Graham Lake in Hancock County, Maine is a eutrophic reservoir formed by the construction of a hydro-electric power dam in 1922 four miles (6 km) upstream from Ellsworth, Maine. The first dam was a hastily built earthen dam built by the Bangor Hydro Electric Company. It failed in 1923, flooding downtown Ellsworth and doing almost $8 million in property damage. The dam was rebuilt and operated by Bangor Hydro until its sale in 1999. The dam has since been acquired by Pennsylvania Power & Light which continues to use it to generate electricity.