Davis Island Dam & Lock No. 1, Ohio River, mile 4.7 on right bank, Pittsburgh, Allegheny County, PA

Includes index to related materials in National Archives RG 77.
Significance: As the first lock and dam on the Ohio River, the Davis Island Lock and Dam was an experimental project testing the skills of the 19th century engineers. Project design achievements included the first rolling lock gates, the largest movable dam built in the 19th century, and the widest chamber of world history. Project construction engineering gained increased efficiency through conversion from manpower to steampower. Especially notable was the study of national and international engineering technology performed during planning and construction phases. The civil engineers associated with the project included several of the founders of the Engineers' Society of Western Pennsylvania; military engineers supervising the project included Frederick A. Mahan, international waterways engineering expert; William E. Merrill, the "Father of the Ohio River Project"; George W. Goethals of Panama Canal fame; and William M. Black and Lansing H. Beach, who later served as Chief of Engineers, US Army. ...
Survey number: HAER PA-65
Building/structure dates: 1878-1885 Initial Construction