For whatever reason, Having your EDC or rifle in trunk of your car, parked just across the beach should be good enough. Otherwise, carry as usual and do not swim. You would the sentry for your swimming party.
No Psychic is needed, but how many beach goers do carry? Isn't supposed to have EMT and lifeguards and local LEO patrol the beach?
If an area feels not safe, bail out and find a safer area.