June 2010 Table of Contents |
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What to do if Caught in a Current When you can’t beat them – join them. Go with the flow. Don’t out swim it, outsmart it. Whichever tagline grabs you, use it. The important thing is to remember not to fight the current. A rip or channel current will not pull you under. Anyone who has felt the pull of a rip current knows that keeping a cool head and going with the flow is counter to all instinct. But that, say experts, is exactly what you should do. These tips will also serve you well when swimming in the ocean. You can escape it
Coming Up As more information is available on channel currents, Michigan Sea Grant will make it available. Here is what is planned for 2010-2011:
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Tuning in to the Hazards of the Great Lakes Experts have noticed a different type of current hazard – channeling In the Great Lakes, swimmers don’t have to worry about scraping against the razor’s edge of coral, rapidly changing tides or sharks. But the seemingly innocent lakes do present a different cadre of hazards. Michigan Sea Grant Extension Educator Ron Kinnunen and Dave Guenther with NOAA’s National Weather Service have been working for the past eight years to bring one of the greatest Great Lakes dangers to light: rip currents. Kinnunen and Guenther have once again teamed up to educate swimmers and boaters about a particular kind of water danger. Channeling the Current But the phenomenon at Picnic Rocks on Lake Superior isn’t exactly a rip current. Kinnunen said Picnic Rocks is an area ripe for what he and Guenther refer to as channeling. Guenther explained what that means. “What’s happening is we have a channel current moving parallel to shore, flowing between the beach and an island,” said Guenther. “The presence of a tombolo – which is a partially submerged sandbar connector between the mainland and the offshore island – causes a convergence of flow that causes the water to speed up as it goes through the area. It’s like a river running parallel to shore, the current can be that strong.” The danger, said Guenther is when people are swimming in the area or using that sandbar as a means of transport. People walk or swim along the sandbar to get to the island and back to the mainland. “What happens then, when the winds pick up a little bit, that will make the waves pick up and will increase the current speeds,” explained Guenther. “When that happens, they can get pushed off the sandbar or swept into colder water on either side of the sandbar. Essentially then the swimmer panics and tries to get back to the ‘safety’ of the sandbar. The cold water and the current eventually exhaust them.” When that happens the swimmer is usually fighting directly against the current. It’s not a matter of strength. Guenther said Olympic-level athletes have been swept off the sandbar and couldn’t successfully fight the current. “There are at least 11 drownings in the last 40 years that we can attribute to this channel current effect,” he said. “There really hasn’t been much documentation on it yet.” Elsewhere “The danger occurs when the wind amplifies these currents in a confined area, such as between the shore and a close, offshore island,” he said. A similar effect can be created with man-made structures, making docks, underwater structures and piers susceptible to strong and changing currents. Other natural areas in the Upper Peninsula where these channel currents become dangerous can be found at Round Island located just south of Escanaba, Hog’s Island near Naubinway, Saddlebag Island near Detour. In those three areas there have been drowning incidents that mirror the drownings at Picnic Rocks. There are potentially many more areas that will be identified as susceptible to channeling as awareness about the phenomenon is spread. As Kinnunen explained, the key elements are an island close to shore in combination with wind and current flowing in a certain direction. The presence of a sandbar can funnel the water through the area that much quicker. The sandbar also often makes the area more appealing to swimmers, which increases the traffic and exposes more people to the possible danger. Escape and Survive It helps to think of the current as a river. A swimmer will likely have a better chance of swimming across a river, cutting through the current or by riding with the current until the water calms down. The most inefficient and dangerous thing to do is try to swim against the current. “Those caught in a channel current need to swim toward shore and should not try to swim back to the sandbar in panic as in most cases they will not be able to make progress against this current,” Kinnunen said. Improving the Odds With funding from the Great Lakes Observing System, Northern Michigan University students are working on an acoustical Doppler system forecasting buoy project for Picnic Rocks. The buoy would record certain data that specialists know contribute to the longshore currents that cause channeling. With the collected data, they could issue real-time forecasts that keep people out of the water. It would operate similar to the rip current beach forecast systems around the Great Lakes. The channel current forecasts could begin in July. Also, said Guenther, beaches without lifeguards could be stocked with emergency equipment boxes. “Often when we hear about drownings, it’s not the person who was originally in trouble who has drowned,” he said. “Every year there are stories about how someone went into the water to help someone else and they are the ones who end up victims.” “The emergency boxes, the warning system and education about how to remain calm and how to appropriately respond to getting caught up in a current are the most effective things we can do for now,” he said. See: > Next
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