Review of TVA's Reservoir Operations Program

Based upon questions posed to OIG personnel regarding TVA's criteria for the adjustment of tributary water levels, the OIG conducted a review of TVA's Reservoir Operations. Our objectives were to determine (1) whether criteria exist to balance the competing objectives of managing water in TVA reservoirs, (2) how those objectives compare to those of the U.S. Army Corps of Engineers, and (3) whether TVA was following its criteria. This report encompasses TVA-managed lakes, tributaries, and overall Reservoir Operations.Our review found TVA has Board-approved guidelines that were developed with public input in 2004. We noted in discussion with two offices of the U.S. Army Corps of Engineers that they balance similar objectives and manage their reservoirs in a like manner as TVA. We performed testing based upon the approved TVA guidelines and found no issues. Specifically, we found that there were no issues related to the following summer criteria: (1) Recreational Releases (releases water to enhance recreation opportunities). (2) Chickamauga Flow (the required flow through Chickamauga Dam). (3) Tributary Balancing (ensuring that no individual tributary is disproportionately affected when meeting river system minimum flow goals). Lastly, we found there were no issues related to the following nonsummer criteria: (1) Minimum Flow Commitments, which is measured in pulse commitment violations (a pulse represents a release of an agreed-upon amount of water, and a violation is an instance where TVA does not provide the pulse on time). (2) Flood Storage Availability (flood storage is defined as the volume, or capacity, in a reservoir that is reserved for the storage of flood water, and anytime a tributary's headwater elevation exceeds the flood guide, it is in violation). Since we had no recommendations, this report was issued for informational purposes only.