break. Zac, Grace, Jack away. (No or very little Capstone work)

CP-CBU-125 336

CP-CBU-125 Meeting Minutes - contact with James in holidays Date: 11/06/2012 Duration: 0.5 hours A.1 Present Jack

A.2 Regrets Zac, Grace, Dave

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Email conversation with James regarding progress at current position (holidays) ● ● ●

Sent copy of reports and up to date research discussed direction and scope Discussed James movements (changeover in September)

A.6 Actions going forward Email summary out to all group members Be ready come week 1

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CP-CBU-125 Meeting Minutes Date: 24/07/2012 Duration: 2 hour A.1 Present Jack, Grace, Dave

A.2 Regrets Zac (overseas)

A.3 Follow up from last meeting

A.4 Schedule/Important Upcoming Dates 6th August PR2 due

A.5 Tasks Completed Project direction - to be further completed when Zac returns next week

A.6 Actions going forward Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries

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CP-CBU-125 Meeting Minutes Date: 31/07/2012 Duration: 2 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Need to formalise direction and delegate tasks

A.4 Schedule/Important Upcoming Dates Tues 14th Aug - Progress Report 2 submission and Oral presentation (12:00 to Colin, 4:00 to Andrew)

A.5 Tasks Completed Dreamlarge grant awarded!!!! Zac to follow up on all details, paperwork and red tape issues Project Discussion ●

Project group direction, happy with how scope has evolved to and now ready to deliver on issues ● Need to focus on key areas, otherwise project will continue to expand and we will have no deliverables at the end ● Key focus areas to be allocated amongst group ● Aim to not open up anymore new design routes or new avenues of research

Outcomes ●

division of tasks Grace - Education Dave - FF Tanks - Jack and Zac

CP-CBU-125 339

CP-CBU-125 A.6 Actions going forward Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries Begin formalising direction in each of key focus areas Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE Build RWH test rigs Dave - pursue canvas bag design concept

Meeting Minutes Date: 7/08/2012 Duration: 1 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries - done Begin formalising direction in each of key focus areas - done Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports - ongoing Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE - Been put in touch with Jan May at MSE, zac coordinating

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CP-CBU-125 A.4 Schedule/Important Upcoming Dates Tues 14th Aug - Progress Report 2 submission and Oral presentation (12:00 to Colin, 4:00 to Andrew)

A.5 Tasks Completed Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries - done Begin formalising direction in each of key focus areas - done Got in touch with academic examiner Andrew Wirth, sent progress reports and updates ahead of presentation next week Change of name through Endeavour to accurately reflect new project scope. Now “optimising rainwater harvesting in rural cambodia” RWH test rigs complete and ready for test models canvas bag design concept model complete

A.6 Actions going forward PRIORITY: PR2, need slides for presentation AND PR2 document Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries Begin formalising direction in each of key focus areas Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

Meeting Minutes - Nossal Institute of Global Health Date: 08/08/2012 CP-CBU-125 341

CP-CBU-125 Duration: 1 hour A.1 Present Zac and Grace

A.2 Regrets None

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Prepared a summary of the project, list of questions and concerns, and topics to discuss for the meeting with Associate Professor Jim Black and Naomi.

A.6 Actions going forward Attend meeting on 10/08/2012 at 1pm

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Meeting Minutes - extra meeting to combine slides for presentation Date: 10/08/2012 Duration: 2 hour A.1 Present Zac, Grace, Jack

A.2 Regrets Dave

A.3 Follow up from last meeting PRIORITY: PR2, need slides for presentation AND PR2 document Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries Begin formalising direction in each of key focus areas Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

A.4 Schedule/Important Upcoming Dates Tues 14th Aug - Progress Report 2 submission and Oral presentation (12:00 to Colin, 4:00 to Andrew)

A.5 Tasks Completed Combined slides for presentation - too long. Many slides removed and others consolidated Practise presentation runs for next tues - good by the end

A.6 Actions going forward CP-CBU-125 343

CP-CBU-125 PRIORITY: PR2, need slides for presentation AND PR2 document Draft of powerpoint slides for presentation to be completed by end of day/asap Grace: to confirm with Colin time of presentation and await Andrew Wirth’s reply of availability

Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries Begin formalising direction in each of key focus areas Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

CP-CBU-125 344

CP-CBU-125 Meeting Minutes meeting with Associate Professor Jim Black and PhD student Naomi Date: 10/08/2012 Duration: 1 hr A.1 Present David and Grace A.2 Regrets Jack and Zac

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates 14th Sept - Fly to Cambodia

A.5 Tasks Completed

A.6 Actions going forward Have all documentation ready for Cambodia

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Meeting Minutes - extra meeting to rehearse presentation Date: 14/08/2012 Duration: 2 hour A.1 Present All

A.2 Regrets

A.3 Follow up from last meeting PRIORITY: PR2, need slides for presentation AND PR2 document Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries Begin formalising direction in each of key focus areas Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

A.4 Schedule/Important Upcoming Dates Tues 14th Aug - Progress Report 2 submission and Oral presentation (12:00 to Colin, 4:00 to Andrew)

A.5 Tasks Completed Practise presentation, timing of each speech, adjusting of small errors

A.6 Actions going forward PRIORITY: PR2, need slides for presentation AND PR2 document

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CP-CBU-125 Zac, Grace , Dave - read James’s documentation, also Martinson Thesis on RWH in low income countries Begin formalising direction in each of key focus areas Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

CP-CBU-125 347

CP-CBU-125 Meeting Minutes - PR2 Presentation - Colin Burvill Date: 14/08/2012 Duration: 1 hour A.1 Present All

A.2 Regrets A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Delivered very successful presentation!!! Colins comments after presentation ● ● ● ● ● ● ● ● ● ● ● ● ●

define NGO, improved water sources Add legacy to gantt chart add scoping and partnerships as tasks in report and in gantt add uni logo and dreamlarge logo to presentation turn education meetings into experiments Translate basic education experiments google translate relate available materials to 1st world poly concrete - is this an option (for eg) Don’t stress about needing to build, give details aim for quantitative feedback on ideas poss split report up into infrastructure change, social and education change Don’t say scope adjusted, say obtain common undersatanding - and barriers to this (language, country, dist away, grant ● list of documents in appendix

A.6 Actions going forward Add comments into PR and slides (and Final Report) where possible

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CP-CBU-125 Meeting Minutes - PR2 Presentation - Andrew Wirth Date: 14/08/2012 Duration: 1 hour A.1 Present All

A.2 Regrets A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Again, delivered very successful presentation

No direct comments, many questions

A.6 Actions going forward send Andrew a copy of the report and slides

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CP-CBU-125 Meeting Minutes Date: 16/08/2012 Duration: 1 hour A.1 Present Grace, Zac, Jack

A.2 Regrets Dave

A.3 Follow up from last meeting Need to resubmit PR1 as it is not ‘punchy’ enough.

A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed A.6 Actions going forward Grace - rewrite of education part Jack - add more findings to tank stuff Dave - rewriite of FF Zac - collate all areas and finish report correctly

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CP-CBU-125 Meeting Minutes Date: 21/08/2012 Duration: 1 hr A.1 Present All

A.2 Regrets none

A.3 Follow up from last meeting PR2 - complete and submitted Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

A.4 Schedule/Important Upcoming Dates 14th September - Fly to Cambodia for 2 weeks

A.5 Tasks Completed Progress Education - model built, need fine tuning, pamphlet translated, research continuing and written up Tanks - alternative systems review almost complete and ready for Cambodia, costing sheet complete, tarp tank ready to be built (mat purchased), leak issue still developing documents, rigs ready for testing FF - canvas bag design testing underway, ball valve tests underway, Extension granted for Final Report submission, now have until the 15th October

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CP-CBU-125 A.6 Actions going forward Insurance - Jack to speak to Jan May at MSE 4th floor Flights - everyone to book and add receipts to DB Continue work on key focus areas, now looking to put all into writing for final report and cambodia

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CP-CBU-125 Meeting Minutes Date: 28/08/2012 Duration: 1 hr A.1 Present All A.2 Regrets none

A.3 Follow up from last meeting Begin writing up all findings, designs, scribbles, notes, literature, arguments, etc ready for Cambodia and reports Look into flights, insurance, itinerary, etc - speak to James, Colin, MSE

A.4 Schedule/Important Upcoming Dates 14th September - Fly to Cambodia for 2 weeks 15th Oct Final Report Submission

A.5 Tasks Completed Literature review and final report skeleton complete - Jack James has been in contact and is sending through itinerary next week Progress on alt tank writeup - Zac

A.6 Actions going forward Insurance - Jack to speak to Jan May at MSE 4th floor Flights - everyone to book and add receipts to DB - just grace left Continue work on key focus areas, now looking to put all into writing for final report and cambodia Begin all work that needs to be ready for Cambodia CP-CBU-125 353

CP-CBU-125 Meeting Minutes Date: 28/08/2012 Duration: 2 hours A.1 Present All A.2 Regrets

A.3 Follow up from last meeting Insurance - Jack to speak to Jan May at MSE 4th floor - done Flights - everyone to book and add receipts to DB - done - give to Jan ater project Continue work on key focus areas, now looking to put all into writing for final report and cambodia Begin all work that needs to be ready for Cambodia

A.4 Schedule/Important Upcoming Dates 14th September - Fly to Cambodia for 2 weeks 15th Oct Final Report Submission

A.5 Tasks Completed Insurance - Jack to speak to Jan May at MSE 4th floor - done HR19 forms handed in to Jan - done Final report structure complete - Technical and non-technical Discussed feedback from PR2 Discussed developments of each key focus area Discussed concerns from EWB, RWC of education survey - OUTCOME: Scale back research participant numbers

A.6 Actions going forward CP-CBU-125 354

CP-CBU-125 PRIORITY: Prepare all documents ready for Cambodia Write report intro and literature review Call Terri - EWB field placement coordinator Call James Grace to call Julian Organise predeparture meeting

CP-CBU-125 355

CP-CBU-125 Meeting Minutes - Grace discussion with Julian O’Shea, EWB education Director Date: 28/08/2012 Duration: 0.5 hours A.1 Present Grace A.2 Regrets

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Clarify with Julian the education aspect of the project Clarify what is appropriate for Cambodian context and community

A.6 Actions going forward Modify education program for research whilst in Cambodia

CP-CBU-125 356

CP-CBU-125 Meeting Minutes - Briefing with Terri Maher, EWB Field placement Coordinator, SE Asia Date: 28/08/2012 Duration: 1 hour A.1 Present All A.2 Regrets

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Pre departure checklist runthrough ● ● ● ● ● ●

work visas all paperwork complete risk analysis done DFAT Accommodation - tourist quarter near river Khmer language Pre departure briefing set for MON 2pm

A.6 Actions going forward Pre departure meeting set Call James Email Julian outcomes Book accommodation for first 3 days

CP-CBU-125 357

CP-CBU-125 Meeting Minutes - Discussion with James Oakley Date: 28/08/2012 Duration: 1 hour A.1 Present Zac and Jack

A.2 Regrets Grace and Dave

A.3 Follow up from last meeting Mon 3rd Sept - Predeparture meeting

A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Overall progress update Itinerary basics outlined Explain revised education outcomes Confirmed field trip outcomes Informed of all accommodation and visa developments

A.6 Actions going forward Pre departure meeting - Mon - Have all docs ready by then (risk, forms, itinerary off james) Book accommodation for first 3 days Modify education program for research whilst in Cambodia PRIORITY: Prepare all documents ready for Cambodia Write report intro and literature review

CP-CBU-125 358

CP-CBU-125 Meeting Minutes - Pre-departure Meeting Date: 03/09/2012 Duration: 1.5 hours A.1 Present All A.2 Regrets

A.3 Follow up from last meeting 14th September - Fly out!!

A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed Insurance accomm cultural and customs brief risk motorbikes no go swap ph numbers and details safety briefing medical briefing travel details and other particulars

A.6 Actions going forward Itinerary off James Book accommodation for first 3 days PRIORITY: Prepare all documents ready for Cambodia Write report intro and literature review CP-CBU-125 359

CP-CBU-125 Write report material that can be completed ahead of time Do smart traveller forms make sheet of contact details and insurance details send insurance and contact deets to terri

CP-CBU-125 360

CP-CBU-125 Meeting Minutes Date: 07/09/2012 Duration: 1 hour A.1 Present All A.2 Regrets

A.3 Follow up from last meeting

A.4 Schedule/Important Upcoming Dates 14th September - Fly out!!

A.5 Tasks Completed google doc of insurance, medicals, contacts, etc Smart traveller - all - done

A.6 Actions going forward fill in details james/ewb/julian/terri on sheet - zac Finalise all documentation to be printed and taken over

CP-CBU-125 361

CP-CBU-125 Meeting Minutes Date: 13/09/2012 Duration: 2 hour A.1 Present All A.2 Regrets

A.3 Follow up from last meeting

A.4 Schedule/Important Upcoming Dates 14th September - Fly out!!

A.5 Tasks Completed Go over all documents ready to take to Cambodia Print all docs Send current progress on final report to Colin Go over final travel stuff before travelling

A.6 Actions going forward

CP-CBU-125 362

CP-CBU-125 Meeting Minutes - Trip to Cambodia Date: 15/09/2012 Duration: 2 weeks A.1 Present All A.2 Regrets A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates A.5 Tasks Completed A.6 Actions going forward

See Diary from the Trip to Cambodia in Appendix N

CP-CBU-125 363

CP-CBU-125 Meeting Minutes Date: 2/10/2012 Duration: 2 hours A.1 Present All A.2 Regrets

A.3 Follow up from last meeting Finalise everything learnt and developed in Cambodia Begin/Complete each section of report

A.4 Schedule/Important Upcoming Dates Fri - combine day! Have all work to 90% by Friday 14th Oct - Poster complete and sent to Endeavour gang 15th Oct - Final report submission

A.5 Tasks Completed Delegation of tasks in next two weeks Settled on standard formats for report Clarified working targets before next tues/Fri

A.6 Actions going forward Complete work to 90% by Friday Big day Friday, be ready

CP-CBU-125 364

CP-CBU-125 Meeting Minutes Date: 5/10/2012 Duration: Zac and Jack 10 hours, Grace and Dave 7 hours A.1 Present All A.2 Regrets A.3 Follow up from last meeting Complete work to 90% by Friday Big day Friday, be ready Finalise everything learnt and developed in Cambodia Begin/Complete each section of report

A.4 Schedule/Important Upcoming Dates Aim for Report to Colin by Tuesday 14th Oct - Poster complete and sent to Endeavour gang 15th Oct - Final report submission

A.5 Tasks Completed Majority of Tank, FF Appendices written and corrected Education body complete and corrected Initial review of entire report and review of intro, executive summary

A.6 Actions going forward Finish All Appendices Write remaining body pieces and correct Once above two points complete, send to Colin (Ideally Tuesday)

CP-CBU-125 365

CP-CBU-125 Meeting Minutes Date: 8/10/2012 Duration: 2 A.1 Present All A.2 Regrets A.3 Follow up from last meeting Finish All Appendices Write remaining body pieces and correct Once above two points complete, send to Colin (Ideally Tuesday)

A.4 Schedule/Important Upcoming Dates Aim for Report to Colin by Tuesday 14th Oct - Poster complete and sent to Endeavour gang 15th Oct - Final report submission

A.5 Tasks Completed Everything mostly complete

A.6 Actions going forward Finish All Appendices Grace to review formatting of some sections Zac to finish his tank parts Dave to do some rewriting of his sections Jack to proof read all report next thurs Once above points complete, send to Colin (Ideally Tuesday) Meeting Minutes CP-CBU-125 366

CP-CBU-125 Date: 14/10/2012 Duration: 3hours A.1 Present All A.2 Regrets

A.3 Follow up from last meeting A.4 Schedule/Important Upcoming Dates 14th Oct - Poster complete and sent to Endeavour gang 15th Oct - Final report submission

A.5 Tasks Completed Everything complete Finish All Appendices Write remaining body pieces and correct Once above two points complete, send to Colin (Ideally Tuesday) Poster Submitted

Final review conducted as a group - all good

A.6 Actions going forward Submit report to Colin and Andrew on Monday via US

CP-CBU-125 367

CP-CBU-125

Appendix H – Timesheet (Project Diary)

Cumulative Hours Worked on Capstone Project 1600

1400

1200

Hours Worked

1000 Jack Grace

800

Dave Zac

600

Total 400

200

0 0

1

2

3

4

5

6

7

8

9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

Week ('Week 1' is the week of the first meeting, starting 7/11/11, and 'Week 0' is all work prior to this)

Figure H.1: Cumulative Hours Worked on Capstone Project CP-CBU-125 368

CP-CBU-125 Table H.1: Project Diary Capstone Timesheet Team Members present Date Jack Grace Dave Zac Area of Work 9/11/11 Yes Yes yes yes Team formation 12/11/11 Yes Yes Yes Yes Meet Colin Meet Colin 15/11/11 Yes Yes yes yes Formally 23/11/11 yes yes yes yes General 4/02/12 yes

yes

yes

5/02/12 yes 26/02/12 yes 28/02/12 yes 2/03/12 6/03/12 6/03/12 6/03/12 6/03/12 7/03/12 7/03/12 7/03/12 8/03/12 8/03/12 8/03/12 9/03/12

yes

yes

yes

yes

yes yes

yes

yes

yes

yes

yes yes yes yes

yes

yes

yes yes yes yes yes

yes

yes yes

yes

yes yes yes yes yes yes

Holiday catchup EWB official documents Meet Julian O'Shea

Outcome and Actions Team formed Met Colin to express interest in Project Met Colin to secure project Project secured, plan for over break, look into research on context Grace to meet James in Cambodia, others to keep her up to date with uni goings on, begin Cambodia research, EWB paperwork

Fill out official forms to receive project, submit to Julian O'Shea Discussion of project, contact details of James Oakley Graces photos and info, set Tues 12 meeting time, begin scope, IA, 1st meeting sem 1 gantt team organising sent emails, called individuals and kept on top of progress gantt chart and scope of project, all to begin FF research and prelim IA research on WASH, forms for ewb/unimelb IA Gantt chart Scope Begun scope submission Research WASH general WASH research Paperwork EWB and Unimelb paperwork finalised Research WASH general WASH research, Cambodian context Research WASH general WASH research Scope Gantt chart Scope Work on scope, discussion of gantt, task break up scope Scope submission ready for draft to Colin, brainstorm session team organising Sent emails, called individuals and kept on top of progress CP-CBU-125

Hours 1 1 0.5 1 1 1 1 1 0.5 3 2 2 3 1 2 2 2 2 3 0.5

369

CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work 12/03/12 yes yes Research WASH 13/03/12 13/03/12 14/03/12 yes 14/03/12 16/03/12 18/03/12 yes 19/03/12 19/03/12 yes

yes

yes

yes yes

yes yes

yes yes yes yes

yes yes yes

20/03/12 yes 20/03/12 Yes 21/03/12 23/03/12

yes

yes

Yes

Yes

yes Meeting Yes FF brainstorm yes Team organising FF research

23/03/12 Yes 25/03/12 25/03/12 26/03/12 Yes

yes

Yes yes

27/03/12 Yes 27/03/12 Yes 29/03/12 Yes 29/03/12 29/03/12

Meeting Team organising WASH research FF research FF research FF research FF research General Research

Planning FF Brainstorm WASH research Research Research

Yes yes yes

Yes

Meeting FF existing write up WASH research FF designs

Outcome and Actions General WASH research Discussion of actions going forward, act on Colin’s comments, once submitted scope, begin research Sent emails, called individuals and kept on top of progress WASH research FF research FF research FF research FF summary doc begin FF, WASH, Cambodian context research, brainstorming Ideas resulting from scribbles and brainstorming, discussion of everyone’s research Initial ideas for first flush system redesign Sent emails, called individuals and kept on top of progress Looking at flow rate controlled Planning specific tasks based on scope document, research into existing systems Considered alternative ways to flush water Researched WASH programmes in developing countries First flush journal research, Found DTU research website Read and saved WHO reports, drinking water guidelines, UNICEF reports, MDG Discussion of progress, Zac to meet with Dreamlarge, FF designs progress Wrote up existing first flush document for pr1 Continued with WASH research Researched existing systems and alternative designs

Hours 2.5 1 0.5 2.5 4 2 3 2 7 1 2 0.5 2 3 3 5.5 8 7 1 4 4 3.5

CP-CBU-125 370

CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work Meet with Dreamlarge Grant 30/03/12 Yes people 30/03/12 yes team organising 30/03/12 Yes FF existing write up 3/04/12 Yes 4/04/12 Yes 4/04/12

Yes

Yes

Yes Meeting Yes Call James yes Team organising

5/04/12 yes

yes

yes

yes

5/04/12 Yes 6/04/12

yes

6/04/12 Yes 7/04/12

Yes

11/04/12 Yes 11/04/12 12/04/12 Yes 13/04/12 13/04/12

yes

16/04/12

Yes

Yes Yes

Poster presentation RWC background research RWC background yes research Brainstorming Yes session FF designs Began PR2 documentation yes Team organising Started endnote library for Capstone Risk Assessment Yes Dream large Grant

Outcome and Actions Discussed the grant and got recommendations on what to include in the application Sent emails, called individuals and kept on top of progress Finished FF initial document and sent to James and Colin Confusion over James’ comments - contact him regarding scope, ff research largely complete Tried calling James but no response Sent emails, called individuals and kept on top of progress Discussion of poster presentation for EWB Humanitarian Research Conference Prepare docs on summary of RWC's background

Hours

1.5 0.5 2 1 0.5 0.5

2

Summary of RWC's background Brainstorming session to come up with new FF ideas, very productive, 2 new concept designs Further developed new 'waterwheel' concept, inc. sketches

1.5

Wrote intro, copied ff review, made James and Colin's changes Sent emails, called individuals and kept on top of progress

4 0.5

Added all research entries, sparked additional research Reviewed objectives for risk assessment and prepared rough draft Researched and discussed the various grants Met with Frank for assistance with writing the risk assessment

Risk Assessment Meeting

3 3

6 3 1

1.5 CP-CBU-125 371

CP-CBU-125

Hours

Team Members Present Jack Grace Dave Zac Area of Work

17/04/12 Yes 18/04/12 18/04/12 18/04/12 21/04/12

Yes

Yes Meeting Endeavour Risk Assessment Meeting Meeting - James Oakley over Yes skype/phone Risk Assessment Yes Extra Meeting Yes Dreamlarge Grant

Yes Yes

24/04/12

yes

26/04/12 Yes 25/04/12 27/04/12 28/04/12 28/04/12 yes 29/04/12

Yes Meeting Yes Dream large Grant Risk Assessment yes Team organising Risk Assessment

Yes

24/04/12 Yes 24/04/12 Yes

24/04/12 Yes 24/04/12 25/04/12 Yes 25/04/12

Yes

yes Yes

Yes

Yes

Yes

Outcome and Actions First meet back after mid semester break, progress on hold until hear back from James Started the skeleton of the application Began write up of Risk Assessment for Dreamlarge Grant Sent emails, called individuals and kept on top of progress Finished off formatting of risk assessment No further progress, trying to contact James, made time to call him over skype, prepared list of agenda items Put together a summary for the Endeavour Description

Scope document Yes Dream large Grant Risk Assessment yes Team organising Scope FF designs

30/04/12

Yes

FF designs

1/05/12

Yes

FF write up

Second meeting with Frank to revise risk assessment draft skype useless, ended up using phone. Outcome of meeting, project scope has changed entirely. Need to sit down with entire team and discuss Completed Risk Assessment for Dreamlarge Grant Discussion over meeting with James, new scope of project Finished intro Prepared new scope document based on James comments and group discussion Worked on the first review of the budget for the Dreamlarge Grant Worked on the risk assessment Sent emails, called individuals and kept on top of progress Prepared a breakdown of new tasks to add to scope for group approval Commenced formal evaluation of existing and new designs Continued evaluation, pros/cons of each design Write up explaining all existing and new designs

Hours 1 4 3.5 0.5 1.5 1 0.5 1.5

1 1 3 4 3 2 2.5 0.5 1 1.5 4 4

CP-CBU-125 372

CP-CBU-125

Hours

Team Members Present Jack Grace Dave Zac Area of Work

1/05/12 Yes 1/05/12 Yes

Yes

3/05/12 Yes 4/05/12 5/05/12 5/05/12 Yes 6/05/12 7/05/12 Yes 7/05/12 Yes

Yes Meeting New documents

yes

New documents FF designs Reviewed new docs

Yes

Yes Yes yes yes

Poster presentation Poster presentation Tank research Tank research

Yes Yes Yes

EWB conference Yes EWB conference EWB conference Yes EWB conference

Yes

Yes EWB conference Poster presentation Yes EWB conference

Yes

Yes

8/05/12 8/05/12 Yes 9/05/12 Yes 10/05/12 Yes

Yes Yes Yes

11/05/12 Yes 11/05/12 Yes 12/05/12 Yes

Yes Yes Yes

14/05/12 Yes

New reading

15/05/12 Yes

Research

Outcome and Actions Discussion of new scope, went through scope document and made additions, James has added comments to existing system doc Read all James documentation he sent us through dropbox Read all James documentation he sent us through dropbox, sent James document to confirm we are all on the same page Drew up FF designs Reviewed sizing spreadsheet, existing tanks doc Discussion of poster presentation for EWB Humanitarian Research Conference Started tanks section Initial research into tank and gutter systems Looking further into tanks, leaf filters, sizing Created slideshow presentation for, wrote, and rehearsed FF section of presentation Put together a presentation for the EWB Research conference Created a slideshow to present at the conference Rehearsed presentation Networked with students and professionals at the Research conference dinner Made presentation at last minute, Julian forgot to tell us Presented at the 2012 EWB Humanitarian Research Conference Read Jane and Klyti's material on RWH and Cambodia (RWC specifically) Initial research into system sizing based on Janes work and also other members at forum

Hours 1 6 15 3 5 2 2 4 4 4 4 2 2 4 4 9 6

3 Reviewed what was required from team members for grant application

15/05/12 Yes

Yes

Yes

Yes Dream large Grant

1 CP-CBU-125 373

CP-CBU-125

Hours

Team Members Present Jack Grace Dave Zac Area of Work

15/05/12 Yes 15/05/12 16/05/12 17/05/12

Yes

Yes

Yes Yes Yes Yes

17/05/12 yes

yes

yes

yes

18/05/12 18/05/12 18/05/12

22/05/12 Yes 22/05/12 yes 23/05/12 23/05/12

Yes Dreamlarge Grant yes team organising Progress Report 1

yes

Yes

Yes

Yes Yes Yes Yes

23/05/12 27/05/12 yes 28/5/12 End Semester 1 11/06/12 Yes 11/06/12

Meeting Dreamlarge Grant Dreamlarge Grant Dreamlarge Grant Endeavour photoshoot

yes

Meeting Dreamlarge Grant Dreamlarge Grant Dreamlarge Grant Discussion with Niruma Akhter, ARUP (Tech mentor) EWB Risk Assessment

Team organising

Outcome and Actions Follow up on research forum, collaboration of ideas coming from event, now to focus on PR1 and existing systems/research continues Finalised first draft of the budget and sent to James Oakliegh Reviewed James comments on budget and made relevant changes Finished first draft of dreamlarge grant Attended the Endeavour Photoshoot Wrote an example of what was required for a recommendation from EWB and sent to Julian Sent emails, called individuals and kept on top of progress Edited and reformatted Progress Report one Discussion of exams - no work capstone work until afterwards, PR1 submitted, colin giving feedback today on Dreamlarge submission, aim to continue some research over holidays but many people overseas - tricky Reviewed Colin's suggestions and made ralevant changes Got relevant signatures and printed dreamlarge application Submitted the application

Hours 1 2 1.5 4 0.5 1 0.5 5.5

1 2 1 1

Discussion with Niruma about leak and tank issues

1

Reviewed and updated current Risk Assessment

1

Discussion with James over email of developments, emailed to whole group Sent emails, called individuals and kept on top of progress

0.5 0.5

CP-CBU-125 374

CP-CBU-125

Hours 23/7/12

Team Members Present Jack Grace Dave Zac Area of Work Start Semester 2

24/07/12 Yes 24/07/12 Yes 27/07/12 Yes 27/07/12 29/07/12

Yes

31/07/12 yes 31/07/12 Yes 31/07/12 31/07/12 2/08/12 3/08/12 3/08/12 Yes 3/08/12

yes

yes yes yes Yes

yes

yes Yes Yes Yes

yes

7/08/12

8/08/12

yes

yes yes

4/08/12 4/08/12 Yes

7/08/12 yes

Yes

Yes

yes

Outcome and Actions

Meeting Tank research Research Education Research Education Research

Meeting PR2 writeup PR 2 Education Research Progress report 2 Education Research Write up PR2 Education Research Education Research Built test rig

yes

Progress report 2

Yes

FF test planning

yes

Meeting with Nossal Institute

Discussion of project direction and holiday developments, decision to split up tasks to accomplish more now research background is solid DTU website and Mart thesis, alt tank research Tank, sizing, gutter research, overflows, all in endnote Began to research literature review for education Continued to research literature review for education Dreamlarge success!, update and review of team members work, split up tasks; Grace - education, Jack and Zac - Tanks and reports, Dave FF, discussion of ideas going forward, keep same meet time Began write up to see where gaps in information were Education write up for PR 2 Researched and obtained relevant journals for David to read Individual work towards PR2 Continued to research literature review for education Existing systems alternatives write-up Commenced reading and summarising allocated papers Finished reading and summarising allocated papers, sent to Grace to incorporate into Education section Built test rig on rural property in Victoria Reviewed current work by individuals for progress report 2, all to read summary thesis by dbm, look into flights, itinerary, start writing everything new up for PR2 Researched relevant rainfall intensity data, used in conjunction with system information to estimate operational flow rates Discussed project, ideas, concerns. Feedback. Set 2nd meeting

Hours

2 5 4 4.5 6

2 4 3.5 1.5 3 4 5 1.5 5 8

1 5

1.5 CP-CBU-125 375

CP-CBU-125

Hours

Team Members Present Jack Grace Dave Zac Area of Work

9/08/12 9/08/12

Yes

FF Prototyping Education research in Cambodia

yes

9/08/12 Yes

10/08/12 Yes

Yes

MGMT tasks Extra meeting to prepare slides for Yes PR2 presentation

10/08/12

Yes

2nd Meeting with Yes Nossal Institute

10/08/12 10/08/12 Yes 11/08/12

Yes yes Yes

11/08/12 11/08/12 12/08/12 13/08/12

Yes

14/08/12 Yes

Yes

14/08/12 Yes

Yes

Slides combined and many removed due to time constraints, more coverage needed in FF and tanks Consultation with Associate Professor Jim Black and Naomi Francis, on the education aspect of the project. Received valuable feedback and ideas Sourced and purchased parts for first ff valve prototype, conducted 'test 1' to establish required ball height, continued canvas waterbag material porosity testing Write up of tanks complete Constructed first FF valve prototype Review and summarised education section up-to-date for progress report 2 Canvas waterbag material testing Constructed 'mock gutter' and set up test rig for FF testing FF valve prototype modification Presentation rehearsals, cut out a few more slides, got timings correct, feedback on each others presentation skills, confirmed room booking for presentation Excellent presentation, well received, Colin gave valuable feedback see minutes

FF Prototyping Tanks FF Prototyping

Yes

Education review FF Prototyping FF Prototyping FF Prototyping Extra meeting for PR2 presentation Yes rehearsal

Yes

PR2 Presentation Yes Colin

Yes Yes Yes

Outcome and Actions Sourced and purchased canvas waterbag, commenced material porosity test Using the feedback from Nossal began creating objectives of research in Cambodia Review and update of all gantt charts, meeting minutes and timesheets for PR2

Hours 2 3 2

2.5

1.5

4 3 4 2.5 0.25 3 3

2

1

CP-CBU-125 376

CP-CBU-125

Hours

Team Members Present Jack Grace Dave Zac Area of Work

14/08/12 Yes 16/08/12 Yes 16/08/12 Yes 16/08/12

Yes Yes

Yes

Yes

18/08/12 Yes

PR2 Presentation Yes Andrew Wirth Yes Extra meeting PR2 FF Prototyping Yes Build session

18/08/12

Yes

FF Prototyping Human Ethics Approval

19/08/12

yes

21/08/12 Yes

Yes

21/08/12

yes

Yes Meeting Education: 2008 RWC's report

22/08/12

yes

yes

22/08/12 23/08/12 Yes

yes

23/08/12 23/08/12 Yes 24/08/12 Yes 24/08/12

Yes

25/08/12

Yes

Yes

yes

yes Yes

Nossal Meeting Education: 2008 RWC's report Meet Colin Education Questionnaire James Book flights Endeavour Forms Education Questionnaire

Outcome and Actions Good presentation, extra info presented for Andrew at the end, lots of questions, seemed pleased, make sure to send him through copies of our pres and reports Need to resubmit PR2, not punchy enough redo some parts of PR2 Conducted bulk of flow rate testing on first FF valve prototype Built education model, purchased tarp tank components, prepared concept ideas for FF construction First FF valve prototype write up, including recommendations for second prototype

Hours

1 2 3 5 7 4

Looked into the Human Ethics Approval PR2 complete, begin write up, jack to sort out forms and travel insurance and flights, rest to begin writing up findings

0.5

Read and summarised 2 reports provided by RWC Met with Associate Professor Jim Black and PhD student Naomi Francis to discuss the education section for the project

6.5

Completed reading reports and summarising Got extension approval until 15th Began to prepare a questionnaire for recipients and non-recipients of RWH Discuss itinerary with James and other EWB document agenda Book flights - give flight numbers to group Completed the required Endeavour Forms for the exhibition day Completed the questionnaire for research in Cambodia and emailed it to Professor Jim Black and Naomi

2.5 0.5

1

1.5

3 1 1 0.5 3.5

CP-CBU-125 377

CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work 25/08/12 Yes Final Report 27/08/12 Yes Final Report 27/08/12 27/08/12 Yes 27/08/12

yes

28/08/12 Yes 28/08/12 Yes 28/08/12 Yes

Yes yes

28/08/12

Yes

28/08/12 Yes

yes

yes Yes Yes

Yes

28/08/12 Yes

29/08/12 Yes

29/08/12

30/08/12

Outcome and Actions Commenced work on FF appendices Further work on FF appendices Organised and began preparations for the research to be conducted in Education Research Cambodia. Emailed James about the proposal Final report skeleton Wrote final report skeleton and executive summary draft Final report proof Read report plan Write up progress discussion, general team discussions, insurance and Yes Meeting travel stuff discussed, final report structure discussed yes Extra meeting Paperwork for UoM, EWB, insurance forms etc. Insurance Sort out insurance with Jan at MSE Grace discussion of education with Julian O'Shea Covered the proposed education scope, received feedback Meeting via phone with Terri Maher, EWB field placement officer in Initial contact, set briefing date for 2pm Monday, list of things to Yes Cambodia prepare before then - see minutes Meeting with James Update on project, itinerary discussion, James movements while we Yes Oakley via skype are in Cambodia, dates times, Draft of intro and executive summary, and structure of report started Final report writing Education questionnaire for Cambodia

yes

Yes

Hours 3 3 2.5 7 0.5 1 2 0.5

0.5

1 1

6 Revised initial questionnaire and began writing up revised questionnaire for Cambodia Constructed 'canvas bag' test prototype, tested denim, artists' canvas, and waterbag canvas for porosity and with fastening mechanism

FF Prototyping

5.5

4.5 CP-CBU-125 378

CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work Education questionnaire for 30/08/12 yes Cambodia 31/08/12 31/08/12 Yes

yes

1/09/12 1/09/12 Yes 1/09/12

Education Booklet Final report Yes

yes

2/09/12 2/09/12 Yes

Yes

2/09/12

yes

2/09/12

Yes

2/09/12 3/09/12 3/09/12 Yes

Yes

3/09/12 Yes

Yes

3/09/12 4/09/12

yes

Yes

Yes

Yes

FF Prototyping Build Tarp tank Education questionnaire

FF Prototyping Build Tarp tank Final Report Education Education Lit review Risk Assessment for EWB FF Prototyping RFinal Report

Outcome and Actions

Hours

Completed revised questionnaire for Cambodia Researched the different learning and teaching styles for the booklet that is to be given to RWC Finished intro and lit review drafts in skeleton Sewed fitted canvas bag, made detailed plans for second FF valve prototype Construction of low cost tarp tank

3.5

Read the feedback from Nossal and edited questionnaire Purchased parts for and constructed majority of second FF valve prototype. Conducted flow rate and drainage testing on canvas bag prototype. Construction of low cost tarp tank

2.5

Drafted layout and structure for the education section of the report Added to the literature review table and edited current education literature review Updated risk assessment, add additional information and format

3

Continued flow rate testing of first prototype Began tank section of final report in skeleton EWB Pre-departure brief including risk analysis, country stuff, etc Yes Pre-Departure brief see minutes Continued to research the different learning and teaching styles for the Education Booklet booklet FF analysis Analysed test results, tabulated results on computer CP-CBU-125

4.5 8 4 5

8 4

4

4.5 3 4 1.5 3 4

379

CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work 4/9/12 Yes Tarp tank manual Risk Assessment for 4/09/12 yes EWB 4/09/12 Yes FF Prototyping Literature review 4/09/12 Yes write up Education review 5/09/12 yes write up 5/09/12 Yes FF analysis Gathered construction manuals for 5/09/12 yes alternative tank 5/09/12 Yes Education Pamphlet Education review 5/09/12 yes write up

5/09/12 Yes 6/09/12

yes

6/09/12 Yes 6/09/12

6/06/12

yes

yes

MGMT tasks Final report education template Management task cataloguing for final report Literature review write up

Outcome and Actions Wrote up tarp tank construction manual, printed ready to give to RWC Edited risk assessment after receiving feedback from EWB Completed construction of second FF valve prototype Began write up of lit review version 2

Hours 6 1.5 6 5

Write up of education review summary and tables of summary Created charts from test results, write up of results and procedures etc.

4.5 5

Found construction manuals for alternative tanks Researched information to be placed in pamphlet

6 3.5

Continued to write up education review Finalised all MGMT tasks, minutes, timesheets, EWB and unimelb documents, insurance details, stuff with MSE, blogs and photos for MSE, spoke to Colin about trip Finished off education template for final report Getting together and inserting gantt charts, appendices, minutes, timesheets, design diaries Continued lit review for tanks Research on different pamphlet format and templates. appropriate font etc.

Education Pamphlet

2

3 3.5

2 5

4.5

CP-CBU-125 380

CP-CBU-125

Hours 7/09/12 7/09/12 8/09/12 8/09/12

Team Members Present Jack Grace Dave Zac Yes Yes Yes Yes Yes Yes yes

9/09/12

Yes

9/09/12

yes

9/09/12

Yes

9/09/12 9/09/12 9/09/12 10/09/12

yes yes

10/09/12 Yes 11/09/12

yes

11/09/12

yes

12/09/12 Yes 12/09/12

yes

12/09/12 12/09/12 13/09/12 Yes

FF appendices Final Report Education

yes

Yes

yes Yes

Area of Work FF appendices Meeting FF appendices Cost analysis

Education Booklet Book accommodation Education Pamphlet Cost analysis FF appendices Writing up Appendices Education Booklet Education preparation for trip First draft at final report Education Pamphlet Education preparation for trip FF Prototyping

Yes Tanks

Outcome and Actions Photographed and documented progres, work on FF appendices Travel bits and pieces, accom, contact sheet, get stuff for Cambodia Commenced consolidated previous written work into appendices Worked on cost analysis spreadsheet Continued consolidation of previous written work into appendices, sourced and referenced figures, made layout decisions for appendices Continued to work on structure and content for education report, and began writing research process Write up the findings and research in a suitable format/booklet which is to be handed to RWC during the team's visit

Hours 4 1 5 8 6 3.5 4

Researched appropriate accommodation for team and booked Designed and drafted education pamphlet Worked on cost analysis spreadsheet Further work on FF appendices

2 3.5 8 5

Writing up Appendices and Literature review (Tanks) Finished off education booklet for RWC Write up of finalised questionnaire and objectives for research in Cambodia Writing up Appendices and Literature review, included all appendices, majority of tank appendix is done Continued to design education pamphlet Edited and reviewed objectives for research in Cambodia. Edited final questionnaire Flow rate testing on second FF valve prototype Writing up to final report standard much of the tank info, documents for Cambodia

8.5 3.5 2.5 6 2.5 3.5 5 3

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CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work 13/09/12 yes Education Pamphlet First draft at final 14/09/12 Yes report 12/09/12 yes Education Booklet 14/09/12 Yes Travel documents 17/09/12 18/09/12 19/09/12 20/09/12 21/09/12

yes yes yes yes yes

yes yes yes yes yes

23/09/12

yes

23/09/12 23/09/12 24/09/12

yes

24/09/12 25/09/12 Yes

Yes

yes yes yes yes yes

Yes Yes

25/09/12

Yes

25/09/12 26/09/12 Yes

yes

27/09/12

Yes

yes yes yes yes yes

Field work Field work Field work Field work Field work Final report education Final report education FF theory Yes FF referencing Final report education Tanks Yes FF theory Final report education Scoping section Final report education

Outcome and Actions Completed education pamphlet

Hours 1.5

Worked on tank section and intro Finished off booklet for RWC Preparing and printing all documentation for RWC

4

Work at RWC (refer to diaries) Work at RWC (refer to diaries) Work at RWC (refer to diaries) Work at RWC (refer to diaries) Work at RWC (refer to diaries)

9 9 9 9 9

Collated all 4 diary entries for quotes and research notes Finished off write-up for education scope development and research community engagement Started theoretical flow rate calculations for various designs Formalised referencing for appendices Summarised and started writing the summary of findings, began writing the education background Write-up of tanks developments Theoretical calculations of FF flow rate for various designs, compared to results Finished off summary of findings, worked on research process write up Final report scoping section, tank appendices, calcs for FF sizing Continued to work on education section, appendices and semiformatting

2

1.5 6 2 4 9 7 5 7.5 8

8 CP-CBU-125 382

CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work Tank appendices, 27/09/12 Yes photos in report Vice-Chancellors Engagement Award 28/09/12 yes Ceremony 30/09/12

Yes

30/09/12 Yes 1/10/12 1/10/12 2/10/12 Yes 1/10/12 3/10/12

Yes

Yes

Yes

Yes

3/10/12 3/10/12 Yes 4/10/12 4/10/12 4/10/12 5/10/12 5/10/12 Yes 5/10/12

Yes

Yes

Yes Flow Rate theory Working from KL airport! FF charts Sustainability Yes Application Yes Meeting yes Cost analysis FF Body Sustainability Yes Application Final Report Tanks FF Body Sustainability Yes Application Yes Tank appendices FF Body Final report editing Sustainability Yes Application

Outcome and Actions Final report work, photos, materials, costs, finished existing systems doc

Hours

Attended the Vice-Chancellors award ceremony Work on MATLAB programs to create charts for sizing of first flush in terms of hole-size, diameter, flow rate etc. for design purposes

3.5

7

6

More work on tank appendices, MGMT tasks, structure of report Continued work on MATLAB script for FF design charts

4 5

Frame work of application and CAPEX started See Minutes Worked on cost analysis spreadsheet Planned what to be included in body of report. Set out structure

8 2 8 5

Finished Capex, Finished first daft of discussion Finish individual section for tank report Moved necessary sections from appendices to body. Formalised evaluation tables etc.

4 6

Finished Appendix of Tables and Figures Worked on appendix for tank section Worked on body of FF section Final report editing

4 4 5 3

Made appropriate changes to report and submitted

4

6

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CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work 5/10/12 yes Education lit review 5/10/12 Yes Yes Yes Yes Combine Day Further Combine 5/10/12 Yes Yes Day 6/10/12 6/10/12 8/10/12 8/10/12 yes 8/10/12 Yes

Yes yes yes

Yes yes

yes

FF cost body lit review write up FF Body Meeting Endeavour Poster

8/10/12 8/10/12 Yes

Yes

FF appendices Final Report Edit

9/10/12

Yes

FF analysis

9/10/12 10/10/12 10/10/12

yes

10/10/12

yes

10/10/12 11/10/12 Yes 11/10/12 11/10/12 Yes 12/10/12 12/10/12 Yes

yes Yes Yes

Final Report Edit FF Body FF referencing Final Report Edit

yes Yes Yes yes

Final Report Edit MGMT tasks Final Report Edit Proof Final Report Design Diary Proof Final Report

Outcome and Actions Edited and partially re-wrote the literature review for education See minutes See minutes Read Zac's cost analysis of FF. Summarised and tabulated relevant data for report. Completed tanks lit review Finished first draft of FF body Made poster for endeavour and split up tasks for endeavour expo Re-calculated estimated flow rates with known system dimensions for appendices, researched and wrote up reset-time calcs Writing and rewriting report edits Noticed unexpected result, investigated and postulated theory

Hours 2 7 3 4 8 6 2 6 5 1 4

Continued to edit sections of the final report, focusing on the project scope development Condensed prose and formatted pictures to get page count down. Formalised referencing for body Finished editing and formatting Education & Appendix. Revised education pamphlet Nearly finished tank appendix. Edited scoping section. Reviewed ff section Finalise MGMT tasks Proof read and edited body of report Proof read final report for errors Compiled sketches & ideas from various notebooks into design diary Proof read final report for errors

4 5 2 7 5 2 4 7.5 3 6

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CP-CBU-125 Team Members Present Hours Jack Grace Dave Zac Area of Work 13/10/12 Yes Finalising FF report 13/10/12 Yes Timesheet Final re-read and 14/10/12 Yes changes 14/10/12 Yes Yes Yes Final read

Outcome and Actions Finishing touches, formatting, minor changes to FF sections Formatted timesheet in excel, created totals, weekly totals, charts etc. Finalised document Final read through before submit

Hours 4 6 10 3

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Appendix I - Design Diary See paper submission for design diary appendices

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Appendix J - Field Work in Cambodia J1 – Day 1 Date: 17/09/2012 People: James, Kia, Zac, Jack, David, Grace and 3 RWC employees Activities:  visited RWC  presented presentation and current progress and findings  Had the opportunity to learn about education and key points that target the education objectives  Discussed FF system with RWC  Went to market to price materials, purchased ½ metre of 2 chain sizes, still have to look for suitable materials for canvas bag idea  Decided on what we are going to prototype: o Semi-underground tarpaulin tank o Canvas-bag (test with various materials and angles, measuring flow rate & 90% reset time o Baseline testing on current system (flow rate, 90% reset time, including varying angles & hole size) o Chain downpipe  Completed questionnaire Quotes:  “We put in first flush into a villiage, 30 or 40, and two years later they were all gone. We don’t know why. We don’t know if it is because the first flush didn’t work or if there were other reasons. This is why we need to constantly review what we do but we do not have the money for it. A research group that focused on the technical and the social would be wanted” Further Notes: Grace was able to learn a lot about RWC’s education programs and some of the issues and work that RWC would like future groups to work on. Below is a list of the main and interesting points:  RWC has 8 employees and 5 contractors  Three main technical issues RWC encounters: 1) leakages 2) lack of maintenance 3) costs  RWC has a water hygiene and sanitation program that they have/are implementing. These programs cover two districts. The process is outlined as follows: o RWC team members (program officer) received training from the Ministry of Rural Development regarding water, sanitation and hygiene practices o RWC trained members train key promoter and PDRD o Key promoter and PDRD then train the village locals. CP-CBU-125 387

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  







 

 

 

o 5 locals from each village are trained o There locals then implement the 7 step guide/process (outlined by CLTR) o This program is aimed for schools and communities, to date the community program has been implemented, the school program is to be implemented soon FF systems were installed in one particular village but were found to have been removed 12 months. The reason for this was unknown due to lack of follow up Reset time has not been measured for current system, but probably around 2mins Rainfall is generally heavy for half a day then stops. Not generally on again off again every few minutes, meaning fast reset time is not a big issue. This makes the waterwheel design more promising as a very fast reset time is difficult to avoid. All partners agreed the following developments were promising: o Chain idea o Tilting the first flush o Heshen sack o Overflow from the bottom of the tank o Use of floating hose o Funnel pipe to fix the leaking problem It was agreed that the following prototypes need further development: o Water wheel o Both ping pong ball first flush prototypes Every month RWC meets with other local NGOs (about 20 or so) who work with water, hygiene and sanitation. They discuss their findings and what they are doing. This ensures that even though they may teach/implement different programs, the context is very similar RWC has designed many posters that promote good practice hygiene and sanitation. These posters are presented during the meetings to visually show good practices Apart from continuing to work on our team’s current work, one other area that RWC would like to see future groups work on would be research. Due to cost restrictions, RWC does not have the funding for evaluation research, as such they would like to see a future group help them to identify the impacts, success and benefits of the rainwater harvesting tanks. Unfortunately after installation, they can not monitor their work RWC has a field officer who is responsible for overseeing the construction process RWC has an evaluation team who is responsible for “validating” and evaluating the system once construction is completed. They have two evaluations; at the first evaluation they pay the contractors 90% of the payment, after the second evaluation (about one month or so) they pay the remaining 10%. This is done to ensure that the tanks that have been built, have been built well/ serve their purpose at least after a month About 80-90% of Cambodians prefer rainwater to drink and understand the importance of why it Is good for them Reasons as to why some people may not be able to purchase even the subsidised and affordable tanks are: 1) saving for other things 2) payment of the tanks/project CP-CBU-125 388

CP-CBU-125 duration is within a certain time period, consequently there is enough time to save the money

J2 – Day 2 Date: 18/09/2012 People: James, RWC translator, RWB technician, health centre manager and workers, four household owners Krainserey, kirivong commune, phnom srouch district Activities: Visited health centre and four village households, asked questions about RWH systems, in particular FF use. Quotes: Households  “ rainwater tastier”  “people boil water because NGO educate community”  “when get water from mountain more diarrhoea”  “many NGO come to teach about sanitation and hygiene”  “learn to boil water from NGO”  “When I receive a tank I very happy because I get less sick and I know more about sanitation”  Eight people in my household  “NGO organise training”  “Go to pond to wash. It is 5m away”  “With the spare time I do more agriculture and look after the kids more”  “Since tank kids get no diarrhoea”  “I have clean water but this does not fix my income problem. I am still very poor”  “I decided to get the tank myself”  “All members of the family maintain the tank”  “All members of the family go to learn sanitation. We take in turns to go”  “12 people in committee to maintain tanks”  “I block the hole in the [in the first flush] because it wastes too much water”  “I never take the stick out” Local businessman:  

When a village gets tank in their house it is easy because they normally walk to carry water for three kilometres to fill 200 litres on a cart every day” “Tank water taste better” CP-CBU-125 389

CP-CBU-125      

“When i have tank my health and family improve” “I use the spare time to work and study at health centre” “UNDP built pond and pipe water system to supply village. We boil or filter rainwater before drinking” The pond supply 61 people in rainy season. It runs dry in the dry season” “25 families in the village have four tanks each” “Family with no tank collect pond water in their village”

Community health centre chief: 

“After Rainwater Cambodia come her more community have more understanding about drinking water and hygiene”

James:  “fundamental cause of illness if lack of education”  “When we apply for funding we detail our project and if it fits in the scope of an organisation like aus aid we get the funding. There is more of a push for follow up so it is an option to do less tanks and follow up more”

Further Notes: Answers to Grace’s questions from last household’s female owner: 

      

Two small jumbo jars are catching water off thatch roof. The smaller is covered, the medium one not. She said this is to keep the leaves out, but that the medium one cannot be covered, as it needs to catch the water falling from the gutter. She always boils her (drinking?) water, she learnt to boil it from an NGO. Used to get water from the mountains, and got diarrhoea, even though she boiled it. She finds it much easier not having to go back and forth for water, she uses the extra time for gardening. She used to get diarrhoea, but not anymore. She has much better health and her husband doesn’t need to go to the health centre all the time like he used to. She is still poor There are meetings and education all the time, at the commune hall, once a month sometimes four times a month, on health and sanitation etc. Households with no tanks use ceramic filters or boil the water.

Education and Current Circumstantial Notes: Once again an excellent day where we visited a health centre and village, and had the opportunity to talk to the families about their tanks, and any other questions we were CP-CBU-125 390

CP-CBU-125 interested in finding answers to. Below is a quick summary of a few points. First stop of the day was to the health centre        

Issue: water coming out from the airvent in the pipe, realised that this was due to the first flush system being blocked. Seems that it is not due to lack of maintanence but the design, that is the pipes were too small Health chief was responsible for maintaining the system and keeping animals and children away from the tanks. The health centre have a committee of 9 people who teach patients about hygiene and sanitation Most of the teaching is done verbally to the patients 300-400 patients per month The health centre tank was installed in 2010 The water is used for washing patients and drinking

After the health centres we visited the village and numerous households                     

61 families, 25 households with tanks UNDP created a very large pond that collects and stores rainwater during the wet season. Locals are able to access the rainwater collected, the water is channelled through pipes to their house 1st household had 4 concrete ring tanks that were installed in 2005 & 2006 RWC trained and taught 3 people in the village about the system, these three people are now the village technicians. Village has a committee of 5 people who maintain 5 households with tanks 1st household always boiled water before drinking Before tanks were installed, 1 st household would travel 3hrs to obtain water. 200L were collected on each visit, and lasted only 1 day With the system being installed, the family now uses the time for work Issue: seal became brittle and the ball broke (shrinkage) 1st household had 7 people 2nd household 9 people Used jumbo jar tanks Issue: nothing technically wrong with the system but the hole was blocked by a twig The twig is never removed, and was placed there as a means to conserve water Water in the jar lasts all year for cooking and drinking 3rd household had 8 people Water was used only for drinking or cooking There was a pond 10m behind the house for washing Issues: broken first flush system, broke from the wind, not enough money to replace CP-CBU-125 391

CP-CBU-125 Recommendation: 

We advise the use of global health researchers, either from a university or professionals, to do an in depth research into what is and what is not working with the systems

First Flush Notes: 1. First Household  FF still in place  Stick was jammed in drainage hole. Owner said this was to keep the water flowing into the tank, as the ball was broken and replacement balls are not available at the local market. As far as I can tell the ball should have nothing to do with keeping the water flowing into the tank. We think he removes the stick from time to time to empty the chamber.  When the stick was removed, water ran out much faster than I had expected. We hope to measure flow rates tomorrow.  The owner had installed a piece of half pipe over the hole so that the flushed water flowed into a small jumbo jar and was not wasted. This bucket was full, suggesting the FF may be used at least some of the time. 2. Second Household  Stick was jammed into the drainage hole and never removed. Again, when removed the flow rate was very high. 3. Third Household  FF had a water bottle with the side cut out over the drainage hole, directing water into a small jumbo jar, which was full. The system appeared to be working correctly, and he said he had recently cleaned it. 4. Fourth Household  FF was not there. A plastic bag was tied around the T-junction to which the FF was originally connected to seal it. The owner said it had blown off in the wind, and was too expensive to replace. Generally: 



The first flush is not being used correctly in most households we visited. Commonly a stick is stuck in the hole. If we can make it seem like not so much water is being “wasted” and can suggest the use of a jumbo jar to catch the first flush water for washing, it is possible they will be more inclined to use the first flush properly. We will look at changing the first flush and adding a chain tomorrow and advise RWC to the need a further project required for first flush at the end of the week.

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Tank Notes: 



  

The bean jars are so cheap, at $7.50, this is suitable for use as a smaller storage for second class water. There is no real need to build wooden tank as wood is so expensive The larger ring tanks do not need replacing, however different large tanks can be developed, like the semi-submerged dome tank, and put on the market as an alternative choice. As these are developed they may become well built and cheap There is possibly a project for next year to look at computer modelling to make the tanks as cheap as possible We suggest that the overflow of the tank comes from the bottom to de-sludge and save cleanest water. This will also help solve the leaking issue We suggest a floating hose pipe for extraction

J3 – Day 3 There are two separate entries for day 3 as Grace split from the main group to visit a school while the remaining members ran tests on the existing system and innovations. Main Group: Date: 19/09/2012 People: Zac, Jack, James, Van, Activities: Tested existing system (flow rate and reset time), tested chain, implemented canvas bag on existing system. Quotes: Further Notes: Flow rate was much higher than expected, due to the larger than anticipated hole, at close to 1.5L/min when the system is full (i.e. when it is raining).

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Grace: Date: 19/09/2012 People: Grace and Sokhol

Activities: visited a school in Phnom Penh and talked with the principal Quotes: -

“before tank installed, had to pay for water, very expensive” When talking to Sokhol, and asked whether or not Cambodia has improved in the last 10 years, he replied “yes improve but little in hygiene” when asked why, “people don’t want to listen to NGO or TV as like to watch movie and no money to build latrines”

Further Notes:  Spoke to the principal of the school  Tank was installed in 2011  The tank holds 330000L  NGO CSCS came to the school 3 years ago and taught the teachers and students about hygiene and sanitation.  The school teaches hygiene and sanitation every Thursday for 2 hours  The learn by practical action of washing hands, writing, painting or verbal  The children practice washing their hands everyday in the classroom  Rainwater from the tank is directed to 2 drinking stations and 2 hand washing stations  Water is collected in a bucket and placed through a water filter , located in the classroom  Before the tank was installed, water was obtained from the wells on the school property, however quality of the water wasn’t very good, so they had to buy water from private company/person who sells bottle water.  The tanks supplies water for 6 months of the year, the school purchases water for the remainder of the month  The children do not have to pay to attend school  300 students ranging from age 5 to 16 years old  The school teaches Year 1 to year 9  As the students were on vacation the school was quite empty and bare, nonetheless principal said that when school returns, posters of hygiene and sanitation are placed all around the school  Phnom Penh parents teach their children to wash their hands as most have some level of education.  The schools teaches the 6 step process for washing hands CP-CBU-125 394

CP-CBU-125 J4 – Day 4 Date: 20/09/2012 People: Zac, David, Jack Activities:     

Checked progress of the bag after heavy rain the previous night. The bag worked Put dirt in the bag and timed how long it took to drain the first flush. This took 8 hours Tested existing system flow rate at angles from 0 degrees to 75 degrees Built test rig comprising of a clear system and a full first flush system with interchangeable ends which could rotate to angle the system Built and tested new prototype “Chlorine type filter end cap”. This worked better than the current system, however was only glued and did not last long

Quotes: James Oakley: 

“The chlorine cap seems to be very promising”

Further Notes:  

Tank overflow needs to be tested tomorrow Chlorine cap needs to be fixed

J5 – Day 5 Date: 21/09/2012 People: Zac, Jack Activities:  Tested alternative overflow design for tanks. We used berries at the bottom of the tank with clear water to simulate the debris which gathers at the bottom of tanks. The suction was strong enough to suck the berries which were close to the inlet of the pipe, however was not very effective when berries were located far away.  A further test was to see if it is possible to use the same outlet to drain the whole tank. This was successful as long as air did not enter the system. It is most likely households would use a hose as a siphon.  Attempted to fix the sealing problem with the pipe fitting the bag was secured to. This was unsuccessful.  Completed a video wrap up of the progress we have made.  Presented all prototypes tested to RWC and made recommendations CP-CBU-125 395

CP-CBU-125 Quotes: Kia: 

“It has been very good to see all your ideas and we thank you for your time”

James Oakley: 

“Your work has been great and even if your recommendations are never implemented in the field, you have got RWC thinking in new ways which might solve a problem in the future”

Further Notes: 

Need to go to the market over the long weekend to try and find suitable tarp for the tarp tank, find chains and find material to replicate the installed bag

J6 – Day 6 Date: 23/09/2012 People: Zac, Jack Activities:  Went to the market to source materials  Found suitable tarps and priced them  Bought chains necessary for the chain filter  Looked for suitable material for bag however could not find anything Quotes: Further Notes:

J7 - Day 7 Date: 25/09/2012 People: Jack Activities:  Visit to RWC office  Took photos of prototypes and documented findings  Discussions with RWC staff on bits and pieces of project CP-CBU-125 396

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Quotes: Further Notes:

J8 - Day 8 Date: 26/09/2012 People: Jack Activities:  Visit to RDIC office  Took photos of prototypes and documented findings  Investigated rope pump availability  Investigated spherical tanks  Investigated option of shipping container with liner as low cost water storage Quotes: Further Notes: Follow up on spherical tanks with contact of Megan’s. J9 - Day 9 Date: 27/09/2012 People: Jack Activities:  Visit to RWC office for last time  Took photos of prototypes and documented findings  Collected remaining prototypes  Video of chain filter  In depth discussion of issues in rural villages, especially getting people to listen  Finalised expenses Quotes: Further Notes: Follow up with RWC in regards to expenses

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Appendix K - Risk Analysis K1 Capstone Project Risk Analysis

Step or sub-task description

Hazards and Risks associated with step or sub-task

At time of travel, Cambodia will be experiencing monsoonal weather

Rain and wet conditions may cause team member(s) to slip and fall

E 10

C 15

L 3

Control Measure

E

C

L

Residual risk rating

450

Wear non-slip shoes and be aware of surroundings (PPE & A)

10

15

1

150

6

15

1

90

Risk Rating

Presence of foreign insects and animals

Allergic reactions

6

15

3

270

Bring required medication and try to stay clear from foreign insects and animals (A)

Contact with places and objects that may be unclean and not sanitised

Bacteria present may cause sickness

10

15

6

900

Wash your hands immediately after contact and apply hand sanitiser

10

15

1

150

10

15

3

450

10

1

0.5

5

Drinking water may be contaminated

Team members becoming sick (stomach ache, diarrhoea)

10

15

6

900

Only drink from sealed bottles of water. Avoid ice and avoid swallowing water when in the shower (E & S)

Visiting a country with a non-speaking English background

Misunderstanding with locals may results in being in a dangerous and compromising situation

10

1

3

30

Be aware of your actions and behaviour

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398

CP-CBU-125 Travel throughout Cambodia on vehicles without seat belts/safety measures

No seat belts may result in horrific consequences if an accident were to occur

Use of a ladder to implement the design prototype at Rainwater Cambodia

Unstable ladder and unpredictable weather conditions may results in a fall

3

25

Modify the prototype at Rainwater Cambodia using their tools and appliances

Different tools with possibly different safety standards may result in faulty appliance that is dangerous to the user (electrical shock)

3

Fumes from pollution

Coughing (and possible further illness) from inhaling the fumes

6

Mosquito stings

Really itchy symptom and possible allergic reaction

Uneven pathways/walkways that are not cemented

Uneven ground may result in tripping

Flying overseas to a foreign country

Staying in a foreign country

Many hazards associated with flying (including malfunction to aircraft and painful blocked ears)

Not have immediate access to (Australian standard) health centres and/or immediate help

Personal Injury

Resulting from recreational activities, being in country

Injury caused from natural disaster

Natural disasters including fire and flooding that result in injuries

6

10

10

3

10

6

2

900

Try to travel on vehicles that are safely equipped (E )

6

50

1

300

3

225

Try to use a stable ladder and ensure that while one person is on the ladder, another is holding it sturdy (E )

3

25

0.5

37.5

25

3

225

Ensure tools are safe to use. Bring own safetytested tools (S)

3

25

0.5

37.5

5

3

90

Cover nose and mouth with hand/mask

6

5

0.5

15

300

Bring required medication and try to stay away from mosquito infected areas (A)

10

5

3

150

450

Wear non-slip shoes and be aware of surroundings (PPE & A)

10

15

1

150

450

Ensure that the flight carrier is reputable and safe, and listen to all instructions (e.g. emergency exits and lifejacket)

3

50

0.5

75

30

Stay in contact with friends and family often, and research health centres that are openly welcome foreigners

10

1

1

10

450

Attend Safety Brief Responsible travel expectations, and requirements on conduct whilst in country

6

15

1

90

100

Have evacuation and emergency response plans in place. Have first aid training and equipment

2

15

1

30

50

5

15

50

1

25

50

3

6

3

3

3

3

1

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399

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Minor personal injury

Due to daily activities in foreign country and different conditions, such as walking around in hot and humid environment

Allergies

Allergic reactions from food, objects, animals

10

10

5

15

6

3

300

Take alternative transport options to walking. All individuals should bring a first aid kit with any personal medication that they require

6

5

3

90

450

Bring medication and be cautious of surroundings, food and animals

10

5

1

50

K2 Endeavour Exhibition Risk Analysis

CP-CBU-125

400

CP-CBU-125

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401

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Appendix L - Scope of Works (As submitted)

Capstone Project Department of Mechanical Engineering

Scope of Works 2012 Project Title: System Date:

Designing the Ultimate Maintenance-Free Rainwater Harvesting 18/3/2012

Project Team: Identifier:

CP–[CBU-125]

Student workers:

Jack Clarke, 356399 Zac Parsons, 359487 Grace Lee, 256089 David Barnes, 359129

Academic supervisor: Colin Burvill Academic examiner:

Colin Burvill

Client Organisation:

Mr Pheng Kea RainWater Cambodia http://www.rainwatercambodia.org/ #11A Street. Lum (02),CPC Village Sangkat Teuk Thla, Khan San Sok, Phnom Penh, CP-CBU-125 402

CP-CBU-125 Kingdom of Cambodia +855 (0)23 630 4030 External Mentor:

James Oakley Engineers Without Borders (WASH Technical Advisor) +855 978489287 [email protected]

Version: #6 (Final), 19/03/2012

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CP-CBU-125 1. Project An important component of a rooftop rainwater collection system is the first flush system, which prevents the initial flow of contaminated water from entering the storage tank. The project is the design of a maintenance free first flush system. RainWater Cambodia is a non-government organisation that focuses on water sanitation in Cambodia. They have implemented a rainwater harvesting system with some success. The major issue with their design is the requirement of manual cleaning/maintenance of the first flush system, which is often neglected.

2.

Objectives

Currently it is the household’s responsibility to clean the first flush system three times a year. Due to lack of education, habits, cultural norms, and lack of knowledge, the relatively simple procedure is generally not being carried out. This results in contaminated water being stored in the harvesting tanks. This project requires the investigation of current rainwater harvesting systems, focusing on the first flush component. Ultimately, the goal is to design a suitable first flush component that requires no manual cleaning. Furthermore, materials should be sourced from Cambodia and the system should be implementable at minimal cost, using appropriate technologies that require minimal knowledge to repair or replace.

3.

Definition of starting point

Cambodia receives a large amount of rainfall, with annual rainfall ranging from up to 5000mm on the south western mountain slopes to 1400mm on the central plains (Encyclopaedia Britannica, 15 th edition). As such, with adequate collection and storage, rainwater can be an excellent source of clean drinking and cooking water throughout the year. RainWater Cambodia has designed a rainwater harvesting system that collects and stores rainwater from roofs via a ‘first flush system’. The purpose of the first flush system is to divert a certain initial amount of “contaminated” water away from the harvesting tanks after a period without rain. This water is considered to be the most “contaminated” as it contains sediments, bird faeces, leaves etc that have accumulated in the gutters and on the roof during the dry season. Rainwater Cambodia’s current first flush system is illustrated in Error! Reference source not found.. After a period without rain, the float chamber is empty. Rain flows directly off the roof into the float chamber until the floating ball seals the entrance, after which rain will flow into the storage tank. Water drains from the float chamber at a slow rate so that after a period of time the contaminated rainwater has completely left the first flush chamber, ready for the next rainfall. The sediment and collected particles have to be cleaned out and emptied at least three times a year.

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Figure 1: The current first flush system in place in Cambodia [PJ Coombes and G Kuczera]

The problem with this system is that it requires regular cleaning to be effective. RainWater Cambodia has found that this cleaning is often neglected, causing debris to build up, blocking the bore pipe, and ultimately resulting in the flow of contaminated water directly into the storage tank. The starting point is to research rainwater harvesting systems already in use around the world, with the focus on the first flush or equivalent cleaning component. The next concern is with designing a new system, selecting appropriate materials, conducting some trials on built prototypes and a cost analysis of the final solution.

4.

Task descriptions

Specific Tasks Tasks towards the completion of the project, in chronological order: 1. Familiarise ourselves with the entire rainwater harvesting system developed by RainWater Cambodia that is currently in place throughout rural Cambodia. 2. Complete a thorough review of the existing rainwater harvesting first flush system. 3. Conduct research into alternative ideas for the first flush system currently in use in other places around the world 4. Meet with and learn from some experts in the area of rainwater harvesting systems 5. Brainstorm and develop some new ideas for the first flush system. 6. Decide on an idea based on cost, effectiveness, resources required and the appropriateness of the technology. 7. Build a prototype model and test it thoroughly. 8. Conduct a cost analysis of the final design. 9. Once an appropriate model is in place and fully tested arrange a visit to Cambodia to conduct a field trial. 10. Review our design based on the results of the field trial. 11. Write the final report. CP-CBU-125 405

CP-CBU-125 Skill Base The skills required for this project are of a less technical nature, primarily research, design and abstract thinking. Creativity and innovation will be required to come up with a simple, elegant solution to the problem. The final product must be simple, in order to be readily implemented, but elegant, to remove or reduce the need for maintenance. The quality of our final product will be directly proportional to these skills as well as our creativity and hard work. The project is practical and very much customer-focused, aiming to deliver tangible results to the customer. Technical expertise can be sought if required from our contacts at Rainwater Cambodia and Engineers Without Borders, as they have been dealing with this technology for a considerable amount of time. Collaboration will be essential. Manufacturing, Laboratory Testing and Equipment All the equipment, tools and laboratory facilities provided by the University of Melbourne should be more than enough to accommodate the projects construction and testing phases. We have additional workshop facilities available at an off campus site should they be required.

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CP-CBU-125 5.Duration of tasks Table 2: Gantt Chart for project, generated using Google spreadsheet

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The Gannt chart is split up int four sections; Dates, Tasks, Inputs and Outputs. The dates include holidays and exams not directly related to the project. Tasks section includes non examinable tasks which will directly impact on our ability to complete the project. This envolves emailing stake holders and organising funding in order to implement the design in Cambodia. The inputs section is for research, design fomation and testing which will contribute to the examinable outputs of the project. The outputs section is dedicated to the examinable reports and final outcomes of the project. 6.

End point

The goal of our project is to provide a working prototype that eliminates the need for manual cleaning of the first flush component of household rainwater harvesting units situated in rural Cambodia. This unit will ideally be cheap and easy to mass produce using the resources available in Cambodia, and the production processes simple enough that it can be taught to locals for long term, sustainable outcomes. The result of this prototype is contaminant free water for households all over rural Cambodia. This will directly increase the quality of life of people living in the area. The non-direct outcome of our research and final product is that by making our findings available others throughout the world may be able to use or build on our designs. There are many developing countries, such as Timor Leste, Nepal and Laos, that have similar water contamination issues and hopefully this projects outcomes will be of use to people from these and other developing countries.

7.

Mentor reviews

Work-in-progress feedback via e-mail every three weeks from us to EWB, and in addition send EWB a copy of each progress report. Participate in EWB Poster Presentation Day, on the 12th of May (presenting problem and initial research/ideas). Assumed key stages for EWB feedback and contribution:    

After brainstorming ideas for the first flush system design (collaboration with the selection process) After initial prototype testing (reporting results, deciding on next action) After final model is in place and fully tested (check that it satisfies EWB’s criteria) During and after field trial in Cambodia (significant assistance and collaboration will be required)

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Appendix M - List of Video and Documents on CD Videos The following lists are of videos included on the CD. Video summaries of RWC’s existing system as well as the Project Team’s work completed are included. The remaining videos are footage of tests. Summary Videos: RWC Existing System Work Completed Summary Test Videos, Cambodia: Angle Test 1 Angle Test 2 Angle Test 3 Angle Test 4 Bag Dirt Bag Test 1 Bag Test Bag Test 3 Bag Test 4 Bag Test 5 Building 2 Building Chlorine Filter First Flush Clogged Twice First Flush Clogged Flow Rate Test RWC Walking Tour Taking Off End Cap Tank Overflow Test 1 Tank Overflow Test 2 Tank Overflow Test 3 Test Rig At Angle 2 Test Rig At Angle 3 Test Rig At Angle Testing Chlorine Filter Test Videos, Melbourne: Ball-Valve Flow Rate Test Overview Ball-Valve Prototype 1, Flow Rate Test 1 Ball-Valve Prototype 1, Flow Rate Test 2 Ball-Valve Prototype 1, Flow Rate Test 3 Ball-Valve Prototype 1, Flow Rate Test 4 Ball-Valve Prototype 1, Flow Rate Test 5 CP-CBU-125 409

CP-CBU-125 Ball-Valve Prototype 1, Flow Rate Test 6 Ball-Valve Prototype 1, Flow Rate Test 7 Ball-Valve Prototype 2, Flow Rate Test 1 Ball-Valve Prototype 2, Flow Rate Test 2 Ball-Valve Prototype 2, Flow Rate Test 3 Ball-Valve Prototype 2, Flow Rate Test 4 Ball-Valve Prototype 2, Flow Rate Test 5 Ball-Valve Prototype 2, Flow Rate Test 6 Ball-Valve Prototype 2, Flow Rate Test 7

Documents The following is a list of documents that were drawn upon in the completion of this project and that will serve as an excellent resource library for further research groups on this project. All the documents below are included in the electronic submission. Appropriate tech catalogue - iDE 2011 Basic water requirements for Human Activities- Meeting Basic Needs - Gleick 1996 Community Water Supply Sanitation Programs Drinking Water Quality Standard - Kingdom of Cambodia 2004 Education opportunities & contraints in teaching Education program in Northern Pakhistan education programme in rural Bangaldesh education programs in africa Effectiveness of Education Interventions First Flush - NZ Food, Water and Health. A manual for community Educators UNDP, WHO 1994 Gender issues for water sanitation projects Guidance on the use of RWH - Cunliffe 1998 Guidelines for water quality WHO 2004 Health and Socio-economic impact of RWH in rural Cambodia Health Impacts in developing Countries Human Development Report UNDP 2006 Impact of RWH on rural Cambodian's McInnis 2008 Implementation Guidelines for RWH - WaterAid bangladesh 2006 Improving Local Service Delivery MDG's in Cambodia UNICEF, UNDP Improving water quality by design - Thomas 2003 Joint Monitoring Program Cambodia - UNICEF 2012 Journal Article of RWH in Nepal - Jane Nichols 2012 Learning how teachers learn in undeveloped countries media_Brochure_Rainwater_Harvesting_First_Flush_Diverter_Range - Aust No Date Problems in water & sanitation in developing countries Progress on drinking water and sanitation - UNICEF 2012 Promotion of Rainwater Harvesting in Cambodia - GRET Quantifying the first flush phenomonon - Martinson 2007 CP-CBU-125 410

CP-CBU-125 Rainfall data in Cambodia 2011 Report Saferain First Flush System - 1966 Roofwater handbook - Thomas 2007 Rope Pump Poster - Wateraid RWC Ferrocement Design Background Report - For Review 210912 - EWB NSW WASH HUB RWC Ferrocement Tank Design Technical Specification - For Review 210912 EWB NSW WASH HUB RWC RWH Installation Manual - English RWC RWH sizing calculations RWC Summary Leaflet RWC Tank cost comparison data RWC Water Safety Plan RWH for poorer households in the tropics - DTU 2002 RWH health socio impact 12-08 RWH in low income countries - Martinson's Thesis 2007 RWH in Nepal - Jane Nichols 2012 RWH in the Caribbean RWH Technical Findings Report 13-12-08 RWH with First Flush in Brazil Safer water better health WHO 2008 Saferain Drawing Sanitation programs in Low Income countries Sealing Code Sew-1313 - Sewage Code of Aust Sizing the first flush and its effect on the storage-reliability-yield behaviour of RWH in Rwanda SODIS Turbidity explained - 2006 Very Low Cost Roofwater Harvesting in East Africa - Thomas 2001 WASH Pictorial Statistics - WaterAid 2011 WASH Stategies by country AusAid 2011 Water quality in RWH in rural and city NSW - Kus et al 2011 Water Safety Plan Process Flow Diagram Water supply, and hygience education Water Technology Notes - WaterAid Wateraid Bangladesh Programme Women's Roles in Sanitation Programs World Water Report - UN 2012 WSP Study for safe wter access in arsenic affected communities in rural Cambodia

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Appendix N – Grants and Awards

Appendix N1 Vice Chancellor’s Engagement Awards 2011 Extract “The Vice-Chancellor’s Engagement Awards recognise the work the staff and students at The University of Melbourne carry out with the wider community. Knowledge partnerships and engagement activities with business, government, not-for-profit organisations and community groups lead to innovative programs that benefit both the University and its partners, with outcomes that could not have been achieved alone. Engagement activities enable the growth and use of knowledge, consistent with the University’s public-spirited character. These partnerships are intricately dependent on the University’s research and teaching and learning activities and contribute to the achievement of the University’s overall mission.”

N2 Dreamlarge Student Engagement Grants 2012 Website Extract “The Dreamlarge Student Engagement Grants 2012 aim to:  broaden student experiences during their education with The University of Melbourne  assist and promote the development of engagement projects between students of the University and external organisations  enable students to apply their learning in projects which develop skills and leadership while improving the economic, social, environmental or cultural life of our region locally, nationally or internationally. Grants will normally be to a maximum of $2,500. However, six grants will be awarded for amounts up to $5,000, including the Melbourne University Credit Union (MUCU) Dreamlarge Student Engagement Grant. Projects should commence no later than the end of Semester 1, 2013, and be completed within a year of commencement.”

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N3 Dreamlarge Application

The University of Melbourne

DREAMLARGE - STUDENT ENGAGEMENT GRANTS 2012 APPLICATION FORM Applicants are advised to read the Guidelines for Applicants (located at the end of this form) containing the scheme and the selection process before completing this form.

Applications close Friday 25 May 2012. 

A hard copy of this application form must be lodged with the Melbourne Engagement and Partnerships Office: 201 Grattan Street, University of Melbourne, 3010.



A soft copy of this application form with all supporting documentation (Word [email protected].

Please enter all name/contact details correctly as this information will be used to on successful certificates/trophies. Team Leaders are to double-check application forms with project team members.

SECTION A – PROJECT DETAILS PROJECT TITLE Title of project

Designing the Ultimate Maintenance-Free Rainwater Harvesting System PROJECT LEADER (PLEASE USE BLOCK LETTERS) Title

Mr

First Name

ZACHARY

Course

MASTERS OF ENGINEERING (MECHANICAL)

Phone(s)

+61437007156

Email

[email protected]

Student No.

359487

City where you grew up*

MELBOURNE, AUSTRALIA

Surname

PARSONS

*This helps publicise your program in relevant media

DETAILS OF OTHER PROJECT TEAM MEMBERS (Please note: there must be a minimum of 3 currently-enrolled University of Melbourne student team members – including the project leader.) Title

MR

First Name

JACK

Surname

Course

BACHELOR OF ENGINEERING (MECHANICAL)

Phone(s)

+61407202271

Email

[email protected]

413

CLARKE

Student No.

356399

City where you grew up*

MELBOURNE, AUSTRALIA

*This helps publicise your program in relevant media

DETAILS OF OTHER PROJECT TEAM MEMBERS (Add extra names, where there are more than 3 team members.) Title

MS

First Name

GRACE

Course

BACHELOR OF ENGINEERING (MECHANICAL)

Phone(s)

+61403157428

Email

[email protected]

Student No.

256089

City where you grew up*

PERTH, AUSTRALIA

Surname

LEE

Surname

BARNES

*This helps publicise your program in relevant media DETAILS OF OTHER PROJECT TEAM MEMBERS (Add extra names, where there are more than 3 team members.) Title

Mr

First Name

DAVID

Course

BACHELOR OF ENGINEERING (MECHANICAL)

Phone(s)

+61403157428

Email

[email protected]

Student No.

359129

City where you grew up*

MELBOURNE, AUSTRALIA

PROJECT OVERVIEW Amount applied for

$5,000

Proposed date for commencement of the project in 2012/13 Proposed date of completion

28 FEBRUARY 2012 2 NOVEMBER 2012

Has this project previously received a Dreamlarge Student Grant?  Yes X No If you answered yes, what is new about the current project, and how does it build upon the previous project? N/A

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Project Summary We are a team of four Mechanical Engineering students completing a final year Project (subject code:MCEN90022), in conjunction with two external non-profit organisations: Engineers Without Boarders (EWB) and Rain Water Cambodia (RWC), to develop a maintenance free rainwater harvesting system. The design must be innovative, utilising appropriate technology to harvest rainwater for Cambodian households at an affordable cost. The harvested water must meet World Health Organisation (WHO) current drinking water guidelines. The project will address social, economic, environmental and cultural issues The Central Intelligence Agency website states that only 56% of the rural population of Cambodia has access to improved drinking water. Drinking unimproved water can lead to diarrhoea as well as a host of water born diseases. As of 2009 diarrhoea is the second leading cause for death in children under five, killing 1.5million infants annually around the world. A maintenance free rainwater harvesting system can be successfully designed and implemented, that produces safe drinking water, using appropriate technology, at an affordable cost to rural households. The system has the ability to dramatically reduce infant mortality rates in Cambodia. Furthermore, if proven to work appropriately, the technology could be implemented more widely in communities with similar needs. The project is innovative Rainwater harvesting systems are already implemented in Cambodia and South East Asia. The system we are designing will not have substantive impediments that plague current designs. One main focus, although not the only aspect, of our design will be to improve the first flush subsystem. Currently the first flush system diverts an initial quantity of water carrying organic matter collected on the roof, guttering and piping into a down pipe. Once the down pipe is full, the drinkable water then flows into a catchment. The problem is that there is a build up of organic material at the bottom of the pipe that requires cleaning. The cleaning is not currently being performed, clogging up the downpipe and rendering it useless. The outcome is that undrinkable water is being captured. One main design consideration is to develop a robust, cheap, and appropriate first flush that does not require cleaning. This will increase the reliability of the system as a whole. The two other major considerations of our research are the optimisation of the current system and education of the community. The project will benefit the external partner EWB has a strong background in sustainable development through engineering in Cambodia. Their partnership with undergraduate research teams is consistent with their ethos to foster academic involvement in their operations. Our commitment to EWB greatly benefits the organisation through having extra volunteers dedicated to sustainable engineering development, obtaining a tangible outcome and increased media coverage. The overarching objective of their initiatives is to ensure that all projects will have tangible benefits to the affected community. The key to this is fostering a relationship based on understanding, mutual appreciation of the issues faced in implementing new processes in communities, cultural awareness and personal interaction. Based on these criteria our ability to travel to the community will have a significant bearing on the success of our project and the development of our team as leaders, global citizens and humanitarian engineers. The relationship between EWB and The University of Melbourne is relatively new, but with successful projects such as the 2011 Tonle Sap biodigester project, it is rapidly becoming a strong and mutually beneficial relationship. The project will benefit The University of Melbourne by contributing to the student team members’ development as leaders in the community and as active global citizens The greatest portion of our grant request will assist us to travel to Cambodia in September 2012. To implement our most effective solution, it is essential for our project team to engage directly with the local community, source materials there and test the acceptance of the device in the local community. While in Cambodia, we will collaborate with the EWB in-country volunteer and Rain Water Cambodia to maximise the opportunity for our proposed solution to be embraced by the community, both culturally and practically. Our learning experience as student engineers will be significantly enriched by this unique opportunity.

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SECTION B – PROJECT SUPPORT PROJECT MENTOR (For information about project mentors, see Guidelines for Applicants at end of this application form.) Title

DR

Surname

BURVILL

First Name

COLIN

School/Faculty

DEPARTMENT OF MECHANICAL ENGINEERING

Contact at partner organisation: Oakley First Name

James

Phone(s) Email

[email protected]

SECTION C – EXTERNAL PARTNER DETAILS PARTNER ORGANISATION CONTACT Partner organisation (Add extra names and signatures, where there are multiple partners.) Name of Partner Organisation

Engineers Without Boarders

Title

Mr

Surname

Position

Technical Advisor

Phone(s)

+855 (0)978489287

Email

[email protected]

Please note that partner organisations may be asked to complete a brief feedback survey (5 min) on this program.

SECTION D – OTHER FUNDING AND PROJECT BUDGET Specify other funding received for this project: Source

Amount

From EWB and RWC (In Kind)

$5,100*

Students

$3,484*

*See budget for details

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SECTION E – ENDORSEMENTS PROJECT LEADER The proposed project has been developed in consultation with the partner organisation. I confirm that the project budget has been reviewed by the project mentor and/or a member of the Faculty Business Centre. I confirm that the project team has addressed any risks relating to:  working with children under 18  research involving human participants  environmental health and safety issues, for instance dangerous chemicals, working with animals, or other hazards  travelling outside Australia  Intellectual Property (IP) which students may wish to protect  any other risks identified while developing project. ZACHARY PARSONS Name

Signature

PROJECT MENTOR I support the proposed project, and confirm that I have reviewed this application for a Dreamlarge Student Project Grant and have addressed any risks relating to:  working with children under 18  research involving human participants  environmental health and safety issues, for instance dangerous chemicals, working with animals, or other hazards  travelling outside Australia  Intellectual Property (IP) which students may wish to protect  any other risks identified while developing project. I undertake to continue providing advice to the student team until conclusion of the project. COLIN BURVILL Name

Signature

AUTHORISED PARTNER ORGANISATION CONTACT (Attach letter of endorsement from the partner organisation)

I support the proposed project and confirm the financial and/or in-kind support of our organisation (as detailed in Section C – Project Budget). I understand I will be asked to provide feedback on this program (no longer than 5 min) after project conclusion.

JAMES OAKLEY Name

Signature

417

The University of Melbourne

DREAMLARGE - STUDENT ENGAGEMENT GRANTS 2012 GUIDELINES FOR APPLICANTS PURPOSE OF SCHEME The Dreamlarge Student Engagement Grant Scheme supports engagement projects which connect student groups with external partners. Grants will normally be to a maximum of $2,500. However, six grants will be awarded for amounts up to $5,000, including the Melbourne University Credit Union (MUCU) Dreamlarge Student Engagement Grant. The Scheme is designed to broaden student experiences during their education with the University of Melbourne, assist and promote the development of engagement projects between students of the University and external organisations, and enable students to apply their learning in projects which develop skills and leadership while improving the economic, social, environmental or cultural life of our region locally, nationally or internationally. Summaries of successful projects to the 2011 scheme can be viewed at www.mepo.unimelb.edu.au APPLICATION PROCESS  Applications must be made on the official application form and include all supporting documentation.  Applications close on Friday 25 May 2012. Late applications will not be accepted.  A signed hard copy of the application as well as a soft copy is required. The hard copy should be forwarded to: Melbourne Engagement and Partnerships Office 201 Grattan Street University of Melbourne Vic 3010 The electronic copy should be forwarded to: [email protected] NOTIFICATION OF RESULTS and AWARD PRESENTATIONS Applicants will be notified of the result of their application by the end of August.  Grants and award monies will be paid into a nominated Themis accounts during September.  The Vice-Chancellor’s presentation of awards will be held in September.

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CONDITIONS OF AWARD  Details of the partner organisation’s agreement and financial or in-kind support must be provided.  Each team awarded a grant is required to provide a brief report on the project, signed by all participants, by 28 February 2013. If the project is not completed, an update on progress should be submitted. The report will be completed in a format specified by the Melbourne Engagement and Partnerships Office – you will receive an email update closer to the due date.  The Melbourne Engagement and Partnerships Office will use project information for promotional purposes. STUDENT ELIGIBILITY  Applicants must be students currently enrolled in a course offered by The University of Melbourne and must complete the project before they complete the course for which they are enrolled.  Where the team consists of students from more than one Faculty, the application must be lodged with the Faculty in which the team leader is enrolled. PROJECT ELIGIBILITY  The project must commence no later than the end of Semester 1, 2013, and be completed within a year of commencement of the project.  Each team must have a minimum number of three members, including the team leader.  Projects must have the support of a non-academic partner organisation (mentors will assist students to find a partner organisation, see below).  Partner organisations must match the University’s contribution. The contribution made by the external partner may be cash or ‘in kind’ support for the project. ‘In kind’ support includes resources, materials or staff time that are essential to the project.  Projects must have a significant engagement dimension  For projects involving secondary schools, preference will be given to those partnering underrepresented schools. For a list of these schools, go to: http://www.futurestudents.unimelb.edu.au/ugrad/accessmelb/underrep.html FACULTY MENTORS  The project leader is advised to contact a Faculty leader to discuss finding a mentor for the project. (Each project must have a mentor, who signs off on the application.)  See the Melbourne Engagement and Partnerships website for list of current Faculty leaders at http://www.mepo.unimelb.edu.au/content/pages/faqs SELECTION CRITERIA FOR ELIGIBLE PROJECTS  The project will benefit the external partner.  The project will benefit The University of Melbourne by contributing to the student team members’ development as leaders in the community and as active global citizens.  The project will address social, economic, environmental or cultural issues.  The project is innovative. With the establishment of the University’s formal engagement with Timor Leste, we welcome any applications with a focus on Timor Leste.

419

N4 Budget for Dreamlarge Application

420

N5 EWB Letter of Endorsement for Dreamlarge Application

421

N6 Dreamlarge Application Letter of Success

422

N7 Sustainability Award Application (As submitted)

423

Project Overview The majority of people in rural Cambodia live using a variety of sub-standard water sources, which put them at risk to a myriad of illnesses. Villagers must travel great distances and expend large amounts of time and effort to obtain the sub-standard water. One solution practised by locals is RainWater Harvesting (RWH). There is a clear need for sustainable water access solutions in rural Cambodia and the monsoonal climate fosters the ability to utilise RWH efficiently, such that it is the most appropriate technology. RainWater Cambodia (RWC) is a Non-Government Organisation (NGO) operating in Cambodia and managed by Cambodians. RWC focuses on RWH in rural Cambodia with the overarching principle of reducing risk to the recipients of the implemented systems. RWC has a well-established RWH model that they assist communities to purchase, understand and install. However, the RWH system has a number of areas where sustainability could be improved. The project aim was to optimise these areas. The current RWH system issues outlined by RWC are included in Table 1 (all tables and figures are located in the attached appendix). The team won a Dreamlarge grant from the Vice Chancellor in order to work with RWC in Cambodia for two weeks. The team presented multiple recommendations to RWC at the completion of the trip. The key sustainability recommendations covered included:  Cost  Materials used  Efficiency of collecting water  Quality of water stored Proposed Sustainability Improvements First Flush System The aim of a first flush system is to redirect an initial amount of water away from the storage tank. This water carries organic matter collected on the roof, guttering and piping system. The current system is shown in Figure 1 and 2. There are three main parameters in a first flush system: 1. Volume of water flushed during an initial rainfall event – set by volume of the downpipe 2. Reset time – the time it takes the first flush to empty when a rain event stops 3. Flow rate while full – how much water comes out in the middle of a rain event The volume of water to be flushed is well documented and the team did not make any recommendations to change this. Much less research exists in the areas of reset time and flow rate when full. These two parameters are a function of the pressure head of the first flush system and the size of the bore hole. In Cambodia the team used the services of a translator from RWC to interview a range of stake holders including families, health centres and school administrators. The villagers interviewed in the fieldwork highlighted that too much water was being wasted from the first flush system. In response to these concerns, the team ran tests on the current system to determine the flow rate and reset time. The team then used two innovative methods to slow the flow rate when full and increase the reset time, reducing the water wasted.

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The first method was to change the pressure head by angling the pipe, seen in Figure 3. The second innovation was to use a semi porous bag to replace the bore hole at the bottom of the first flush, seen in Figure 4. The cost of water for villages in Cambodia was determined with a cost analysis using an existing formula. The interviews conducted, along with discussions from professionals at RWC, provided the team with information about the locals’ water habits. The relevant information used in our CAPEX is summarised in Table 6.The next step was to use rainwater data, as seen in Table 5, to calculate the hours per year that it rains and the amount of water ‘wasted’ by the first flush system emptying at the end of each rain event. This is shown in Table 7. The other source of wasted water is that which is continuously streaming out of the bottom of the first flush while it is raining, which is governed by the flow rate when full. Therefore, the total volume of water wasted each year by the first flush is the sum of water wasted while raining and water flushed at the end of a rain event. Using the value of water calculated in Table 6, the total annual value of water wasted was calculated, shown in Table 8. This table compares the existing system with the innovative angled system and bag prototype. It is shown that the advancement of angling the first flush can save 50% in the cost of wasted water, while the bag prototype can save over 90%. The porous bag has the lowest flow rate and highest reset time, while maintaining the volume of water flushed. Tank Design Initial capital costs typically make up the majority of the overall expenditure for RWH systems. The storage tank is the largest contributing factor to the start up costs of a RWH system. Currently RWC implement two different types of tanks in households and institutions. Part of the group’s field research in Cambodia was to survey local markets in order to cost alternative tanks. The costs of the current tanks, seen in Figure 5 are summarised in Table 2. The aim of the alternative tanks was to increase the amount of water that could be stored and to decrease the cost of the tanks used. A summary of alternative tanks can be seen in Table 3. It can be shown that the Tarpaulin Tank, seen in Figure 6, is the most cost efficient medium sized tank (between 3000L and 6000L). The Tarpaulin Tank is 83% more cost efficient than the tanks already in use and requires no cement. A CAPEX of the Tarpaulin Tank can be seen in Table 4. The largest tank researched was the Partially Below Ground Tank, which has a relatively attractive cost per litre including labour, whilst being able to be scaled up to very large volumes. This tank is nearly 100% bigger than the any other tank available for a similar cost per litre including labour. The new tank designs cut down on cement and water used, reducing the impact on the environment, the cost to the owner whilst increasing the ability to store water. Tank Overflow When the tank becomes full in the current system, the water in the top of the tank overflows onto the ground. Theory states that the cleanest water in a tank is located at the top, therefore the current systems removes the cleanest water when the tank is full. A separate issue in the current system is that there are leaking cleaning valves at the base of the large tanks, shown in Figure 7. Initial research into best practice for seals of this type found that a hydrophilic sealant was normally used. Discussions with an industry professional came to the same conclusions. Unfortunately hydrophilic sealants are unavailable in Cambodia, so the Project Team was required to think creatively in solving this issue. The project team came up with an innovative solution which can solve both issues while reducing materials used and reducing associated costs of replacing the valves.

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The new design, seen in Figure 8, combines the cleaning valves and the overflow pipe into one, minimising costs. The seal is now located at the top of the tank, reducing the water pressure on the PVC-cement bond to only a few centimetres of pressure head. As the water gets higher than the top of the pipe, a change in head causes water from the bottom of the tank to be sucked out, cleaning the sludge from the base of the tank automatically. If the tank needs to be drained, a hose can be attached and a siphon effect is created to start the suction. The tank will drain for as long as the hose outlet is below the water level in the tank. Summary The proposed solutions achieve savings in cost and materials used while increasing the volume and quality of water stored. The ring tanks currently last ten years, so a comparison of the CAPEX is completed over a ten year period. Table 9 compares the CAPEX of the current system to the proposed systems over this 10 year period. The greatest savings are indirect from a reduced cost due to wasted water with the proposed first flush designs. The direct savings come from the proposed Tarpaulin Tank. It is estimated that the tarpaulin tank only has a life span of 5 years; however it is still cheaper to build two tarpaulin tanks over a 10 year period than one concrete ring tank. The total estimated savings over 10 years are $487.88 for the angled first flush with the tarpaulin tank and $802.76 for the bag prototype with the tarpaulin tank; a saving of 9% and 15% respectively of the average Cambodian wage. A secure and sustainable water source is possible for rural Cambodia.

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Tables and Figures Optimising Rainwater Harvesting in Cambodia

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Table 1: RWH system issues identified by Rainwater Cambodia Issues Identified by Rainwater Cambodia The lack of maintenance of the RWH systems from stakeholders The high upfront cost of the systems installation The lack of knowledge and understanding of drinking water quality, hygienic practices and the health risks involved The failure or poor performance of particular RWH system components (such as the leaf filters, tank seals and first flush system)

Table 2: Cost Summary of Existing Tanks

Cost/L w Labour

Tank

L

Cost

Cost/L

Jumbo Jar

3000

$ 111.70

$

0.022

$

0.037

Concrete Ring Tank

3000

$ 117.12

$

0.024

$

0.039

Table 3: Cost Summary of Alternative Tanks

Tank

L

Cost

Tarpaulin Tank 5000 $ 60.14 $ Single Skin External Reinforced 6000 $ 160.51 $ Underground Brick Dome Tank 5000 $ 173.80 $ Jumbo Jar 3000 $ 116.82 $ Pumpkin Tank 5000 $ 131.86 $ Concrete Ring Tank 3000 $ 213.12 $ Partially Below Ground Tank 10800 $ 433.85 $ Brick Jar 3000 $ 126.82 $ Mortar Jar 1000 $ 85.50 $ Ferro-Cement Jar 3000 $ 126.82 $

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Cost/L 0.006 0.017 0.015 0.024 0.017 0.056 0.023 0.027 0.026 0.027

Cost/L w Labour Rating $ 0.012 $ 0.027 $ 0.035 $ 0.039 $ 0.026 $ 0.071 $ 0.040 $ 0.042 $ 0.086 $ 0.042

10 8 9 6 2 4 5 1 3 1

Table 4: CAPEX of proposed Tarpaulin Tank Materials

Quantity Wood m Mud/clay m3 Tarpaulin 5*6 # Wire Kg galv sheet m2 Drainage System: 21mm diameter # Pump # Labor Unskilled Days Skilled Days

Litres

Units 30 0 9 1 3 2 7

5000

5 10

Cost/Unit 0.26 1 1 2 0.78 1 1 2 2

$10.00 $20.00 Final Cost $60.14 Cost per L $0.0060 Cost per L W Labour $0.0120

Table 5: Monthly Rainfall Events in Phnom Penh, Cambodia

Month

Rain Events

January

2.8

February

2.4

March

5.2

April

8.6

May

16.4

June

16.6

July

19.6

August

21.4

September

19.8

October

24

November

11.8

December

4.8

Total

153.4

429

Total Cost $7.80 $0.00 $9.00 $2.00 $2.34 $2.00 $7.00

Table 6: Cost of Water to Average Villager in Cambodia

Quantity

Units/day

Units/year

Distance to water

Hours

2

730

Wage of unskilled labourer

$USD/Hour $

0.63

$ 0.63

Value used for villager

$USD/Hour $

0.31

$ 0.31

Water collected

Litres

200

Cost of water

$USD/Litre

$

0.003

Total cost for average family

$USD

$

0.63

73000

Table 7: Rainfall per year Amount of rain (days/year)

153.4

Average time per rainy day (Hours/day)

1.5

Time per year it rains (Hours/year)

230.1

Rain events in a rainy day (#/day)

2

Rain events in a year (#/year)

308

Flush after rain event (L)

10

Total Flushed after rain events (L/year)

3080

430

$ 0.003 $ 228.13

Table 8: CAPEX: Evaluation of the Cost of Wasted Water from the Existing System Compared to Proposed Systems

Angle (Degrees) Height difference (m) Test 1 (Hr) Test 2 (Hr) Test 3 (Hr) Flow Rate While Raining(L/Hr) Hourly Waste of Water Whilst Raining ($USD/Hr) Flush per Hour of Rain(L/year) Yearly Waste of Water Whilst Raining ($USD/year) Total Flush Water Emptied Per Year (L/year) Total Wasted Emptying Flush Water Per Year ($USD/year) Cost of Wasted Water per Year($USD/year)

Existing System 0 0 0.015 0.0153 0.0153

0 0 0.019

15 0.16 0.019

30 0.31 0.022

45 0.44 0.024

60 18.31 0.032

Bag Prorotype 75 0 18.16 0 0.045 1

98.36

78.26

78.26

68.35

62.79

46.55

33.54

Angled System

$ 0.307 $ 0.245 $ 0.245 $ 0.214 $ 0.196 $ 0.145

$0.105 $ 0.005

22632.79 18007.83 18007.83 15728.35 14448.14 10711.55 7717.64 $ 70.73 $ 56.27 $ 56.27 $ 49.15 $ 45.15 $ 33.47 3080

3080

3080

3080

3080

$ 9.63

$ 9.63

$ 9.63

$ 9.63

$ 9.63

3080

431

$24.12

345.15 $

3080

$ 9.63 $ 9.63

$ 80.35 $ 65.90 $ 65.90 $ 58.78 $ 54.78 $ 43.10

1.50

$33.74

1.08 1534

$

4.79

$

5.87

Table 9: Comparison of CAPEX Between RWC Current System and the Project Teams Proposed Systems Over Ten Years

System Fixed Costs Roofing Piping Screens Guttering Sub Total First Flush Materials Replacing Parts Annual Waste of Water Cost of Wasted Water Sub Total Tank (300L) Materials Labour Replacing Tank Sub Total TOTAL

RWC System $ $ $ $ $

19.50 8.00 3.00 3.45 33.95 Straight Down Pipe $ 16.78 $ 80.35 $ 803.52 $ 820.30 Concrete Ring Tank $ 168.12 $ 45.00 $ 213.12 $ 1,067.38

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Proposed Systems $ $ $ $ $

19.50 8.00 3.00 3.45 33.95 Angle Down Pipe $ 20.34 $ 33.74 $ 337.43 $ 357.77 Tarpaulin Tank $ 18.08 $ 30.00 $ 48.08 $ 96.16 $ 487.88

$ $ $ $ $

19.50 8.00 3.00 3.45 33.95 Bag Prototype $ 25.78 $ 50.00 $ 5.87 $ 58.72 $ 134.50 Tarpaulin Tank $ 18.08 $ 30.00 $ 48.08 $ 96.16 $ 264.62

Figure 1: Schematic of Current First Flush System

Figure 2: Current First Flush Installed in Cambodia

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Figure 3: Test Rig the Project Team Built to Test Flow Rates at Different Angles

Figure 4: The Project Team and Mr Van from RWC staff, next to the Innovative Bag Prototype

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Figure 5: Current Tanks in Use – Concrete Ring Tank (Left) and Jumbo Jar(Right)

Figure 6: Tarpaulin Tank - The Most Promising Alternative Tank the Team Built

435

Figure 7: Leaking Cleaning Valves at the Base of Current Tanks

Overflow Berries sucked from bottom of test tank

Drainage Figure 8: Testing the new Tank Overflow with Berries at the Bottom of the Tank

436