Taum Sauk Hydroelectric Power Station - Size and Location

Size and Location

The original upper reservoir had a capacity of 4,350 acre feet (5,370,000 m3). The upper reservoir is 800 feet (240 m) above the hydroelectric plant, which gives it a greater head than that of Hoover Dam. The two are connected by a 7,000 feet (2,100 m) tunnel through the mountain.

This powerplant is a net consumer of electricity; the laws of thermodynamics dictate that more power is consumed pumping the water up the mountain than is generated when it comes down. However, the plant is still economical to operate because the reservoir is filled at night when the electrical generation system is running at low-cost baseline capacity. As a way to store excess power until it is needed, it has been described by the utility as "the biggest battery that we have."

The Taum Sauk reservoir is atop Proffit Mountain, not Taum Sauk Mountain, which was often a source of confusion to visitors to the site when it was open to the public prior to the reservoir failure. Taum Sauk Mountain, the highest point in Missouri, is about five miles (8 km) east of Proffit Mountain and is home to a state park. The reservoir is plainly visible from the lookout tower on Taum Sauk Mountain. The upper reservoir is also visible from Route 21 north of Centerville.

Before the failure of the upper Reservoir visitors could usually drive to the top of Proffit Mountain and walk a ramp to an observation deck at the top of the reservoir. At the entrance gate Ameren also operated a museum highlighting the natural history of Missouri. The powerplant was frequently visited by geology students because of a striking example of Precambrian/Cambrian unconformity in the rock layers exposed by the plant's construction.