40 plants · 18% of the state · 69 MGD reported by 37 plants
Klarifi identifies 40 publicly owned wastewater treatment plants with oxidation ditches in Tennessee, 18% of the 227 plants in the state (69 MGD reported by 37 plants). The largest is City Of Cookeville Department Of Water Quality Control (wwtp) in Cookeville at 9.62 MGD.
Oxidation ditches are ring-shaped activated sludge reactors with long retention times, common at plants between 0.5 and 10 MGD. They are recognisable from the air by their looped channels and rely on surface aerators or brush rotors, which are frequent replacement and energy-efficiency projects.
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | City Of Cookeville Department Of Water Quality Control (wwtp) | Cookeville | 9.62 | TN0024198 | Jun 2027 | 27 |
| 2 | City Of Franklin Wastewater Treatment Plant | Franklin | 7.12 | TN0028827 | Dec 2026 | 44 |
| 3 | Sevierville (mccroskey Island) STP | Sevierville | 5.32 | TN0063959 | Apr 2030 | 115 |
| 4 | Harpeth Valley Utility District STP | Nashville | 4.76 | TN0074748 | Feb 2030 | 4 |
| 5 | Hallsdale-Powell U.D.-Melton Hill Lk | Knoxville | 4.48 | TN0078905 | Sep 2028 | 44 |
| 6 | City Of Spring Hill STP | Spring Hill | 3.65 | TN0075868 | Dec 2028 | 42 |
| 7 | Collierville Northwest STP | Collierville | 3.38 | TN0078841 | Jan 2028 | 3 |
| 8 | Denzil Bowman Wastewater Treatment Plant (greeneville Stp) | Greeneville | 3.34 | TN0021229 | Oct 2030 | 28 |
| 9 | Knob Creek Waste Water Plant | Johnson City | 3.07 | TN0024236 | Sep 2026 | 17 |
| 10 | Shelbyville Wastewater Treatment Plant | Shelbyville | 3.04 | TN0024180 | Jan 2029 | 22 |
| 11 | Crossville STP | Crossville | 2.61 | TN0024996 | Dec 2026 | 26 |
| 12 | Manchester STP | Manchester | 2.15 | TN0025038 | Feb 2029 | 40 |
| 13 | Dickson STP | Dickson | 2 | TN0066958 | Dec 2026 | 21 |
| 14 | Elizabethton WWTP | Elizabethton | 1.8 | TN0023515 | Aug 2031 | 18 |
| 15 | Lenoir City STP | Lenoir City | 1.43 | TN0020494 | Jul 2031 | 11 |
| 16 | Martin STP | Martin | 1.21 | TN0062545 | May 2030 | 20 |
| 17 | Mcminnville Wastewater Plant | Mcminnville | 1.21 | TN0023591 | Jan 2028 | 4 |
| 18 | Town Of Collierville | Collierville | 1.16 | TN0057461 | Dec 2028 | 5 |
| 19 | Covington Wastewater Treatment Plant | Covington | 1.01 | TN0020982 | Mar 2029 | 1 |
| 20 | Town Of Jonesborough Dba Pliny Fisk Composting And Recycling Center | Jonesboro | 0.69 | TN0081175 | Jun 2030 | 13 |
| 21 | Etowah Utilities Board Dba Etowah Utilities Wastewater Treatment Plant | Etowah | 0.69 | TN0063771 | May 2027 | 17 |
| 22 | Woodbury STP | Woodbury | 0.63 | TN0025089 | Jul 2031 | 31 |
| 23 | Tellico Area Services System - Niles Ferry STP | Vonore | 0.5 | TN0058238 | Oct 2028 | 2 |
| 24 | Wartburg STP | Wartburg | 0.46 | TN0028622 | Jul 2026 | 18 |
| 25 | City Of Kingston | Kingston | 0.44 | TN0061701 | Aug 2028 | 15 |
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.
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 September 11, 2026.