Rip currents are powerful, channeled currents of water flowing quickly away from the shore. They are the leading cause of rescues at beaches globally. These currents are not “undertows” that pull swimmers down, but strong, narrow rivers of water moving rapidly offshore through the surf zone. Recognizing the signs of a rip current before entering the water can reduce the risk of becoming caught. This article details four visual cues to help you identify a rip current from the safety of the sand.
The Core Visual Indicators
A telling sign of a rip current is a noticeable gap in the pattern of incoming breaking waves. Waves typically break uniformly along a sandbar, but the outgoing flow disrupts this process, creating a section of water that appears flat or calm amid the surrounding whitewater. This absence of breaking waves marks the path of the strongest offshore flow.
A second, highly visible indicator is a channel of churning or choppy water that looks distinct from the smoother surface nearby. This turbulence occurs because the fast-moving water in the current violently interacts with the incoming waves and the seabed. The water in this area often appears discolored, which is the third major clue.
The current’s speed and force scour the ocean floor, pulling sand and sediment away from the beach. This action causes the water within the rip current channel to look murky, cloudy, or darker than the clearer water flanking it.
Finally, look for debris moving steadily seaward. Observable objects like foam, seaweed, or small pieces of trash will be carried rapidly away from the shore in a concentrated stream against the general direction of the waves.
Identifying Formation Zones
Rip currents are fueled by water that piles up near the shore from continuous breaking waves, seeking the path of least resistance to flow back out to sea. These currents commonly form where there is a break or a low spot in a nearshore sandbar, creating a deep channel for the water to rush through.
They also frequently occur adjacent to fixed, artificial structures that interrupt the natural flow of water along the shore. Jetties, piers, and groynes cause water to accumulate and then be funneled into a narrow channel right next to the structure. These structurally-controlled rip currents can be persistent and may occur even when the waves are not particularly large.
Beaches with heavy surf or strong wave action are more prone to rip currents, as the energy of the breaking waves contributes to the strong offshore flow.
Immediate Action if Caught
Despite careful observation, a swimmer may still get caught in the powerful, offshore pull of a rip current. The most important initial step is to remain calm and resist the instinct to panic. Do not attempt to swim directly against the current toward the shore, as the current’s speed can exceed eight feet per second, which is faster than an Olympic swimmer.
Instead of fighting the current, swim parallel to the shoreline to exit the narrow flow of the rip. Most rip currents are relatively narrow, often less than 80 feet wide, so a short swim sideways can move you out of the main current. Once you feel the current weaken, you can then swim back to the beach at an angle away from the original rip location.
If you are unable to swim out of the current, the safer alternative is to float or tread water. A rip current will eventually dissipate just beyond the line of breaking waves, allowing you to float until the current loses its strength. While floating, signal for help by raising an arm and yelling.