Correction: The fish ladder allowing passage was installed when the South Berwick dam was reconfigured in the early 2000s, not in 2017 as previously stated.
With spring’s arrival, the Salmon Falls River has warmed up enough for alewives and blue-back herring to swim upriver again to spawn – and this year for the first time they’ll get a ride around two dams.
On May 11, fish trying to move upriver found themselves trapped in a large steel box near the Counting House Museum, where they were lifted up, poured into a tank and trucked from South Berwick to Somersworth, bypassing both the Liberty Street and Rollinsford’s Project dams.
Andrew O’Malley, fish biologist, backed the trailer with the empty tank to the lift just after completing the first ever transport of fish from the new system at Liberty Street, where he, regulatory specialist Kirk Smith and environmental scientist Jacob Green would wait several hours for the trap to fill again before taking the next batch of fish to Somersworth.
“This was the first run and we moved 55 fish,” O’Malley said.
The three men work for Gomez and Sullivan Engineers of Henniker, N.H., a company specializing in dam engineering, fish passage and stream restoration. A crew from that company installed the “trap and transport” facility last year.
The water needs to warm up a little more before fish will swim in greater numbers, according to O’Malley. The target goal is 20,000 fish for the first year.
Temperatures of 50 or 55 degrees will bring more fish upriver, with the season running from mid-April through June depending on water temperatures and location, according to the Maine Department of Marine Resources website.
During peak migration, crews may operate during all daylight hours, according to Kristin Kelly of Green Mountain Power of Vermont, the company that runs both the South Berwick and Rollinsford dams. The trap is closed and the fish ladder reopened whenever the crew is not available to tend the fish passage.
The counter recorded 177,374 fish in 2024, up from 4,405 in 2017, when active monitoring increased significantly, according to New Hampshire Fish & Game Department reports. A fish ladder, for up and downstream passage, was originally installed when the South Berwick dam was reconfigured in the late 1990’s, according to the Low Impact Hydropower Institute.
The new fish trap and transport facility were required by the Federal Energy Regulatory Commission for better fish passage around the dams before the commission would renew the Rollinsford Project’s hydroelectric license.
