Activated sludge and clarifiers: wastewater treatment plants in Tennessee
82 plants · 34% of the state · 334 MGD reported by 78 plants
Klarifi identifies 82 publicly owned wastewater treatment plants with activated sludge and clarifiers in Tennessee, 34% of the 243 plants in the state (334 MGD reported by 78 plants). The largest is Metro Central Wastewater Treatment Plant in Nashville at 103.22 MGD.
Activated sludge is the standard mechanical process for cities: aeration basins where bacteria consume organic matter, followed by clarifiers that settle the biomass out. These plants are identified by their circular or rectangular clarifiers and by the suspended-growth process code, and they are the main market for blowers, diffusers, clarifier mechanisms and instrumentation.
The largest activated sludge plants in Tennessee
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | Metro Central Wastewater Treatment Plant | Nashville | 103.22 | TNL020575 | Dec 2030 | 63 |
| 2 | Moccasin Bend Wastewater Treatment Plant | Chattanooga | 50.56 | TNR053775 | Jun 2030 | 52 |
| 3 | Whites Creek Wastewater Treatment Plant | Nashville | 32.64 | TN0024970 | Oct 2025 | 40 |
| 4 | Nashville Dry Creek STP | Madison | 16.24 | TN0020648 | Oct 2025 | 34 |
| 5 | City Of Cookeville Department Of Water Quality Control (wwtp) | Cookeville | 10.75 | TN0024198 | Jun 2027 | 27 |
| 6 | City Of Franklin Wastewater Treatment Plant | Franklin | 9.77 | TN0028827 | Dec 2026 | 44 |
| 7 | Cleveland Utilities Wastewater Treatment Plant | Charleston | 8.48 | TN0024121 | Apr 2027 | 44 |
| 8 | Hallsdale-Powell U.D.-Melton Hill Lk | Knoxville | 6.35 | TN0078905 | Sep 2028 | 44 |
| 9 | Johnson City STP | Johnson City | 5.94 | TN0024244 | Sep 2026 | 18 |
| 10 | Harpeth Valley Utility District STP | Nashville | 5.88 | TN0074748 | Feb 2030 | 4 |
Contacts and project signals for every plant on this list
Klarifi adds verified decision-maker contacts, permit limits, discharge monitoring data and the capital projects planned in each city, filterable by technology, size and compliance record.
Other technologies in Tennessee
Activated sludge and clarifiers in other states
Activated sludge and clarifiers in Tennessee: questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed October 26, 2026.
Wastewater terms: Activated sludge · Biological nutrient removal · Equalization tank · MGD · Lift station · all terms