Coonamessett River Fish Passage & Habitat Improvements, Massachusetts
The Coonamessett River is a small, spring-fed stream that flows into Vineyard Sound. The project site is situated at the downstream end of the river and experiences some tidal influence. Following a long history of mill construction and cranberry cultivation, fish populations and aquatic habitat were in decline. Inter-Fluve was retained by the Town of Falmouth to identify feasible alternatives for improving fish passage at four partial fish barriers, improving fish habitat, and maintaining organic cranberry cultivation and recreational opportunities. Construction, completed in 2018, included hydraulic modeling, sediment sampling, preliminary and final designs, permitting, and construction observation for the removal of two dams, replacement of an understized culvert with a free span bridge, and the channel reconstruction and wetland restoration of three cranberry bogs totaling approximately 30 acres.
Microtopography, seen here, breaks up the surface and brings the wetland seedbank along with peat and other organic matter to the surface. The technique generates a range of micro-environments that allow a diversity of plant species to become established as well as wetland pools in which amphibians reproduce. Photo credit: Adam Soule