HOLLAND, Mich. — National Weather Service and Michigan Technological University researchers are trying to find ways to better predict when Great Lakes beaches will generate offshore currents that have claimed dozens of lives in recent years.
Rip currents are particularly common on Lake Michigan, where the find sand makes underwater sandbars vulnerable to washouts that can allow the outflowing of water.
Authorities at Holland State Park in western Michigan had to pull 28 people from the water on Aug. 3, 2011, after currents along the pier dragged swimmers away from the Lake Michigan shore.
"We've had bad days before, but this was like one of those perfect storms," Rick Bierlein, a state park officer, told The Detroit News (http://bit.ly/12bkGXB ). "We had a northerly wind, it was hot and people wanted to swim."
Rip currents are most common when winds are blowing toward shore, causing water to pile up. Researchers say the outflowing water can puncture sandbars, pulling swimmers into deeper waters.
Michigan Tech and weather service researchers are using a variety of tools to see how near-shore currents form and behave in an effort to make the dangerous areas safer for the public.
Guy Meadows, director of Michigan Tech's Great Lakes Research Center, is using new tools to decipher the riddles of rip currents and long-shore currents, which run parallel to beaches. The goal is to create an early-warning system that identifies the factors that lead to dangerous currents and gives swimmers the kind of information that might save lives, he said.
"The ultimate goal is to be able to accurately predict the presence of dangerous near-shore currents and, on any given day, to know where they will be prevalent and where they won't," Meadows said.
Michigan Tech researchers are using a special radar developed at the university's research institute in Ann Arbor to track how waves move toward a beach. They are also using satellite technology to map the bottom of Lake Michigan near shore in certain areas to provide a baseline of information ahead of trouble events.
So far, researchers have found that Lake Michigan by far has the largest number of drownings and current-related incidents, human-made structures such as piers and break-walls generate the currents that cause the most incidents and 72 percent of incidents occur when winds are blowing toward shore.
Besides wind and weather conditions, bad judgment plays a key role in rip currents accidents and deaths, one expert says.
"The unfortunate reality is people do some dumb stuff," said Bob Pratt, executive director of education with the Great Lakes Surf Rescue Project, a nonprofit group dedicated to reducing drowning deaths.