Don Getty, manager of the dam rehabilitation project, said unanimous agreement came out of review meetings last week that the $594 million project to stop uncontrolled seepage in the dam is a quality job.
“Reviews were great! Better than I expected,” said Getty. Recommend-ations that the mile-long dam is safe were sent in two reports to the U.S. Army Corps of Engineers’ Great Lakes and Ohio River Division in Cincinnati.
Getty said two things were discussed during the meetings: (1) Quality of the barrier wall to ensure it was built to specifications, and (2) performance of the dam based on information from 350 monitoring instruments inside the dam. There are additional steps in the review process, he noted.
The reports are currently under review and Brigadier General Margaret W. Burcham, commander of the Great Lakes and Ohio River Division, is expected to give the green light for Lake Cumberland to rise 20 feet by this summer.
“April 1 is the target date for the lake to start rising,” said Getty. “It could happen a few days before or a few days after,” he added.
The 20-foot rise this summer will raise the lake from its current target of 680 feet above sea level to between 700 and 705 feet. Getty said the lake likely will remain just over 700 feet this summer and the green light to raise the level to normal pool stage will be given in December for the 2014 vacation season.
Completion of the barrier wall did not completely finish the rehabili-tation project. Weddle Enterprises, Somerset, is currently narrowing the work platform on the upstream side of the dam from 75 feet wide to a 30-foot-wide platform that will remain. The platform was built to accommodate heavy equipment that fashioned the barrier wall by drilling 50-inch, overlapping holes filled with concrete.
The wall, a minimum of two feet thick, extends from the work platform 275 feet downward to about 100 feet into limestone bedrock beneath the dam.
The project, of a scope never done anywhere in the world, is designed to stop uncontrolled seepage that has plagued the dam since it was completed in December 1950. Wolf Creek Dam in 2005 was declared in high risk of failure and the water level was lowered 40 feet in January 2007 to facilitate the current rehabilitation project that is nearing completion.
The earthen section of the dam is bolstered with two additional walls: A shorter barrier wall extending about 15 feet into the limestone bedrock was installed during the 1970s following a near breech of the dam during the late 1960s, Also, remaining in the dam is a protective concrete embankment wall fashioned with 6 feet-by-9 feet concrete panels to stabilize the earthen embankment while the most recent wall was inserted.