TRAVERSE CITY (AP) – Authorities were trying to determine what caused weekend flooding along a river near Traverse City, where those affected remained under a health advisory Monday.
Saturday’s flood beneath Brown Bridge dam resulted from failures apparently connected to a station that was to gradually release water from Brown Bridge pond. It was expected to take more than two weeks, but the pond emptied in four to five hours.
Grand Traverse County health officials said water from flooded wells is unsafe unless boiled properly.
The 28-mile-long Boardman River flows into Lake Michigan at Traverse City. The Brown Bridge dam is the first among three dams to be removed to return the river to its natural flow.
Sandra Sroonian, an engineer who works with the river’s restoration group, said inspections and other tests will be needed to determine the cause of the flooding. She is senior principal engineer for AMEC, an engineering firm hired by Traverse City to oversee the removal of Brown Bridge Dam and its pond.
Sroonian said bridge inspection, reopening roads, downstream reconnaissance and sediment monitoring are the major tasks that must now be tackled.
Bridge inspectors from the Michigan Department of Transportation and private consulting engineers also completed inspections to determine whether flooding damaged Garfield Bridge just south of River Road.
The river is believed to have crested at Beitner Road Bridge about 11:30 p.m. Saturday at 4.5 to 5 feet above normal levels, county officials said in a release.
Downstream from Brown Bridge Dam, flooded homeowner Dave Hoyt said the Boardman River ran through his property sometime after 8 p.m. Saturday, forcing them to evacuate about 90 minutes later. Hoyt said the river “barreled” over a small bridge in front of his house and into his front yard. The river carried with it everything from docks to trees, he said.
“It was like whitewater when it washed over the road. I stepped off the back step of my house and I was in water up to here,” Hoyt told the Traverse City Record-Eagle, pointing to a thigh-high spot on his jeans. “My wife cried.”
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