How can raising the level of Lake Cumberland hurt a fish?
The question has been floating around the newsroom since the U.S. Army Corps of Engineers announced Wednesday that Lake Cumberland will not return to normal operation this summer. The reason: Duskytail darters, an endangered species, have been found in five miles of stream habitat in headwaters of the lake.
Lee Andrews, field supervisor for U.S. Fish and Wildlife Service’s Kentucky Field Office and the person most in the know about the duskytail darter dilemma, explains:
The duskytail darter, sometimes called tuxedo darter, is protected by the federal Endangered Species Act. The little fish lives, among other places, in the Big South Fork of the Cumberland River. The Big South Fork flows out of Scott County, Tennessee and north through McCreary County before emptying into Lake Cumberland near Burnside.
The 2 1/2-inch darter, a member of the perch family, can only survive in flowing water, preferably over the boulder-strewn bed of the Big South Fork. Impoundment of Lake Cumbe-rland in 1951 backed up the Big South Fork River, extending the lake into where once was a river. Lack of flowing water and sediment covering rocks in stillness of the inundated river ruined habitat for duskytail darters.
Drawdown of the lake in 2007 to facilitate repairs at Wolf Creek Dam allowed flowing water in the Big South Fork to wash away sediment and recreate a habitat for duskytail darters along a five-mile stretch of the river that previously had been backed up by the lake for 56 years.
A Tennessee Valley Authority (TVA) survey discovered the rare darters in the stretch of the river that will be inundated again when the lake returns to normal, Andrews said. No exact population of the fish was determined by the TVA survey, but counts ranged from 1 to 20 fish in spots surveyed, he said.
Andrews doesn’t expect it will take a long, drawn-out period to come up with an answer to save the endangered darter from a higher lake. He said U.S. Fish and Wildlife Service has a maximum of 135 days to resolve the problem from the time it receives a biological assessment from the Corps.
“We expect to receive the assessment as early as next week,” he noted. “That means at the maximum we will be done by June.” However, he added: “We expect to have it done well in advance of that.”
Simply put, wildlife authorities may remove the endangered darters from the five-mile stretch of the Big South Fork and put the fish somewhere else in an appropriate habitat.
Lake Cumberland, before it returns to normal operation, must overcome the hurdle of the endangered darter and get a final OK from Brigadier General Margaret W. Burcham, commander of the Great Lakes and Ohio River Division of the Corps. Burcham’s approval relates to safety of Wolf Creek Dam.
Don B. Getty, manager of the $594 million Wolf Creek Dam Rehabili-tation Project, said the Corps already has permission to raise the lake to 705 feet above sea level, the same as last summer. He expects the lake to rise to this level in about a month.