No, God never lets bad things happen. He only allows bad things to happen. When He allows it, there will always be a reason. Every single time. The Bible also says that he will never let you face a trial that you(with Gods help) can't handle.
Depends on the ocean and the activity, you will hurt your health;
ex:touch something infect you will ve infected.
Nothing but do you want to be known as the guy who doesn't wash his hands
That's gross. Wash your hands.