RED FLAGS:
Our beaches employ a warning system -- a large red flag flying indicates that the currents are strong and the water is unsafe for swimming. DO NOT GO IN THE WATER -- YOU PUT YOURSELF AND LIFEGUARDS AT RISK! Local safety officials determine when such conditions exist and also make the decision as to when to take the flags down. Conditions may change during the course of the day -- pay attention! Just because red flags are not posted does not mean the ocean is safe; there is always a risk when swimming or wading in open waters. If you are concerned about the conditions, check with a lifeguard at one of the designated lifeguard stands.
RIP CURRENTS:
Strong rip currents can start very near the beach and carry you into deep water in seconds. They're caused by a slight depression in the beach between breaking waves; the returning water will head for the depression and soon become a dangerously strong seaward flow.
Rips can also be caused by a set or drift being turned seaward by a pier, jetty, or protrusion of land. A rip may be narrow at its source -- anywhere from a few feet to 15 to 20 yards --- and it doesn't travel as far as a runout. Usually a rip begins to dissipate a few yards beyond the breaker, but that can be as much as 1,0000 feet from shore.
The visual evidence of a rip is similar to that of a run out; at streak of turbulent discolored water or a line of foam running directly away from the beach. If you are caught in a rip, do not try to swim straight back to shore. Swim parallel to the shore until you feel the current weaken, or let the current take you out until it weakens. Then swim to shore at a 45 degree angle.
UNDERTOW / BACKWASH:
Water thrown up onto the beach and then speeding back to sea, aided by gravity is known as undertow. The person who knows enough to not resist will be carried outward for a few feet towards deeper water. Then, as the next wave breaks, the undertow will cease, and he will be carried toward the shore by the next incoming wave. If the swimmer resists, she risks having the next wave crash down of her, perhaps causing injury.
If you misjudge a wave and you find yourself being tumbled in a mass of froth and sand, do not obey your instinct to struggle up to the surface. Relax, go limp in a curled up position, and let the wave toss you up on the beach or let the undertow carry you out into calmer water where you can then swim to the surface.