Wolf Creek Dam work to be showcased Friday

Posted April 17, 2013 at 2:03 pm

GrindingWheels.psd

Above, one piece of equipment used during the Wolf Creek Dam rehab project included these large grinding bits that drilled the 50 inch wide by nine feet long hole through the dam’s surface and into the bedrock, reaching a depth of 275 feet. Those overlapping holes, or piles, were filled then with concrete.

Last dam pour . . .

The seven-year, nearly $600 million project that has stopped serious seepage through and underneath the nearly mile long structure that forms Lake Cumberland has been completed successfully, and the government agency in charge of the endeavor now wants to celebrate.

What’s more – you’re invited to the event that will mark the milestone.

The U.S. Army Corps of Engineers will be hosting the general public this Friday morning at the Wolf Creek Dam barrier wall completion ceremony.

The event gets underway at 10:00 a.m.

According to a press release issued last week, the U.S. Army Corps of Engineers, its contractor Treviicos-Soletanche Joint Venture, and other local, state and national officials are expected at this event. Dignitaries will speak and initiate the ceremonial last concrete placement on the barrier guide wall, which signifies the official completion of the barrier wall installation.

“This is a monumental occasion for both the local and downstream communities that rely on the dam for its economic and water management benefits,” said Lt. Col. James A. DeLapp, Nashville District commander.

Parking for the event is available at Halcomb’s Landing. A shuttle service to the ceremony location on the work platform begins at 8:30 a.m.

There will be a handicapped accessible shuttle. The public can also walk from the parking area, but it is close to a mile distance each way. Attendees are encouraged to arrive early to accommodate being in place in time for the start of the ceremony. Open seating is on a first-come basis. The remainder is standing room.

The event is planned rain or shine. A tent will cover only a portion of the seating area so participants are encouraged to bring umbrellas if inclement weather is anticipated.

Portable rest=rooms will be available, but food and drinks will not. Participants are allowed to bring a snack and water if needed.

The Halcomb’s Landing boat ramp will be closed beginning at 10 p.m. April 18 and will reopen at 1 p.m. April 19 to accommodate parking for the ceremony.

The problems with Wolf Creek Dam that brought about the extensive rehabilitation project stemmed from the way it was originally constructed back in the 1940s and 1950s.

Built atop a system of karst geology that included caves and caverns below its foundation, water began seeping underneath the structure, weakening the integrity of the dam that is a combination of concrete structure joined with a earthen section that makes up the nearly mile-long feature that holds back the Cumberland River to form Lake Cumberland.

The project to repair the leaks underneath Wolf Creek Dam, has involved constructing a barrier wall by drilling a series of large holes that reach depths of as much as 275 feet below the dam’s work platform, into solid bedrock.

Those overlapping drilled holes, referred to as caissons, were then filled with concrete in a “leap-frog” fashion to form a deep cutoff wall that will hopefully prove to be the final fix to stop the water from seeping through and beneath the dam.

Back in the 1970s, a similar problem was discovered and a project similar to the one now nearing completion was made in an effort to stop the leaks and seepage then.

However, it was later determined that the earlier repairs were neither deep enough nor long enough to have been totally successful.

The current repair project was not only considerably deeper in its placement of concrete below the dam’s foundation, but unlike the repair attempts in the 1970s, this time included the entire length of the earthen portion of the dam.

The most recent project also saw crews paying particular attention to the repair efforts where the concrete portion of the structure and the earthen portion joined.

That area was referred to by both the Corps of Engineers, as well as by the construction firm completing the project, as “Critical Area No. 1” and was the area where the most problems were encountered during the project.

The U.S. Army Corps of Engineers Nashville District placed concrete for the last pile of the barrier wall March 6, which completed the last and most critical component of the dam safety project required to mitigate seepage through the karst geology deep in the foundation of Wolf Creek Dam’s embankment.

It was the last of 1,197 piles that are approximately four feet in diameter and extend as deep as 275 feet, traversing through the embankment, and well into bedrock. Altogether they interlock to form the barrier wall.

The Lake Cumberland pool is being raised from elevation 680 feet above sea level, which was maintained during construction, to the first incremental operating zone between elevations 700 and 705. The lake level is currently at 695 feet.