Currently, three issues are relevant:
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Current status of the dam fix
The Corps of Engineers, Nashville District is currently implementing a plan to address serious foundation seepage issues at Center Hill Dam. The purpose of the ongoing construction is to ensure the long term reliability of the dam. The total project rehabilitation began in 2008 and is scheduled to be completed in 2019. Three large construction contracts are planned. The first two major contracts addressed the earthen embankment of the main dam and the left rim (to the southwest of the dam). Grout, a flowable concrete mix, was placed into the foundation rock beneath and beside the dam from 2008 to 2010 to fill solution features, to gather information about the rock, and to prepare the foundation for construction of a deep foundation barrier wall. The barrier wall was constructed 2012 to 2105. An approximate 2.5-foot thick concrete wall was constructed into the earthen embankment up to 310 feet of depth from the top of the dam. The wall is a permanent long term seepage barrier. Final contract demobilization and closeout activities are currently underway. The final major construction is planned to protect the earthen saddle dam which fills a low area in the topography just east of the main dam. A concrete reinforcing berm is planned to be built downstream of the saddle dam from 2016 through 2018 to complete the overall rehabilitation efforts. Throughout construction we continue to closely monitor the dam.
- Lake levels throughout construction
Maintaining lower lake elevations is necessary to keep high pressures off the dam embankments during construction and also to facilitate lowering the lake in the event of an emergency. The project will be reassessed when enough of the construction is complete to lower risk, estimated late 2018. At that time we will determine the appropriate lake levels for the future. We anticipate lake levels will return to normal.
During construction, the Corps has targeted Center Hill Lake levels between elevation 630 feet above mean sea level (msl) in the summer and no lower than elevation 618 msl during the late fall and early winter. These elevations are approximately fifteen to twenty feet lower than preconstruction lake operating levels. The chosen levels are the result of an Environmental Impact Statement (EIS) developed in 2007 and included consideration of safety concerns, potential impact to project purposes, and the views of the State of Tennessee, other federal agencies, affected stakeholders, and the public. The goal of the EIS was to identify an alternative that balanced the safety of the downstream human and natural environment against the reduction of project benefits from water supply, water quality, recreation, navigation, and hydropower.
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Emergency action and information
Although not anticipated, there are events that could cause the Corps to lower the lake as an emergency action. Also, your County Emergency Managers have maps of areas which could flood if Center Hill Dam were to fail. The Corps has an aggressive Dam Safety program to constantly monitor all of our dams in the Cumberland River system and Center Hill is being monitored constantly. The Corps will use news articles, websites, and public meetings to keep the public informed of the dam’s condition and of progress of the foundation remedy throughout construction.
Accurate and timely information is critical to the effective resolution of many issues associated with Corps of Engineers projects. This web site has been established to provide information you need to stay informed. The site will be updated, based on the needs of our site visitors. Please let us know what you need. Please share this site with others interested in this project.