Wednesday, June 5, 2013

Surf Safety:  Rip Currents


Written June 3, 2013, photos by Kathleen Sayce and Doug Knutsen

Our beaches are visitor friendly, with wide soft sands and a gentle slope from dunes to the tide zone, but the surf zone can be deadly. The surf zone has a complex structure in summer, with layers of sand bars and channels, as many as four or five rows of sand bars. Because of the bars, there are also numerous rip currents, strong west flowing currents that run between the ends of sand bars, fed by water in the channels behind each sand bar. This structure can be seen at low tide, and is almost completely obscured at high tide. The currents are still there and flowing fast even when covered with water. 

From the air, the beach looks placid; however, a series of rip currents are active all along this summer beach. Photo by Kathleen Sayce

Where Rip Currents Form

Learn where rip currents are likely to form and what they look like:  A spot in the surf line where the break is delayed a few seconds, or where foam or brown water (with sand in it) moves seaward as waves move landward indicates a gap in sand bars; the water may also be smoother in these gaps. 

Rip currents flow seaward at one to eight feet per second, or three to five mph. They are typically 30-50 feet wide and can be more than 120 feet wide. Rips flow seaward up to 2,500 ft before completely dissipating. They can be fixed in position, or move hundreds of feet along the beach over a few hours. Beaches with several layers of sand bars tend to have the strongest rip currents––like our beach. Under optimal conditions, a rip current can form every few hundred feet along a beach, as the aerial photograph shows. 

Rip currents are hard to see at beach level, but the breaks in sand bars are not. There's a strong rip between these two sand bars. Photo by Doug Knutsen. 

Safety:  Swim parallel to the Beach

I don’t know a swimmer in the world who can swim against a rip current and win. Know what to do in a rip:  Call for help immediately. Swim parallel to the beach, across the current, until you are out of it. Then swim back to shore. 

The first line of safety is to not enter the water in the first place. If you must go in the water, find quiet back channels and pools behind sand bars. Stay away from the gaps between bars.  In the surf, don’t wade more than knee deep. Strong currents and sneaker waves are less likely to surprise you, or knock you down, in shallow water. 

Many visitors in past years who drowned on our beaches were caught in either a deep back channel behind a sand bar, or in rip currents between sand bars. They panicked, were disoriented, and fought the current. 

In or near the water, stay oriented. Never turn your back on the surf. Know where you are on the beach, and where you entered the water. The next wave could be a sneaker, a much larger wave that runs up hundreds of feet higher on the beach, and knocks down everyone in its path.  If you aren’t watching, you won’t know when it hits, and when you come up, you won’t know where you are. You can be knee deep in water one moment, and waist deep or knocked down the next.  Be very watchful of small children near the water. It’s easy for them to be knocked down by small waves. 

If jumping waves, watch the longshore flow and your position on the beach. Longshore currents can move you from the middle of a sand bar to an end in a few minutes. With the next jump, you go off the bar and into deeper water in the rip. 

Don’t swim near jetties, rocks or piers, where there are fixed rip currents. There’s a rip current off the end of the north jetty at Cape Disappointment State Park where water blasts seaward along the north side of the jetty. Fishing Rocks at Beard’s Hollow also has fixed rip currents; this is a very dangerous area to enter the water because the currents make it impossible to get ashore. Doug Knutzen, South Pacific County Technical Rescue, told me that when the surf rescue team goes in the water between Fishing Rocks and Benson Beach for a rescue, they swim out to meet a Coast Guard boat rather than try to swim ashore due to the strong rips in this area. 

If you must swim, swim with a buddy; never swim alone. Wear a float vest or wet suit to add another layer of safety in or near the water. Either one will keep you at the surface in an emergency, so you can focus on swimming instead of staying at the surface and breathing. 

The red arrows mark the location of rip currents on one stretch of beach, less than a mile, in summer. Note the complex structure, with bars and lagoons, as well as rips. The long-shore current is moving from lower right to upper left, or north to south. Aerial photo by Kathleen Sayce


The tide is always flooding or ebbing on the beach. A flood (rising or incoming) tide is especially dangerous on a sand bar. The channel you waded through to get to the bar when it was two feet deep may be five or six feet deep when you go back. Study it before you enter the water going back to shore. If a current is flowing, move to the middle of the bar and cross there, well away from stronger currents towards each end. 

Pets are vulnerable too

Pets also drown in the surf.  If you are tossing sticks in the water for your dog to retrieve, avoid likely rip current areas and back channels with strong currents. If your dog is caught in a rip current, move up or down the beach away from the current, and call your dog to swim to you. This will encourage the dog to swim out of the current. When the surf is high, keep your dog out of the water.  Dogs are naturally strong swimmers, and more buoyant than humans, but sending them into high surf and rip currents is pushing their abilities to the limit. 

For more information, check the NOAA website online at  HYPERLINK http://www.ripcurrents.noaa.gov/" http://www.ripcurrents.noaa.gov/, which has photos and diagrams about the formation of rip currents, safety tips, surf advisories, and links to other sites. 


South Pacific County Technical Rescue posts photos, video clips about rip currents, and safety tips for beach, surf and cliff safety, at  HYPERLINK "https://www.facebook.com/spctrescue" https://www.facebook.com/spctrescue

Doug Knutzen, SPCTR, drove the beach with me to talk about rip currents, sand bar structure, and beach safety. 

Be smart, know the signs of rip currents, and be safe, even on hot days at the beach.  


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