Louisville, KY -- The U.S. Army Corps of Engineers Louisville District Dam Safety Office is continuing dam investigations at two Corps sites in Indiana. The field work, which begins next week, will occur at Brookville Lake Dam, located near Brookville, Ind., and J.E. Roush Lake Dam, near Huntington.

The Corps has ongoing investigations underway since 2005 for Roush Dam and since 2008 for Brookville Dam. Prudent management of these dams requires additional instrumentation at key locations to provide subsurface data and enhance the ability to monitor dam performance. The planned work includes drilling to install small diameter wells that will be used to monitor the water levels within the dams and in the foundations beneath the dams.  Instruments used to detect potential ground settlement and slope movement will be installed at J.E. Roush Dam.

Brookville Dam was constructed on a large valley containing sand and gravel soils. These soils allow some flow of water from the lake under the dam. In order to control the water flowing under the dam, relief wells are used to collect this water and provide a safe and controlled exit point. The instruments being installed at Brookville Dam will be used by engineers to monitor the efficiency of the relief well system.

Past settlement of the dam embankment has been observed at J.E. Roush Dam. The additional instruments will assist to determine the extent of the settlement zone and detect if additional settlement is occurring. All earthen embankment dams settle. This settlement usually decreases gradually over time and then stops. The amount of settlement that has occurred at the J.E. Roush Dam is within the range expected for a dam of this size, and the instruments that the Corps plans to install will aid in determining if the embankment is continuing to settle, or if the settlement has ceased. The new instrumentation will assist with these efforts.

The Corps’ contractor, Arcadis – Thelen Joint Venture, will begin drilling at Brookville Dam and J.E. Roush Dam next week on or around Sept. 13. The work will take approximately eight weeks. Visitors to the lakes will observe truck and track mounted drilling equipment on the dam slopes and near the tailwater areas during this time.
 
The Corps Dam Safety program seeks to minimize risk at its projects. Louisville District dams are staffed with project personnel seven days a week and inspected routinely by District engineers. Engineers annually inspect all regional reservoir dams. A more intensive team inspection occurs every five years.