Nickajack Lake is managed by Tennessee Valley Authority (TVA). Lake Insights displays its latest available elevation from NOAA / National Weather Service — Advanced Hydrologic Prediction Service. Published reference elevations are listed below.
Lake Status
1.4 feet below full pool
−1.40 ft vs full pool
- 7-day trend
- Falling
- 7-day change
- Up 0.59 ft
- 30-day change
- Up 0.88 ft
- Last updated
- 1 hour ago
Nickajack Lake is currently 1.4 feet below full pool and has fallen slightly over the past week. Readings show continued drawdown relative to full pool, with levels trending lower over the past week.
Watershed drought conditions
Marion County, TN · surrounding county from lake location
Abnormally Dry
The surrounding county is abnormally dry, which is not official drought.
Severity
Weekly trend
Worsening
Compared with last week
Official drought
No
Current conditions are classified as Abnormally Dry (D0), which is not considered official drought.
U.S. Drought Monitor · map date Sep 15, 2026. Updated weekly. droughtmonitor.unl.eduView drought map for Marion County, TN
Key Facts
Managing authority
Waterbody / project type
Official purposes
Full pool
Winter pool
Current-level source
Project / NID identifier
Dam / watershed (NID design values)
Static design values from a confidently matched National Inventory of Dams record — not live gage readings.
- Normal storage
- 240,800 acre-ft
- Max storage
- 251,600 acre-ft
- Surface area at normal pool
- 10,200 acres
- Drainage area
- 21,870 sq mi
- Spillway capacity (design)
- 501,900 cfs
- Dam structure
- Concrete · 81 ft high · completed 1967
- Hazard classification
- High
- Safety & inspection
- last inspection Sep 30, 2024
National Inventory of Dams · matched record: Nickajack Dam (TN11502)
How this lake is operated
- Documented project purposes (National Inventory of Dams): Hydroelectric, Navigation, Recreation, Water Supply.
Why the level can change
General factors for reservoirs like this
These are common influences for this type of lake. They do not identify the cause of a specific current change unless an operator update confirms it.
Rainfall & inflows
Rain and upstream river inflows can raise reservoir levels, especially after storms.
Downstream releases
When an operator releases water through a dam, reservoir storage can fall and downstream flows can rise.
Flood-risk operations
Some projects store or release water under flood-risk rules when conditions require it.
Water supply
Some reservoirs support municipal, industrial, irrigation, or regional water-supply needs.
Hydropower
Hydropower projects may pass water through turbines when generating electricity.
Seasonal weather
Dry periods, heat, evaporation, and seasonal rainfall patterns can affect storage over weeks and months.
Published reference elevations
- Full pool
- 634.00 ft
- Winter / seasonal pool
- 632.00 ft
Published reference elevation. Not necessarily a fixed year-round target for every project.
A winter / seasonal pool elevation is published, but Lake Insights does not have verified seasonal operating dates for this lake.
Current data source
Managing authority: Tennessee Valley Authority (TVA)
Observation source used by Lake Insights: NOAA / National Weather Service — Advanced Hydrologic Prediction Service
Who manages the lake and who publishes the reading Lake Insights displays can differ. Lake Insights does not invent a source label from the managing authority alone.
General education
Shared background — not lake-specific facts
Lake Insights aggregates water level information from authoritative public sources such as the U.S. Army Corps of Engineers, NOAA, TVA, Bureau of Reclamation, power utilities, and other official lake operators. We preserve historical observations, calculate trends, and present lake conditions in a consistent format. For NOAA / National Weather Service — Advanced Hydrologic Prediction Service, we link to the official source whenever it is available. Lake Insights does not predict future lake levels unless an official forecast has been published by the managing authority.
Common questions about Nickajack Lake
- Who manages Nickajack Lake?
- Nickajack Lake is managed by Tennessee Valley Authority (TVA). Lake Insights reports published gauge readings; it does not operate the waterbody.
- What is full pool at Nickajack Lake?
- The published full-pool elevation for Nickajack Lake is 634.00 ft. Full pool is a published reference elevation — not a prediction of today’s level.
- Does Nickajack Lake have a published winter pool?
- Nickajack Lake has a published winter / seasonal pool elevation of 632.00 ft. Lake Insights does not currently have verified seasonal operating dates for this lake.
- Where does Lake Insights get the level reading for Nickajack Lake?
- Lake Insights displays the latest available elevation for Nickajack Lake from NOAA / National Weather Service — Advanced Hydrologic Prediction Service. The managing authority (Tennessee Valley Authority (TVA)) may differ from the agency that publishes the observation used on this page.
- What are the documented purposes of Nickajack Lake?
- Documented purposes for Nickajack Lake (National Inventory of Dams): Hydroelectric, Navigation, Recreation, Water Supply.