The Corps of Engineers seeks bids for installation of a grout curtain seepage barrier at 135-MW Center Hill Dam in Dekalb County, Tenn. Proposals are due Sept. 6.
The Corps issued a solicitation following a call for expressions of interest. (HNN 5/7/07) It estimates the cost of work over a two-year contract period will range from $50 million to $100 million. The Corps could award the contact in September and issue a notice to proceed by the end of December.
The 250-foot-tall dam consists of a 1,382-foot-long concrete section and 778-foot-long earth embankment.
The contractor is to install an 800-foot-long grout curtain into the rock foundation of the main dam embankment; build a work surface near the crest of the earthen embankment portion of the dam; and install a 3,500-foot-long grout curtain into the rock foundation at the left rim of the dam. It also would plug an area beneath the grout line on the left rim.
Center Hill Dam, on the Caney Fork River near Lancaster, Tenn., has a history of seepage problems that have worsened in recent years. It is among six dams the Corps identified as having a high risk of failure, in a screening program of 130 dams. (HNN 5/2/07)
The Corps already has lowered the reservoir to the lower end of its operating range. In 2006, the Corps approved a $240 million rehabilitation plan that includes the grouting work. The government said work to improve the dam’s long-term reliability could be completed in 2014.
The solicitation, No. W912P5-07-R-0004, is available from the Federal Technical Data Solutions (FedTeDS) Internet site, www.fedteds.gov. Geotechnical data is available on compact disk from the Corps’ Nashville District, by contacting John Grayson, E-mail: firstname.lastname@example.org. Bidders must register on the government’s Central Contractor Registration Internet site, www.ccr.gov.