Entering a Barred River By Doug Brooker “Touchwood” If in doubt – STAY OUT!!! Entering or exiting a barred river entrance is an exercise which should always be approached with caution. However, if you cruise the East Australian coast and do not enter the rivers, you are missing out on some great cruising. The waterways behind the bars are each unique. They vary from the huge calm expanse of Lake Macquarie, to Southport and the inland waterways to Moreton Bay or the amazing 35 mile trip up the Clarence River to Grafton. To arrive by yacht at an inland town such as Innisfail, in a yacht, always seems to be sort of cheating.

There are only three sorts of bars - Dangerous, Very Dangerous, and Bloody Dangerous. No reason is good enough for you to attempt a crossing if you think it is not safe. A rough night bouncing round at sea is preferable to wiping out on the end of a breakwater or rolling your boat over!! However, if approached with appropriate caution and some knowledge, barred entrances can be crossed in safety. On approaching the entrance, pause and take a good look at the conditions. Runabouts are no help as they can enter across a badly breaking bar by sitting on the back of a wave. A displacement boat does not have that luxury. Several waves will always pass a yacht before she gets into calm water.

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Most modern yachts are good at surfing down following seas. Some of the older style, long keel yachts with small rudders are not as good. Once they make up their minds to broach, it is hard to convince them to go in a different direction. If your boat is hard to steer in big following seas, she will not be as able to cope with poor conditions crossing a bar as a boat which is better behaved when hard running at sea. When leaving port, if things are at all rough, it makes sense to wait back from the entrance for a while to check that conditions will stay passable until you are well clear of the shallow water around the entrance. A few preparations are essential before leaving on a trip, especially if you are anticipating some bar crossings. Sludge in the fuel tanks will be stirred up in rough water, and will quite easily stop the motor. This is guaranteed to happen at the worst possible moment. Boats have been lost through having dirty fuel tanks. The auxiliary motor must be large enough to keep the boat going even if she hits a wave when heading out over a bar, and also must give you sufficient performance to make headway against the current if you intend to go upstream. When actually crossing the bar, open the throttle wide to ensure that you get past the bad bit as quickly as possible, and to maintain plenty of steerage way. Obviously, the motor should have been checked over to ensure it is in good order and completely reliable. Your steering will be subjected to unusual, extra strains, especially if you are thrown around by a rogue wave. Before departure, your rudder and steering gear should be properly checked out. I know of one yacht which was lost when she broached on a bar because the rudder skeg broke off. This left the stock unsupported, and it bent 30 degrees, rendering the rudder useless. With no steering, the boat broached beam on to the seas, rolled over and sank. In NSW it is compulsory for everyone aboard to wear a lifejacket when crossing a bar. While this regulation was obviously made for runabouts, it makes sense. In addition, on a yacht everyone should wear safety harnesses so that if a person falls overboard, they will be kept with the boat. Certainly, if you are in doubt as to whether it is safe, you must not attempt a crossing. This is a harder decision than it first appears. For instance, your friends may have crossed safely a little ahead of your arrival, but their boat may be better at surfing than yours, or the current may have become adverse since their arrival. Your crew are certainly ready for a quiet night in smooth water, and it is a hard decision to doom them to another night at sea. But you must remember, boats are seldom damaged out at sea, while broaching into a breakwater is guaranteed to make a mess of your pride & joy. Once you have committed to crossing the bar, and are approaching the entrance, you must not change your mind. If you keep straight on the wave, you should be able to enter safely. Trying to turn and head back out is a really bad idea. Night crossings are also not the best idea as you are less able to confirm whether the conditions are safe or not. One of the main concerns when planning a bar crossing is the current. If it is running out it will cause the incoming swell to stand up. This is due to the collision between the energy contained in the water running out and the energy of the waves rolling in. When the current reverses and starts to run in, there is no collision of forces, and the whole area calms down. The difference is dramatic. 2

Probably the best way to understand when the current will change is to consider Lake Macquarie. This is a large lake with a narrow, shallow entrance channel, and its height hardly varies with the tide. Outside, the ocean moves up & down about 1.5 metres. When the ocean is up at high tide, it is above the lake. The water in the channel runs downhill to the lake, so the current runs in. At low tide, the ocean is below the lake and the current runs out. At half tide, the ocean is level with the lake, so the current stops and then reverses at about 3 hours after the time of high or low tide (See sketch). This is called over run.

The same principle applies to rivers, but the size of a river influences the time that the current will change. There is obviously a lot of water leaving a big river like the Clarence, so the ebbing current will not turn until later. In addition, if it has been raining heavily upstream, it can get to the stage where a river can run out all day and night. The stream may slacken off a little near high tide, but then again it may not. A flooded river combined with bad onshore weather or a large swell can make a river entrance quite impassible until conditions change.

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Unfortunately, the local marine rescue service probably doesn=t understand the concept of over run. Asking them when the current changes may have them reading the time of low or high tide from the printed tide tables, which of course you already know. One has to be careful relying on the reputation of a place. For instance, Port Macquarie doesn’t have a good name, and before the north breakwater was built in 1976, it had no defined channel and was a very bad entrance. Since that time it is deep and straightforward, and is no worse than many other places.

In contrast, Ballina faces south east with no protection. It deserves its bad name and should be treated with respect. Once, we were waiting off Ballina for the current to change. The entrance was breaking right across, but a trawler came out anyway. When they were just clear of the southern breakwater, a wave broke clean over the top of their wheelhouse. 45 minutes later, after the current had started to run in, we entered with the waves well under a metre, and no sign of them breaking in the channel. Perpendicular Point protects Camden Haven from the South. This protection is a great help, although in bad weather, swells can break all across the bay under the headland.

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Some bars have their own funny quirks. In the entrance to Lake Macquarie, the ocean bar is coal and quite shallow. If your boat is deep enough to sit on the bottom in a trough, it is a memorable experience. At most ports, leads have been set up to show the best water across the bar. Even if an entrance looks bad as you approach from the side, on the line of the leads the channel may be smooth. Each side of the channel, there will often be breaking waves, but this is not of concern even though it looks scary. You must always look and satisfy yourself that you are happy to enter. The channel may have changed since the leads were last realigned. At Mooloolaba, sand can build up across the entrance from the east. This may be marked by a cardinal mark but it also may not be marked. Entering the Clarence River, unless it has flooded recently, the leads will take you right across a shallow bank some distance outside the entrance. Normally, at this entrance, one should only get on the leads quite close in. For specific information on the various entrances right along the East Coast, Alan Lucas=s books are invaluable. He even has free updates available on the internet. It is tempting to follow another boat across a bar. After all, if they think it is safe, it takes some of the responsibility off you. Wrong!! The safety of your boat is totally your responsibility. In addition, you don=t know what their boat is like, or how good their helmsman is. You must make your own decision. By now most of you are probably scared out of your wits, and you are swearing you will never attempt a barred entrance. But that would be a pity. The marine weather forecasts always mention the sea state. Put all the available information together, then plan your passage to ensure you arrive in reasonable conditions and when the current is running in. If you do this, bar crossings are really not a problem.

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One last thing - As you approach an entrance from out at sea, there will inevitably be some people standing on the breakwaters, staring at you. You are already concerned about entering, so the natural reaction is for you to assume these people know something that you don=t. The reality is that they are on holiday in the area, they are bored out of their minds, and a yacht coming across the bar and entering the river is the most exciting thing that has happened for days. Of course they are watching you, but they certainly don=t know anything to concern you.

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