Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV
Significance: Each plant epitomized the predominant low head hydroelectric technology in use at the time of its construction, Dam 4 uses tandem, multiple-runner, horizontal shaft turbines connected by rope drives to horizontal shaft generators. This plant is probably the last commercially operated rope-driven hydroelectric plant in the United States.
Unprocessed Field note material exists for this structure: FN-16
Survey number: HAER WV-27