Overview of the Taum Sauk Pumped Storage Power Plant Upper Reservoir Failure, Reynolds County, MO

In 1953 Union Electric began considering construction of a pumped storage facility to generate electrical power during peak usage periods, which was a relatively new concept at that time. The pumped storage scheme had the advantage of being able to operate at full power almost immediately, allowing the owner to postpone construction of a much larger steam plant by harnessing some of the company’s off peak power. Construction of the lower and upper storage reservoirs was authorized for the Taum Sauk site in December 1959 (Gamble, 1960), and operations began in 1963. Although other sites were considered, the St. Francois Mountains of southeast Missouri was selected. The rugged topographic relief provided the required head for the efficient operation of a pumped storage power plant and favorable geology was conducive to the construction of the needed reservoirs. The final selection of a location for the facility, named the Taum Sauk Pumped Storage Hydroelectric Power Plant, was chosen along the East Fork of the Black River and atop Proffit Mountain near Annapolis, MO in Reynolds County about 5 miles from Taum Sauk Mountain, the highest point in the state. Proffit Mountain is the 6th highest point in Missouri and provides around 800 feet of elevation differential between its peak and the valley of the East Fork of the Black River below. 21 pp., 18 references.