The Boardman River, above the old Brown Bridge Dam site, stands out against the snow-covered land. |
at a number of places over the years. The Department of Natural Resources has been working with other entities to remove or modify those dams to restore the Boardman, which flows through Grand Traverse and Kalkaska counties, to a more natural state.
The impoundment behind Brown Bridge Dam was drawn down before the dam was removed. |
that span multiple jurisdictional boundaries. The project actively engages local, state, federal and tribal units of government, as well as non-profit environmental groups, educational institutions, stakeholders and the general public.
Four dams, all within 20 miles of the mouth of the Boardman, where it empties into West Grand Traverse Bay, came into focus for this project. Union Street Dam is about a mile upstream from the river mouth. Five miles further upstream sits Sabin Dam. Another mile upstream is Boardman Dam. And 12 miles upstream from there used to be Brown Bridge Dam, built in 1921 and placed into service in 1922, which has been removed.
“The project began in 2005, when the owners of the dams wanted to assess all of them for their environmental, social and economic pros and cons,” explained DNR Lake Michigan Basin coordinator Todd Kalish. “In 2009, the owners of the dams -- Grand Traverse County, which owns Sabin and Boardman dams, and the city of Traverse City, which owns Union and Brown Bridge dams – decided to remove the dams for a variety of reasons.”
Economics was a major factor. The dams were all in need of repair for safety reasons, and using the dams to generate hydropower was not economically feasible, Kalish said.
Removal of the Brown Bridge Dam will allow brown trout, like this one held by DNR fisheries biologist Mark Tonello, access to more than 100 miles of additional river and stream. |
projected cost of repair and maintenance would have been $16 million -- twice as much.”
The benefits of removal are well-documented, Kalish said. Not only would the removal allow fish passage up and down the system, but it would enhance the cold-water fish community in what had been a cold-water system.
“Not just trout, but aquatic insects, sculpins, those sorts of things,” Kalish said.
There are additional benefits, too, Kalish said. The area that was previously under impounded water would provide wetland and upland habitat. And the impounded water supported warm-water fish – bass, pike, etc., -- that predate trout. Dams prevent the natural movement of sediment and woody debris downstream and discharge unnaturally warm water into the river. And the zebra mussels that became established in the impounded water wouldn’t have been there without the dams.
“The Brown Bridge Dam is completely gone,” Kalish said. “The cost of removal was about $4.4 million.
“The 200-acre Brown Bridge impoundment now has a more diverse environment – high-quality river, fast-moving water, gravel and lots of insects. The benefits of the dam removal greatly exceed just fish.”
The dam removal has resulted in restoring a mile and a half of trout stream and reconnected the stream to another 145 miles of streams. The project team is working to put in woody structure in the restored channel above the old Brown Bridge site and is monitoring the vegetation in the flood plain to make sure invasive species do not become established.
The project is now in a period of study, Kalish said. Ultimately Boardman and Sabin dams will be removed and Union Street Dam will be modified.
Kayakers paddle on the newly restored Boardman River above the old Brown Bridge Dam site. |
out of the watershed, but we want the capacity to pass species that are beneficial. Currently, it has a fish-passage structure, but it only allows fish with strong jumping ability – such as Chinook salmon and steelhead – to pass. But we’d like to have the capacity to pass other species as well – brown trout, walleye, sturgeon, Great Lakes muskie – as well as to limit other species. Right now we don’t have that capacity.”
The removal of Boardman Dam includes a bridge that crosses the river at the dam site. Currently, the river crossing is one lane, which restricts traffic on it.
“We’re working with the road commission and the county to enhance that crossing,” Kalish said.
The cost of removing the remaining two dams is estimated at around $12.9 million. Funding will come from a variety of sources: the DNR’s dam management grant program, the Great lakes Restoration Initiative, the Great Lakes Fishery Trust, the National Fish and Wildlife Foundation, the U.S. Fish and Wildlife Service, the Frey Foundation and other sources.
“We don’t anticipate any major construction or de-construction to occur this year, but we expect both next year," Kalish said. "The current plan is to address Boardman Dam – which is classified as a high hazard-potential dam by the Michigan Department of Environmental Quality – first, then Sabin Dam and do the Union Street Dam construction in conjunction with one or the other.
“We hope to finalize the plan specifications for bridge construction and Boardman Dam removal this year.”
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