Hersey Dam Removal
Village of Hersey
Hersey removes dangerous dam with 100% grant funding.
The Village of Hersey wanted to repair or remove the Hersey Dam, which was in poor structural condition and had been cited as unsafe in two MDEQ Dam Safety Reports. The dam also blocked fish passage and significantly raised the water temperature in the Hersey River, a designated trout stream.
P&N performed a feasibility study for removing the dam with a “controlled drawdown” demolition process to minimize sediment movement, and estimated the costs at only $285,000. Because of its experience with the MDEQ/MDNR permitting process, the P&N team was able to develop a dam removal concept that was both cost-effective and appealing to grant funders.
Hersey worked with the Muskegon River Watershed Assembly to raise 100% grant funding for the project, and MRWA retained Prein&Newhof to oversee the dam removal. The entire project took only six months from “go” to completion, including permitting and design. A favorable bidding climate helped bring the total project in for about 20% less than Prein&Newhof originally estimated.
Before the removal project began, contaminated sediment in an area just upstream and downstream of the dam was removed at the responsible party’s expense. In addition, P&N secured approval from the MDEQ to dispose of all demolition rubble in two existing low spots on the site, provided they were covered with sand and topsoil, and then seeded.
To eliminate the need for sediment dredging and excavation, the P&N team specified a controlled drawdown approach, a regulated process in which the dam is dismantled slowly, gradually directing water through the breach into a prepared training channel. This method prevents significant erosion and sedimentation.
Prein&Newhof worked with the MDEQ to allow the loss of 11 acres of wetlands that were created over 100 years ago when the dam was built – without costly mitigation. In addition, the P&N team was able to eliminate the need for bringing rip-rap bank protection from off-site by sequencing construction to allow for the use of on-site materials.
The upstream shoreline areas exposed by the dam removal were planted with native seeds, trees, and bushes. The Village of Hersey plans to transform the former dam site into a small park with a bike path connecting it to nearby Blodgett Landing Park.
Call Jim Hegarty, P.E. at 616-364-8491 Email at: email@example.com