Thanks for your post. When you say you have encountered them in the water, do you mean the ocean? I didn't think they would go into salt water.
Have you ever seen them on the beach during the day? I would use caution but I have heard stories of them coiling up under a chaise lounge chair, getting in a sleeping bag, etc.
Would be be better off camping where there are more people? What about if we camped at a regular camp ground, are they also known to be there too?
Sorry for so many questions but I am not used to even have to think about snakes and their behaviors.