Water Management Report for Cumberland River Basin

Barkley

Lake Barkley is formed by Barkley Dam at CRM 30.6. It is the most downstream dam on the Cumberland River. Lake Barkley extends to the foot of Cheatham Dam at CRM 148.7. As of mid-August water quality conditions in the main stem portion of Lake Barkley were in reasonably good condition considering the ongoing extreme summer heat wave. The principal issue is the extremely warm water produced by mixing of cooling water from Cumberland City Fossil Plant (~CRM 103) with the Cumberland River. The TVA generating facility uses most of the river's flow for cooling, and produces a zone of very warm (900F+) water that extends many miles downstream. Much of the focus of the Corps water management effort on the Cumberland River system has been focused at keeping this very large generating plant in operation. This has become even more critical in light of the recent 1000+ weather.

The Tennessee Valley Authority's Cumberland Fossil Plant is a critical facility that Corps water management actions are intended to benefit.

Three water quality monitoring trips have been undertaken on Lake Barkley this year so far, with a total of five planned. So far only minor problems have been noted with water quality with the exception of the warm water. One fish kill was documented involving mostly striped bass on Lake Barkley below the mouth of Little River during the week of August 13. The exact cause of this particular fish kill are unknown, but could be related to a localized heavy, rainfall event suddenly forcing poor quality water out of a major embayment into the main channel of the Cumberland River/Lake Barkley. In general, dissolved oxygen levels have been observed to be acceptable in the main channel portions of the lake despite the reduced flows and warm temperatures.

Outflows from Barkley Dam continue to be a single unit discharge to maintain navigation and water quality of the approximate 30 mile long tailwater before its confluence with the Ohio River. So far, the single unit discharge has not resulted in any known issues for commercial navigation using the Cumberland River below Barkley. In addition Lock and Dam 52 (operated by the Louisville District Corps of Engineers) on the Ohio River has raised water levels in the Cumberland by setting in place additional portions of the dam structure.