In 2019, we celebrated two habitat restoration milestones on Maine’s Sheepscot River, where fish passage barriers were removed at the two lowermost dams on the river. The Coopers Mills dam in Whitefield was fully removed in 2018. The Head Tide dam in Alna was partially removed and fish passage rebuilt in 2019. The dams were removed in partnership with the Atlantic Salmon Federation and the two towns where the dams were located.
For decades, fish returning to the Sheepscot River to spawn have been delayed at the bottom of these dams. They’re often unable to get by to reach their historic spawning grounds upriver. Opening up river habitat can help increase the populations of these fish, many of which are prey for popular recreational fish like tuna and striped bass.
The Sheepscot River is the southernmost river in the United States where endangered Atlantic salmon, a NOAA Species in the Spotlight, consistently spawn in the wild. The river also supports a longstanding commercial alewife fishery, where lobster fishermen regularly line up in the spring to purchase bait. It also provides spawning grounds for American shad.
Coopers Mills Dam Comes Down
In May 2019, dozens gathered on the banks of the Sheepscot River to celebrate the removal of the Coopers Mills dam. It was a milestone nearly two decades in the making.
The dam removal project included an innovative dry hydrant system that provides water for fire fighting and a small park with scenic overlook. Stone from the former dam was repurposed to create the overlook and pathways around historic mill foundations, locally known as the Zen Garden.
Celebrating the Head Tide Dam Removal
On October 31, 2019, in the pouring rain, the restoration community in Maine donned raincoats and carried umbrellas, and gathered to celebrate the breach of the Head Tide dam on the Sheepscot River, home to endangered Atlantic salmon.
The historic mill site was gifted to the town of Alna with a stipulation that the dam not be removed. This project required some creative and collaborative work-arounds.
The NOAA Restoration Center oversaw the design, permitting, and construction of the fish passage improvements. The team used computer modeling to make sure that the speed of the water through the opening did not exceed the swimming capabilities of sea run fish. They also made it look and feel as natural as possible, adding roughness to the rocky elements.
Salmon Swimming Freely
In the fall, biologists from the Maine Department of Marine Resources confirmed that adult salmon were freely swimming upstream of both the Head Tide and Coopers Mills dams!
In 2020, NOAA, the Atlantic Salmon Federation and other partners are looking at the feasibility of other fish passage projects in the Sheepscot River watershed. We’re especially looking at historic alewife ponds to restore this important sea-run species to its native range.
Thank You to Our Partners
- Atlantic Salmon Federation
- Town of Alna, Maine
- U.S. Fish & Wildlife Service
- Maine Department of Marine Resources
- The Nature Conservancy
- Midcoast Conservancy
- Inter-fluve (design engineer)
- SumCo Eco-Contracting, LLC (construction contractor)
Contact Matt Bernier, NOAA Restoration Center, Orono, Maine, (207) 866-7409