Great Lakes swimmers: Beware of potentially deadly rip currents

University of Michigan Health System
Thursday, 20 May 2004

Rip currents in the Great Lakes are a deadly but largely unknown phenomena, and the University of Michigan, through the Michigan Sea Grant College Program, has joined a national campaign to educate the public about the potentially fatal waters.

People often associate rip currents—channel currents that can sweep them from shore—with oceans, said Donald Scavia, professor in the School of Natural Resources and Environment (SNRE), and director of Michigan Sea Grant, a joint program between the University of Michigan and Michigan State University. It is administered through the School of Natural Resources and Environment at U-M.

In the past two years, at least 18 people have drowned in the Great Lakes, and experts believe a majority of these deaths probably happened because people panicked when a rip current pulled them from shore. Nationally, lifeguards rescue approximately 60,000 people from drowning a year, and an estimated 80 percent are caused by rip currents. Additionally, an estimated 100 people drown from rip currents annually—more people than are killed by tornadoes or lightning, Scavia said.

Rip currents form when waves break near shore, piling up water between breaking waves and the beach.

"If the beach is set up just right, the water comes up on the shore and it will collect and shoot out in a small underwater river…that underwater river is in fact the rip current," Scavia said. "Rip channels can be as much as 10 to 20 feet across, and move at speeds a little slower than you can run but faster than just about anybody can swim."

That means it's impossible to out-swim a rip current by swimming against it, he said.

"The most important thing is that if you get caught up in a rip current, simply relax and float, then swim parallel to the shore. It's easy to swim out of a rip current but not up against it," Scavia said. Visualize getting off a treadmill that you cannot turn off, but that you must exit by stepping off to either side.

Rip currents are tough for the layperson to recognize but subtle signs exist, such as: a channel of churning, choppy water; an area of different color; debris moving steadily offshore; or a break in the incoming wave pattern.

Michigan Sea Grant, in collaboration with National Oceanic and Atmospheric Administration's (NOAA) National Sea Grant, NOAA-National Weather Service and the United States Lifesaving Association, has developed brochures and beach signs warning people of rip currents and how to escape them. Those graphics will be unveiled at a news conference on Monday, (May 24) 10-11 a.m. at the Holiday Inn Sunspree Resort in Wrightsville Beach, N.C. For more information about this event, contact Ben Sherman at (301) 713-3066 ext. 178.

New rip current brochures are available by contacting Michigan Sea Grant at (734) 764-1118, . A design template for the production of beach signs is available for use by community organizations interested in water safety, visit for details.

For more information, or to contact University of Michigan Health System, see their website at:

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