At a Glance
The removal of an obsolete dam improves diadromous fish migration and habitat in a tributary to the Lower Hudson River.
Recognizing that the most effective way to restore fish migration is to remove a dam that has outlived its usefulness, the Hudson Valley Stream Conservancy (HVSC) sought to remove the obsolete five-foot-high Sprout Brook Dam. Located within a popular park, it is the first in a series of small dams along the Sprout Brook, a lower Hudson River tributary. In partnership with Westchester County and with funding from NY DEC, HVSC turned to Biohabitats for help in removing the dam and restoring Sprout Brook to improve diadromous fish migration and habitat, most notably for the restoration of historic alewife (Alosa pseudoharengus) and American eel (Anguilla rostrata) runs.
After meeting with representatives from the dam’s owner, the Town of Cortland, Biohabitats conducted a detailed site investigation. This included geomorphic observations of the upstream and downstream channels, dam/weir measurements, identification of surface utilities and infrastructure that could be impacted by the project, impounded sediment probing, collection of sediment samples for testing, and the identification of any rare, threatened, or endangered species and potential historic and archeological concerns. Biohabitats then estimated the quantity of impounded sediment, conducted a hydrologic assessment and hydraulic modeling, and developed a plan to manage the impounded sediment–all of which has the potential for mobility post dam removal.
Biohabitats is currently preparing engineering design plans, permit applications, and an engineering design memorandum which includes a sediment management plan. The design emphasizes minimizing impacts to the river system and the surrounding park. When completed, the project will not only improve fish migration and habitat; it will also enhance water quality, biodiversity, and recreational opportunities.
Ecological Restoration, Infrastructure
Hudson Valley Stream Conservancy
Cortland, NY, New York, United States
- Franklin Survey
- Alpha Laboratories