When is the most dangerous time to cross a coastal bar

Crossing surf bars is a common but extremely dangerous part of boating along the New South Wales coast.  Every year boats are damaged and people killed or injured when attempted crossings go wrong. Nothing that is written here can make crossing a bar completely safe.  This is a general guide only.

It is  mandatory for all persons in a recreational vessel to wear a PFD Type 1 when crossing a bar. The entrance to Brisbane Water is an official ocean bar. (to see Maritime Authority Website related to wearing lifejacket click here)

The most important points are stop, look and think.  Skippers who are not 100% certain of their safety should not go.  No feed of fish or day at sea is worth risking the boat or people’s lives.

Bar Basics

The movement of sand along the coast and sediment from catchments builds up bars at the entrances to estuarys, rivers and lakes. The dynamic forces of wave action and water movement change the shape, depth and channels on the bar quite regularly.

A big storm may deepen it by a metre or more or a long season of on-shore breezes may build the bar by the same amount. A strong out flowing tide provides more drag on an incoming swell and forces it to be steeply faced, higher and more inclined to close out or dump.

The wind direction can also be a factor in setting up both waves on the bar and angling the swell at different directions onto the bar. The channels in the bar are cut by tidal movement and do change from time to time.

Local knowledge

Local knowledge is an essential part of crossing any bar.  Every bar is different and all bars can change quickly depending on the conditions. The following points need attention before crossing any bar:

• If you are new to an area, observe the bar from land first. If possible use Polaroid type sunglasses to pick the visible channels indicated by darker coloured water and lack of breaking waves
• Talk with the locals or check with the nearest NSW Maritime Boating Service Officer, Marine Rescue unit or marina owner
• Watch how other vessels handle the bar.  Take note of the line they follow in and out, where they wait and watch and where they move off to cross the bar
• Take careful note of any navigation aids that may help, particularly leads that mark the channel.

Preparation

After gaining a working knowledge of the bar check the weather forecast and most importantly the state of the tide at the time you want to leave port. An incoming tide is always safer. If possible time your day at sea to coincide with a rising tide both leaving and entering port.

Check that your boat is operating correctly and make sure throttle and steering systems are perfect.  Check the battery and fuel tank are locked down or fixed in place. Ensure your safety gear is in good shape and a PFD is available and properly fitted to each person on board.

On the water procedure

• Warm up the engine and check everything is running smoothly.  Do not attempt the crossing if the motor is misfiring or does not respond quickly
• Check the steering and bilge pump
• Close all hatches
• Secure the anchor(s).  Do not leave it sitting in a forward well where it could become a lethal missile or be catapulted overboard
• Arrange passengers so that the boat is balanced and secure all gear
• Each person must be wearing a properly fitted PFD of appropriate size (nb children must wear children’s size PFDs, not adult size).
• With the bar in sight, idle around and check the conditions.  Then decide to proceed.

Going out

When heading out, remember you will experience a clash of very severe forces.  The outgoing boat must meet the energy of the breaking sea, minimising these clashes makes things safer for you and the boat.  The main technique is:

• Idle towards the breaking waves watching carefully for any lulls.  If a flat period occurs apply the throttle and run through
• If the waves just keep rolling in, motor to the surf zone and gently accelerate over the first piece of white water, then apply more power and run to the next wave.  Time this carefully, don’t go too fast or you may get airborne on the next wave
• Back off the power just before contact with the swell.  As you come through or over the breaker accelerate again and repeat the process until clear
• Head for the lowest part of the wave (the saddle).  This is the last part of the wave to break
• As an alternative, half cabin vessels can proceed slowly through the entire bar system, although at some stage a wave will break over the boat.  So long as the boat goes straight ahead, very little can happen to it.

Don’t

• Don’t hit a wave face with the power full on, the boat can become air borne or throw the crew into the windscreen, dashboard or floor;
• Don’t lose your nerve.  Once committed, keep going forward.  You may be swamped if you try to turn around at the last moment;
• Don’t go through waves at an angle.  Either go straight or up to 10 degrees either side of dead straight.

Coming in

Coming in over the bar is usually easier.  However, once you are mixed up in the white water the noise and boisterous seas can test your nerve. When entering the bar move towards the breaking area and pick the line of least activity.  Stay with the leads or channel markers if the breakers obscure your vision. Watch for breakers that may form to seaward of your observation point.

Once you have the general direction, wait for a big set to roll in and position the boat on the back of a wave and stay there.  Don’t run down the wave face. Very little can happen if you hold your position.

As you approach the actual entrance, the outgoing tide may affect the boat’s speed.  Maintain power and trim the nose of the boat up a little, adding power as needed. The outrunning tide may also create pressure waves near the mouth of the system.  These steep peaks should be handled carefully as they can destabilise the craft causing it to yaw or broach.  Handle pressure waves by accelerating gently as you come over each wave.

Remember that everyone must wear a personal flotation device (PFD) when crossing the bar.

General information

• Always check the weather before leaving port
• Make sure you know of any alternative ports or safe anchorage areas before heading out.  If the bar becomes impossible to cross make sure you are carrying enough fuel to reach that alternative location
• Alcohol and boating are a dangerous combination at any time.  The problems of crossing a bar demand a clear head from all on board
• Most bars or bar areas have radio coverage available on the 27 MHz (Ch 88)and VHF (Ch 16).  Marine Rescue Bas stations can provide bar information, sea conditions, weather forecasts and tidal data.  Using the radio base adds to your safety particularly as you can call before and after crossing to ensure that someone knows you are on the bar and organise assistance should it be needed
• Make sure you understand the capacity of your boat to handle breaking seas.  Some boats are not designed for the job
• Most importantly, the skipper should have both the experience and temperament to handle the situation.  If you are new to boating only cross bars in good conditions and gain experience gradually.