Shoring Up Dams Must Be First Priority For Corps

February 6, 2006, The recent decision to reduce water levels on Lake Cumberland while Wolf Creek Dam is repaired has left residents with many unanswered questions. They want to know the severity of the risk, the impact the repairs will have on them and what they should do if the dam were to fail. These questions need answers, and the U.S. Army Corps of Engineers tells me they are working to inform residents.

The Corps is holding a series of public meetings to let residents know about the rehabilitation plan. Meetings have been planned for Davidson and Sumner counties, and I hope the Corps will hold additional meetings in other counties downstream of Lake Cumberland. The Corps has also decided to release maps that show potential flooding in the event of a dam break. While these maps should have been released sooner, they will be a valuable resource as residents try to determine their level of risk.

There is no question that addressing the seepage problem at the dam will greatly enhance safety for the Middle Tennesseans who live downstream. Although the rehabilitation may cause some inconveniences now, it is important to remember that public safety is the primary concern.

Lake Cumberland is the largest reservoir east of the Mississippi River, so a dam break could produce catastrophic results in Middle Tennessee. If the dam were to break, the Corps estimates the flood damage would top $3 billion.

To reduce the risk of a dam failure, the Corps made an emergency decision last month to drop water levels to 680 feet for the remainder of the year. In September and October, officials will reevaluate the situation to determine operation levels for 2008.

Normal summer levels at the lake are 720 feet. While the decrease will reduce stress on the dam, there is concern that additional lowering of water levels could adversely impact communities that draw their water supplies from the lake. These concerns regarding water supply certainly have merit, but the focus must remain on ensuring the safety of residents who live downstream. The Corps has stressed that the dam is in no immediate danger of breaking, but it is important for the agency to be cautious and take prudent measures to reduce the risk once and for all.

The seepage problems are not new. In the 1960s, the Corps realized that seepage at Wolf Creek Dam was posing a serious threat to the dam’s integrity. A grouting program was put in place to solve the problem, but more repairs were needed. The most recent rehabilitation to the dam occurred in the 1970s when a concrete cut-off wall was installed to control seepage at the foundation. Unfortunately, the problem has persisted to a dangerous level, causing wet areas downstream and increased water pressure at some locations.

The current $300 million rehabilitation plan calls for more grouting and installation of a new cut-off wall into rock foundation of the dam to defend against future seepage. There is hope that implementing new technology will address the problems that have plagued the 54-year-old dam. Construction is expected to be completed by 2014.

I will continue to monitor the Corps’ progress throughout the rehabilitation. In the meantime, I encourage residents to attend the upcoming public meetings regarding the repairs. They will be held Feb. 12 at the Hendersonville First Baptist Church Chapel and Feb. 15 at Gallatin City Hall. Both meetings are scheduled from 6:30 p.m. to 8 p.m.