[2] The hydroelectric plant began producing electricity in 1919 with 3 turbine/generator units, for a total of 19 MW.

Completion of the dam impounded the Housatonic River and created what came to be Lake Zoar, a lake with 27 miles of shoreline, and covering an area named "Pleasantvale" or "Pleasant Vale", which had been part of Oxford and Stevenson.

[2] The Stevenson plant was developed by the Rocky River Power Company, founded in 1905 by J. Henry Roraback to produce hydroelectric power on a tributary of the Housatonic, with operating rights expanding to the entire Housatonic watershed in 1909.

The project was designed by Birkinbine Engineering Office, Charles T. Main Associates of Boston, Massachusetts, and J.A.P Crisfield Co., and was built by C. W. Blakeslee Co., a local contractor.

[4] An urban legend exists that asserts a worker fell into the cement as it was being poured and was never heard from again.