Our ocean is 50 degrees. This is important because your body has to make specific adaptations when regularly exposed to water temperatures below 77 degrees. People who often swim in water this cold may retain some subcutaneous body fat to protect themselves, and their blood vessels may retard heat transfer to the skin. Our bodies are so neat. If you don't know how, or don't do it well, contact a teacher in town.
Swimming is great exercise.
You can do it forever. It is kind to the body and comforting to the soul. Enjoy the water, but respect it. Always swim with a buddy.