Fishheart Ltd., a company based in Finland, has started a three-year project at the Tunnel Hydropower Plant in Preston, Connecticut. The project is the company’s first large-scale installation in North America and is being conducted in partnership with FirstLight Power, which owns the plant.
The project follows earlier testing in spring 2024 at the Santee Cooper Hydroelectric Project in South Carolina. Both efforts aim to support migratory fish species such as American Shad and river herring, which are part of state and federal restoration programs.
For the first two to three years, the Fishheart system will operate at the Tunnel Hydropower Plant. If it performs successfully, the system may be moved to the Stevenson Hydropower Plant in Monroe, Connecticut, for permanent installation.
The purpose of the project is to test the Fishheart system’s ability to attract and guide fish safely past the hydropower facility. The system includes a floating fishway below the dam and a pipeline over the dam. It uses a siphon mechanism to create upstream attraction water that encourages fish to enter. According to Fishheart Ltd., this design reduces the need for permanent infrastructure and is more cost-effective and flexible than traditional fishways.
Fishheart systems have been in use at four river sites in Finland for several years. The company is also running a separate test project in Menindee, Australia.
The Connecticut project is being observed by agencies including NOAA’s National Marine Fisheries Service, the US Fish and Wildlife Service, and the Connecticut Department of Energy and Environmental Protection. Approval from these agencies is necessary for the system’s future use in North America.
“For FirstLight, the long-term goal of the trial is to develop a successful, cost-effective solution for fish passage where it is required at its hydropower plants in North America,” the company said. It chose the Tunnel Hydropower Plant for initial testing because it is located on a small river with the presence of the target fish species, allowing for controlled testing conditions.
The Fishheart system is designed to operate for 2–3 months each year during the fish migration season, typically from April to July.
