Tom Sauk Reservoir owned by Ameren UE was operational in 1963 and was the largest pumped storage plant in North America. The $50 million dollar engineering feat is built atop 1,900 foot Proffit Mountain. When electric demands are low (nightime) water is pumped from the lower reservoir to the upper reservoir. At peak enregy time water is t ...
Updated: Apr 05, 2007 7:03pm PST