Getting in and out of the sea
So many questions to think about and knowing the answers to them is the key to safe sea swimming conduct.
Before you enter the water ask yourself the following;
What is the tide doing here exactly?
What will the tide do to the water current? How soon before or after the time of the local high or low tide does the current slow? This is in relation to where the shoreline is and also the lunar variation of the tidal range that day.
What will the tide do to the waves? This is reliant on knowing the shore, its gradient and the dynamic movement over time of sand/pebble banks. Turning tides ‘on the push’ in can also help swell on to the shore increasing height.
How quickly will I not be able to stand and jump the waves? This depends on the wave size, gradient of the shore and also currents of water generated by the breaking waves. It also depends on your height, strength and the surface that you’re be wading on.
Are there ‘Rip Currents’? and am I avoiding them or using them to help me clear the breaking waves?
Am I going to try and clear the breaking waves by swimming out to sea? If not will I only breath on the same side in each direction (every 2 or 4 strokes). This I think is an important part of planning your route. Have a plan A route and a Plan B route if the conditions are worse than you calculate. It’s easier to plan exits when you are warm, dry and easily breathing.
What is the swell period? A large swell with a period greater than 10 seconds makes it possible to breath both sides and only breath on the beach side simultaneously when required/desired.
Will I need to dive each time a wave is passing me by? Some sizes of waves that are ‘standing up’ as they approach shallower water, or have ‘white water’ over a size that you recognise (if not then learn which size carefully) will need to be negotiated. Swimming through them (perpendicular of parallel) is achievable but this will break the fluidity of your swimming and potentially expose you more to current movement. This increases the chances of you staying in the same spot, or moving backwards. If it’s a large size I would only advice swimming through them perpendicular to the direction of the wave.
Where am I planning to enter the water? This decision should be based on the shore gradient, what is down current (can you safely exit there is needed), will people be able to see me, are there bigger waves further out to sea (from a bank)? Is the a boat lane I want to avoid? Is there an object or known submerged obstacles I need to avoid?
Where am I planning to exit the water? It may be the same location you enter. This is because you may ‘turn around’ on your planned route, or recognise that the swim will be neutralising the current and you won’t be moving along the shore. Bear in mind that with the tide change (and the time you are planning to be in the sea) that the current strength may change.
What is inland from the shore that I will be able to sea from the sea? It is so important to look inland and memorise landmarks. With these you can assess your progress (or deviation) on your route, and also evaluate distance to shore.
I’M GOING IN THE SEA
Make sure you’ve answered all the questions above. They only takes a few minutes of reading, looking and talking.
Is it safe to go in the sea? Do not dive in the deep end just because you think you should, others are or you feel you won’t look the part. When it comes to negotiating surf I have a huge amount of respect for people who say no. Jumping off rocks and jetties may save a lot of hassle, but if you can’t swim out, I feel it’s not safe to go out.
Steep shore gradient, chest high waves and mobile peddles to stand on. I think it is so important to recognise that the safe place to be is either stood on the shore, or be in deeper water away from the breaking waves. The middle ground before those two locations should be approached with care and correct timing. Care involves being ready to dive through the waves and swim out to sea at every opportunity. On steep gradient shorelines that distance isn’t far.
The timing is tricky to learn and understand.
The first thing that I have to say is that waves aren’t organised. Struggling to learn fluid dynamics taught me that at least. Wind pushes the surface of water and the wind generates ripples. These ripples are more exposed to wind and the generate more energy from the wind. The further distance these waves travel the more they amalgamate and we often will see swells that have travelled the globe (called ground well) amalgamate into groups of 12-14. Often the middle wave is the biggest. The key thing to know though is multi-faceted. More than one swell is often running at the same time. Because of different speeds they can overlap and cause bigger waves. Wind swell is locally generated and often is quicker as it hasn’t had the time and distance to amalgamate. A wind swell that is quick (less seconds) is harder to analyse and if there are overlapping swells of different lengths (in seconds) and directions they can become a mess to evaluate.
All that said though, watch the waves breaking on the shore. When you see the biggest waves coming in walk towards it. As soo as you see the one behind, if it doesn’t look bigger then carefully wade into the water with bend knees and a slightly wider gait. At this point you are entering to middle ground. You can either turn around and immediately return to dry land or swim through the waves out to sea. Do not stand in the middle ground as you will struggle to stay there with any control. Do not enter the middle ground with anyone close to you if anybody is surfing the wave in your direction.
Standing on the shore it can be hard to determine how big the waves are. Counting the seconds it takes for the lip to hit the water is a good indicator. To learn what size is associated with timing comes with experience. Bear in mind that the wind direction and strength can adjust the speed. When the waves breaks does the water water continue to travel down the wave face? This indicates that the wind is blowing towards the shore.
the waves usually appear to accelerate and decelerate when they have broken. If they don’t appear to then I spend time assessing what I’m looking at. Have I missed something? The fluctuating speed can be explained with pressure changes.
The image below shows the pressures generated by a breaking wave. Although this is a steep wave, the same happens with less variance in the pressures generated. If you time your dive (therefore you need to be moving forward) correctly with the low pressures you can ‘pop’ through the wave with surprising ease. The high pressures can detonate you in any direction like a rag doll.
When you enter and exit the sea it is really useful to time it with the breaking waves. Diving down into the water timed with the lower pressure area is extremely productive.
Entering or exiting the sea should include concentration on where the waves are going to break and attempting to predict where the pressure areas will be located. You can only do your best!
