Hardin County, Tennessee
In September 2016, TVA completed a final Environmental Assessment (EA) and Finding of No Significant Impact (FONSI) to document the potential effects of TVA's upgrades to the south embankment of Pickwick Landing Dam to improve performance of the dam during and following a large earthquake. These documents can be viewed below on this page below under "Related Documents".
Since the EA was completed, there have been changes to the design to reduce overall risks to the integrity of the dam during construction and to address construction challenges. On January 9, 2019, TVA issued a final supplemental environmental assessment and FONSI for the proposed changes to implement the necessary design changes to complete its upgrades at Pickwick Landing Dam. The proposed actions in the SEA resulting in additional area of impact include:
TVA published a draft supplemental EA in October 2018 for public review and comment. TVA received a total of 3 comment letters; 2 from the State of Tennessee Department of Environment and Conservation and 1 from the National Park Service-Shiloh National Military Park. Â TVA responded to these comments in the final supplemental EA.
The EA and Finding of No Significant Impacts completed in September 2016 addressed TVA's proposed upgrades of the south embankment of Pickwick Landing Dam to improve performance of the dam during and following a large earthquake. A seismic stability evaluation of the embankment completed in 2014 indicates that a large earthquake could result in the loss of strength in some soil layers of the embankment, leading to slope instability and the breach of the dam. TVA informed the public of this potential and installed an early warning system in 2015 and began developing a proposal to strengthen the dam's embankment.
Upgrades would be made to both the upstream and downstream sides of the earthen embankment. Berms would be constructed along the toe of each side of the embankment and areas of extended fill would be placed in select locations. Under the proposal, a small area of TVA land along North Carolina Landing Road below the dam would be used for construction laydown activities. Activities would not close or restrict travel on Highway 128 crossing the dam. TVA does not propose to change its operation of the reservoir during construction (i.e., lake levels would continue to follow the existing seasonal patterns). The upgrades to the embankment would allow TVA to avoid risk to public health and safety and the significant economic impacts that would result from having to lower the reservoir below winter pool levels for an extended period following an emergency.
More information on this environmental review can be obtained from: