Downstream Fish Passage at Hanover Pond Dam Through the Use of an Archimedes Screw Generator

Abstract Background: In 2016, an Archimedes Screw Generator (ASG) was installed at the Hanover Pond Dam located in Meriden, CT on the Quinnipiac River to support hydroelectric operations for New England Hydropower Company, LLC (NEHC). The ASG is the first of its kind implemented in the United States, and while they are largely described as ‘fish-friendly’, adequate scientific literature evaluating fish passage is lacking at these facilities. The Connecticut Department of Energy and Environmental Protection (CT DEEP) with consultation from U.S. Fish and Wildlife Service (USFWS) and Kleinschmidt Associates designed and implemented a study to evaluate American Shad downstream fish passage at Hanover Pond Dam. The objective of this study was to document whether American Shad would enter the darkened penstock, pass beneath the downward closing sluice gate, and utilize the ASG for safe downstream passage. A radio telemetry study was designed with three fixed monitoring stations; including one station upstream of the dam, another station within the intake structure, and a third station downstream of the dam. Twenty adult American Shad were collected from Holyoke Dam Fish lift, transported to Hanover Pond, and radio-tagged. Fish were released upstream of the dam and monitored from May 30 to July 15, 2019.Results: In total, 16 fish were detected upstream of the dam, and 8 of those fish passed downstream. Seven of the eight fish that passed through the project (87.5%) utilized the intake of the ASG before being detected at the downstream receiver. One fish passed downstream via the spillway and/or use of a notch in the dam. All fish that passed downstream were detected with subsequent 2-second tag bursts at the downstream monitoring station, suggesting a 100% survival rate through the ASG.Conclusions: These results support the suggestion that the Archimedes Screw Generator is a ‘fish friendly’ operation.