This report presents a preliminary evaluation of the addition of hydropower at the existing navigation Lock and Dam 7. The study shows that installation of a hydro plant with a 4,800-kW (kilowatt) or 7,200-kW nameplate rating is economical. Pertinent data concerning the site and two optional installations are given. Severe environmental impacts do not appear to be associated with construction of a plant of the sizes investigated despite the proximity of the lock and dam to an environmentally sensitive area. The District Engineer recommends that the Corps of Engineers prepare a feasibility report which can serve as a basis for congressional authorization for hydropower plant construction at Lock and Dam 7.