Seneca Dam was the last in a series of dams proposed on the Potomac River in the area of the Great Falls of the Potomac. Apart from small-scale dams intended to divert water for municipal use in the District of Columbia and into the Chesapeake and Ohio Canal, no version of any scheme was ever built. In most cases the proposed reservoir would have extended upriver to Harpers Ferry, West Virginia. The project was part of a program of as many as sixteen major dams in the Potomac watershed, most of which were never built.