The Kenyon Mill Dam, located on the Pawcatuck River in Kenyon, RI, was historically constructed to support mill operations at the adjacent textile mill. In conjunction with two other fish passage projects immediately downstream, the Wood-Pawcatuck Watershed Association, in cooperation with NOAA and RIDEM, secured funding to modify the structure to provide fish passage at the site for Blueback Herring, Atlantic Salmon, American Shad, and American Eel.

The mill site relied on the dam’s impoundment as a water source for its fire suppression system. Fuss & O’Neill worked closely with the mill owner to evaluate alternatives allowing removal of the dam by providing replacement water storage facilities. Following an assessment of upstream impacts (to bridges and natural resources in the state’s largest freshwater wetland system resulting from dam removal), an approach was selected to construct a nature-like rock ramp fishway that maintains the impoundment.

We performed hydrologic/hydraulic analyses of flood flows and prepared FEMA floodplain map revision submittals; conducted field investigation of impounded sediments; and developed design to minimize mobility and impacts to upstream bridge.  We also developed construction phasing to ensure that headpond elevations were maintained for the mill’s fire suppression system.