By Marcia Barnes
Clay County Progress
The Tennessee Valley Authority posted a new map on the TVA website showing what water levels could look like at the Lake Chatuge reservoir during two potential winter draw-downs that would allow for work to fix the spillway at the dam on Sept. 5.
Simultaneously, the TVA sent postcards to property owners within a 1-mile radius of the reservoir. The postcards were sent to 4,300 property owners in Clay County and to 7,206 property owners in Towns County, Ga. Postcards were also mailed to property owners who reside out of state.
The new graphics of draw-downs on Chatuge reservoir and a new video in which TVA Dam Safety Project Manager Chris Saucier explains the graphics in some detail are a part of the information posted. The Chatuge Dam Safety Project Public Scoping report was also posted and the public can access the new graphics, video and report at tva.com/Chatuge.
A bathymetry study was conducted at Chatuge this summer and TVA has posted an interactive map at tva.com/Chatuge that allows residents and businesses near the reservoir to find where TVA expects the edge of the water line to be during draw-downs.
There is also an updated graphic showing that while TVA plans to return the reservoir to normal operations around the beginning of spring, barring any unforeseen circumstances, the ability to return the reservoir to normal summer pool will be wholly dependent on the amount of rainfall in the area.
The recently released information responds to public requests and questions received during the environmental scoping period which ended May 28. The post card tells how to find the draw-down contour data for the proposed Chatuge Dam Safety Modifications Project.
A safety study at the Chatuge Dam was brought about by the failure of the spillway at Oroville Dam in California in February 2017. There was an extreme amount of water flowing over the Oroville spillway during a heavy rain event. In a very extreme flood event, water flows on the dam spillway at a high velocity and with spillways like the ones at Oroville and Chatuge, there is a possibility that water can be injected into the joints between the concrete slabs, lift them out and ultimately cause a failure.
In early spring, TVA established four options for potential actions to fix the 83-year-old Chatuge Dam and address the spillway concerns. The options required seasonal draw-downs to ensure that the reservoir could still provide flood control and ensure the safety of those working at the project site.
In May, the TVA provided two open house meetings in order to gather public input on the proposed safety modifications to the Chatuge Dam spillway. Three hundred people attended the meeting in Hayesville on May 8. The TVA public meeting on May 13 in Young Harris, Ga., had 315 attendees.
The information gathering period also included two virtual meetings and gave private citizens, business owners and public officials access to comment directly to the TVA on the environmental and economic impacts of the proposed modifications. Comments received during the public scoping period, which continued through May 28, can be viewed online in the document report.
TVA recently eliminated an option which required the longest draw-down. The remaining three options would require two draw-downs in the tourism off-season during the fall and winter to 1908 feet, which is 10 feet below the normal winter pool. The two off-season draw-downs could occur in two consecutive years or they could occur in two non-consecutive years.
Work at the spillway site would not begin before 2027 and early 2028 is more likely. TVA has performed surveys to assess the depth of the Chatuge reservoir. These surveys show how a draw-down to a 1,908 elevation may affect water levels throughout the reservoir potentially impacting marinas, boat ramps and private docks.
An analysis of potential environmental effects from a draw-down will be published in the draft Environmental Impact Statement scheduled for release next year.