Read our water safety tips to learn how to be prepared for a fun adventure while swimming in national parks! Wear a life jacket - It is important to wear a properly fitted, U.S. Coast Guard approved life jacket at all times when recreating in open natural water, even when boating. Lifeguards are not present at all national park swimming areas. Being a strong swimmer does not guarantee that you will not drown; in many cases it is this false sense of security that has placed visitors in dangerous circumstances. Search and Rescue teams may take time to reach you depending on your location. Swimming in strong currents or even treading water can tire you out quickly. A properly fitted life jacket can help you float while you wait for help.