AmerenUE officially unveiled its new $490 million, 1.5 billion gallon Taum Sauk reservoir in Lesterville, Missouri on May 27, 2010. On December 14, 2005, Ameren Energy's retention reservoir developed a breech, dumping billions of gallons of water and washing away homes and cars. Water in the fifty-acre upper reservoir of the hydroelectric plant, emptied in 12 minutes raising the level of the Black River in Southeastern Missouri, about 120 miles from St. Louis. The treeless area on the lower left is where the water gushed out of the reservoir. UPI/Ameren UE