Why You Should Train in Shallow Water

“But it's so difficult here! The water is only ten feet deep!” It seems that I hear this from about fifty percent of my cave diving students. We train basic cave skills in the open water area of cenotes, where the depth tends to max out at about fifteen feet and we do the skills hovering neutrally buoyant mid-water. The truth is, that pretty much every type of control is more difficult in shallow water, and that is precisely why shallow water makes for such an incredible practice environment – if you can control yourself in shallow water, you can control yourself anywhere.

So grab your fins and head out to the shallow end of the smallest pool you can find, here are five things that you can improve by practicing your diving skill in shallow water.

Buoyancy

Air in a diver's BCD expands and compresses as he moves vertically in the water. What is interesting is that it expands/compresses more per a foot in shallow water than it does in deeper water, because the greatest pressure change is near the surface. For example, if a diver descends to 10 meters, the air in his BCD compresses by half. If he descends from 10 meters to 20 meters, the air in his BCD only compresses by a third.

If you extrapolate this to very shallow water, it is obvious why controlling your buoyancy in very shallow water is so difficult: the changes are much greater than those at deeper depths commonly experienced by recreational divers. Controlling your buoyancy in shallow water requires fine tuning – half compressions of the inflation button to allow only the faintest whisper of air to enter the BCD and gentle deflations to let only a few bubbles out.

Learn to hone your buoyancy using your lungs and BCD in shallow water, and I guarantee that buoyancy control at twelve meters will be a breeze.

Kicking Techniques

Shallow water environments, particularly pools, are great for learning your shape and size in the water, and for fine-tuning your kicks, such as the frog kick. No matter what kicking technique you use, being constrained by hard floor (that you can't damage) and surface will help you learn to control your fin movements by keeping your fins more-or-less behind your body, as opposed to below or above it. Imagine that each time you touch a wall, the surface, or the floor, that you just contacted a coral, and learn to position your body and move your feet in a way that does not impact the environment.

Better control of the fins also leads to more effective propulsion and less wasted movements, helping to reduce a diver's underwater exertion and air consumption.

Breathing Techniques

If you hyperventilate, hold your breath, or exhale to fully in shallow water, you will immediately feel the effect on your buoyancy. Shallow water is great for practicing relaxed, consistant breathing techniques because it gives a diver instant feedback. Learn to breath rhythmically and calmly. Find a lung volume that holds you at the level you desire, then inhale slowly until you just barely start to move upwards. Then, exhale calmly back to neutral lung volume and then past it until you just barely start to sink. Then inhale back to neutral lung volume again. Experiment with the depth and timing of breathing cycles until you find one that allows you to gently rise and fall within only a few feet, returning to your starting depth at the end of each cycle. Not only will this calm your breathing during diving, it will improve your buoyancy and awareness of stress. Want an extra challenge? Try clearing your mask or other skills mid-water without losing buoyancy by keeping your breathing cycle consistent, even while you are performing the task.

Positioning

Have you ever seen a diver just hang in the water, motionless? The ability to be absolutely still underwater is extremely useful during safety stops and underwater photography, or even when just watching a fish. Finding a fixed point in a shallow water environment – such as a specific tile in a pool – and then attempting to hover motionless will help you to evaluate how much you actually move underwater. Most divers find they move a great deal. It's hard to stay still in shallow water, and it's hard to avoid bumping into pool walls, the floor, or the surface, but attempting stillness will allow you to evaluate the trim of your gear and your unconscious movements, correcting them until you can hover like a fish.

Gear Evaluation

Shallow, relatively confined spaces are a great place to evaluate your gear. Do you find your pressure gauge scraping against the pool floor? You may need to change where you attach it to your BCD. Do you notice that your feet keep hitting the surface? Your trim is probably off and you may want to adjust your gear to hold you more horizontally in the water. And of course, whenever you are diving with new gear or gear that you haven't used in a while, shallow water is a great place to evaluate its condition. If you have a problem you can just stand up.

I know two general types of divers who practice in pools - and they are at different ends of the diving skill spectrum: students and top-notch technical divers.  Tec divers practice in pools because it makes them better, for all the reasons listed above. Diving in pools or very shallow dive site for practice may seem boring or even be frustrating, but if you challenge yourself to improve your buoyancy, propulsion, breathing, equipment configuration, and positioning, and hour in a pool can just fly by. Once you get these basics down, try to practice skills such as air sharing and mask clearing in the water to increase the difficulty or your pool session. It's good practice, and on your next dive trip you will notice that your practice in a ten-foot pool made you more comfortable and controlled and controlled on an eighty-foot dive.