It was one of four related projects on the Clackamas River: the Oak Grove Hydroelectric Project (developed 1923–56), the North Fork dam (1958), and the Faraday Dam (1907–10), all upstream (south) of River Mill.

[4] All but Faraday, demolished 2018, are still owned and operated by the successor company, Portland General Electric.

[5] The principal designer of the original Mill Run Dam was the Norwegian immigrant Nils F. Ambursen (1876–1958).

Based in Boston, his Ambursen Hydraulic Construction Company designed over a hundred dams in the United States from 1903 through 1917.

River Mill is one of only three Ambursen-type dams built west of the Mississippi, and evidently the only one to survive.