Ayers Island Hydro

The Ayers Island Hydro Station was constructed between 1923 and 1924 by the Utilities Power Company. PSNH purchased the facility in 1928 and redeveloped it in 1931, raising the dam 30 feet higher than its original construction.

Ayers Island is the company's northern-most hydro station in the Merrimack Basin and, at 80 feet, it is also the highest dam on the river. In 1988 a downstream fish passage sluice and trap were installed to allow native fish to move downstream from the dam.

Facts at a Glance:

• Turbine/generators: 3
• Turbine horsepower (each): 4,400
• Generating capacity: 8.4 MW
• Max. gross head: 82 feet
• Dam height: 80 feet