WisDOT planning to take out dam in Rock Falls and replace Hwy. 85 bridge

By LeAnn R. Ralph

TOWN OF ROCK CREEK  — Rock Creek has been dammed up for nearly 150 years, and the Wisconsin Department of Transportation is now planning to remove the dam in Rock Falls and to replace the state Highway 85 bridge.

WisDOT and the state Department of Natural Resources held a public informational open house about the project at the Rock Creek Town Hall April 24.

The dam was originally constructed in 1878 out of wood and was upgraded in 1923 to concrete. The dam has not generated power for years, said Tyler Rongstad, a civil engineer with WisDOT. 

The bridge was built in 1941, received a new deck in 1987, and “it is due for replacement,” he said. 

The project could be completed as early as 2020, although construction is likely to take place sometime between 2020 and 2024, depending on when funding is available, Rongstad said. 

Highway 85 will be detoured from April to November during the time the dam is being taken out and the bridge is being rebuilt, he said. 

The detour will be routed on Highway 10 and Highway 37, and while it is a long detour, it is better than trying to do half of the bridge at a time, which would take a couple of years, Rongstad said. 

The detour is about 30 miles and is intended mainly for truck traffic, he said. 

If half the bridge is done at a time, temporary signals must be put up, and people would likely end up waiting as long as it would take them to drive the detour. Constructing half of the bridge at a time also is more expensive, Rongstad said. 

The project will include a walking path down to the creek and will give the park more space. Most of the dam and the mill foundation will be removed. The project does not include a full upgrade of the park, “but it will look better than it does now,” he said, noting that access to the creek will be safer since the drop is about 50 feet now. 

Dunn County currently owns the park.

After the dam is taken out, the plan is to allow Rock Creek to find its natural course. 

“The dam is hardly functioning as a dam right now. The water is working its way around (the structure). It is holding back a little water, but after we take it out, the creek will be able to get back to natural conditions,” Rongstad said. 

The estimated cost of the project is $2.3 million, he said.

Rock Creek is a tributary of the Chippewa River.