When are whirlpools in the water really dangerous and what to do if you encounter one?

Whirlpools are among the most treacherous dangers in the summer season when we take a refreshing dip in oceans, lakes, and even rivers. They are water vortexes created by the convergence of two opposing currents, resulting in about 400 drownings each year. Currents are usually caused by winds, the nature of the seabed, and temperature fluctuations, while whirlpools mainly form in lakes and rivers. Whirlpools can also be created by sea storms and strong winds that lift the water body and generate currents. Moreover, the risk of drowning in freshwater rivers and reservoirs is even greater due to sudden water depth and the lack of salt that helps the body stay afloat. The funnel effect that creates the whirlpool is further intensified by the Coriolis force in lakes, which is associated with the Earth's rotation. In some reservoirs, whirlpools can also be artificially created to prevent the lakes from overflowing. The Berryessa Reservoir in Napa, California, is famous for the several meters deep whirlpool that formed there. If you encounter a whirlpool, it is important to remain calm and not panic. It is crucial not to try to swim to the shore to counteract it, as one would instinctively do. Instead, it is advisable to swim parallel to the shore or stay upright and swim underwater where the current is less strong, and only then swim to the side to get out of the whirlpool.