As we enter the Memorial Day weekend, TVA is providing a brief update on drought conditions across the Tennessee Valley and associated impacts to lake levels.
TVA’s public lakes and waterways are open for recreation and enjoyment throughout the summer – some look a bit different this year. With most tributary reservoirs below their target “summer pool” elevations, users are reminded to prioritize safety and remain mindful of hazards that may be exposed or closer to the surface than in most summers. Our reservoirs are regularly utilized by boaters and anglers during the winter months, and it’s worth noting that current water levels are well above “winter pool” elevations.
The latest version of the drought monitor (May 21) shows the entire Tennessee River watershed remains in some degree of drought. 73% of the Valley region is in at least Severe Drought, and 41% of the Valley region is in Extreme Drought. Calendar-year-to-date rainfall is 70% of normal, while runoff is 45% of normal in the Tennessee Valley.
TVA’s River Forecast Center balances competing demands on the Tennessee River system, including flood damage reduction, navigation, power production, water supply, water quality and recreation. The recreation piece is often at the forefront of the public’s mind, especially at this time of year.
For the past several months, TVA’s operating posture has been conservative as drought conditions have developed and expanded. We have been releasing minimal water through the system to meet minimum flow commitments and downstream demands.
A return to normal rainfall will not quickly resolve drought conditions. For example, while we expect to see rainfall even this week, many weeks and months of normal rainfall is needed to return to normal inflow conditions. Typically, during the summer months, there is minimal inflow into TVA reservoirs because of evaporation, dry soil and vegetation, and other hydrologic losses. In order to get to summer pool each year, TVA relies on January-March rainfall and subsequent runoff – Mother Nature provided very little of that this year.
2-4 inches of rainfall is predicted across the Valley over the next several days. The majority of that rain is forecast to fall on the western side of the Valley and is not expected to provide significant runoff or drought relief, as the dry soil and root systems of lawns, trees and other vegetation will absorb the vast majority of that water.
Below are updated details on specific main-river and tributary reservoirs throughout the system. Generally speaking, large tributary reservoirs are well below target summer levels and would need significantly above-normal rainfall for numerous months to reach their “full” summer targets.
Main River Status
- Fort Loudoun, Watts Bar and Chickamauga are below normal operating range for this time of year.
- Nickajack, Guntersville, Wheeler, Wilson, Pickwick and Kentucky are in normal operating range for this time of year.
- The upper main stem river will require several inches of rainfall to reach normal summer operating levels.
- Flows along the main river are near minimal levels to meet minimum flow commitments.
South Holston, Watauga, Boone, Fort Patrick Henry*
- South Holston reservoir remains 4 feet below target elevation for this time of year and is expected to begin falling in June as releases are made for downstream flow requirements.
- Boone reservoir remains about 6.5 feet below normal elevation for this time of year and would need above normal rainfall to reach summer pool by early June.
- Watauga is near target elevation and is expected to begin falling as releases are made for downstream flow requirements.
*Fort Patrick Henry maintains a constant reservoir level all year.
Cherokee, Douglas, Fontana and Norris
- Cherokee reservoir is about 11 feet below target elevation for this time of year and is expected to remain near its current level into early June.
- Douglas reservoir is about 15 feet below target elevations for this time of year and is expected to remain near its current level into early June.
- Fontana reservoir is 21 feet below target elevation for this time of year and is expected to remain near its current level into early June.
- Norris reservoir is about 9 feet below target elevation for this time of year and is expected to remain near its current level into early June.
Chatuge, Nottely, Hiwassee, Blue Ridge
Chatuge, Nottely, Hiwassee, Blue Ridge
- Chatuge reservoir is about 2 feet below target elevation for this time of year and is expected to remain near its current level into early June.
- Blue Ridge reservoir is about 2 feet below target elevation for this time of year and is expected to remain near its current level into early June.
- Nottely reservoir is about 7 feet below target elevation for this time of year and is expected to remain near its current level into early June.
- Hiwassee reservoir is about 14-15 feet below target elevation for this time of year and is expected to remain near its current level into early June.
Other resources:
