5 years or so ago, we hosted two rogaines, including the North American champs, on Johnson Shut Ins SP, Taum Sauk Mountain SP (at 1772 feet - highest point in MO! - control and Snicker bars there for the rogaine), and Ameren UE lands. An easy control was next to a 50-acre, 90 foot deep Ameren UE reservoir on the top of Proffitt Mountain. This morning, it was registered as refilled at 5:12 am, but it kept pumping up more water from the lower reservoir. At 5:24 am, it registered near empty, over 1 billion gallons of water had breached the berm, flowing northwest into a huge re-entrant, then hit the Black River, rode south through Johnson's Shut-Ins SP, but fortunately the Lower Reservoir dam (downstream a couple miles) held. The Upper Reservoir's purpose is to pump water up when electricity is cheap (usually nights) and down when it is more costly (especially summer days).
This aerial photo from Terraserver shows the area well - the kidney shaped 'lake' was the reservoir.
http://terraserver.homeadvisor.msn.com/image.aspx?...
The park superintendent's house near the SP campground was splintered; his family swept over a hunderd yards downstream; amazingly the parents and three young children survived, ending up in two groups in muddy fields - the children are hospitalized - hopefully 'just' hypothermia. Only other damage seems to be roadways and a car and couple trucks swept off of highway N - no further injuries reported yet.
Lesterville is about 5 miles downstream, but unaffected since the dam held.