Locks and Dams

Corps Planning Drawdown Of Thatcher Pool On Ouachita

The Vicksburg Engineer District reported November 5 that it is monitoring river levels near Thatcher Lock and Dam, Mile 281.7 on the Ouachita River. In recent weeks, the pool elevation has fallen below normal pool level due to a leak in the seal of the hinge crest gate.

The district plans to draw down the pool to make repairs to the seal, but the pool level must reach 71 feet at Thatcher before engineers can inspect the seal to determine the exact cause of the leak.

“The Corps of Engineers team remains committed to communicating and working with local stakeholders, partners and city officials to provide technical assistance,” said Vicksburg District Commander Col. Robert Hilliard. “Safety remains our priority, and the team will work steadfastly to make the repairs as quickly as possible when river levels are ideal.”In the November 5 notice, however, the Corps also said the pool level would rise over the next week because of expected rainfall and the drawdown of Lake Hamilton by Entergy’s hydropower operations. The river rose from about 74 feet on November 4 to as high as 78.12 feet on November 8. As of noon on November 10, the stage was 77.68 feet.

The drawdown will not occur until the Camden, Ark., water supply is prepared and the Corps has materials in place to inspect and potentially repair the seal. Pending coordination with the city of Camden, the drawdown may occur as soon as the last week of November, the Corps said.

Once the gate seal is exposed, the district will perform inspections on the gate and determine what is necessary for a temporary or permanent fix. If possible, repairs will be made immediately, and the pool will be raised back to normal pool elevations.

The Vicksburg District said it is committed to communicating with partners and stakeholders regarding updates to the progress of Thatcher repairs. The district has been in communication with the Ouachita River Valley Association, the city of Camden and the Union County Water Conservation Board as well as the Arkansas Game and Fish Commission and Arkansas Natural Resource Commission. 

Completed and put in operation in 1984, Thatcher Lock and Dam creates a navigable pool all the way to Camden, a distance of 52 river miles. Thatcher is the northernmost lock and dam on the Ouachita River.