The 50 largest wastewater treatment plants in Vermont
Ranked by average flow · 14 MGD combined · 100% of the state's reported flow
Bennington Wastewater Treatment Facility in Bennington is the largest publicly owned wastewater treatment plant in Vermont by reported average flow, treating about 2.53 million gallons per day. The 50 plants below treat 14 MGD between them, 100% of the flow reported by all 64 plants in the state, and serve about 143,495 people. Every plant links to its profile with permit, technology and compliance data.
| # | Facility | City | Avg flow (MGD) | Population | NPDES permit | Expires | Technology | Violations (3y) |
|---|---|---|---|---|---|---|---|---|
| 1 | Bennington Wastewater Treatment Facility | Bennington | 2.53 | 15,333 | VT0100021 | Jun 2029 | Biogas silos | 7 |
| 2 | St Albans City | St Albans | 1.77 | 7,876 | VT0100323 | Sep 2022 | Clarifiers, Uncovered lagoons, Biogas silos | 18 |
| 3 | Essex Junction Wastewater Treatment Facility | Essex Junction | 1.67 | 19,080 | VT0100111 | Jun 2026 | Clarifiers, Aerated lagoons, Biogas silos, Biogas balloons | 2 |
| 4 | Montpelier Wastewater Treatment Facility | Montpelier | 1.22 | 10,429 | VT0100196 | Sep 2022 | Clarifiers, Biogas silos, Biogas balloons | 0 |
| 5 | St Johnsbury | St Johnsbury | 0.95 | 5,800 | VT0100579 | Mar 2023 | Clarifiers, Biogas silos | 18 |
| 6 | Springfield Wastewater Treatment Facility | Springfield | 0.6 | 8,812 | VT0100374 | Sep 2020 | Clarifiers, Biogas silos | 18 |
| 7 | Winooski Sewage Treatment Plant | Winooski | 0.46 | 6,853 | VT0100510 | Jun 2026 | Clarifiers | 0 |
| 8 | Waterbury WWTP | Waterbury | 0.39 | 1,807 | VT0100463 | Dec 2025 | Aerated lagoons | 1 |
| 9 | Northfield Wastewater Treatment Facility | Northfield | 0.33 | 4,424 | VT0100242 | Sep 2025 | Biogas silos | 18 |
| 10 | Stowe WPCF | Stowe | 0.28 | 1,848 | VT0100455 | Sep 2025 | Biogas balloons | 85 |
| 11 | Champlain Water District | So Burlington | 0.25 | — | VT0020729 | Mar 2016 | — | 1 |
| 12 | Milton W P C | Milton | 0.25 | 3,409 | VT0100684 | Jun 2023 | — | 0 |
| 13 | Morrisville WPCF | Morrisville | 0.23 | 3,146 | VT0100480 | Jun 2023 | — | 1 |
| 14 | Wastewater Treatment Facility #2 | Shelburne | 0.23 | 2,074 | VT0100820 | Dec 2022 | — | 43 |
| 15 | Brandon WWTF | Brandon | 0.22 | 3,205 | VT0100056 | Mar 2027 | Clarifiers, Aerated lagoons, Carrousels / oxidation ditches | 12 |
| 16 | Swanton Village Wastewater Treatment Facility | Swanton | 0.22 | 3,593 | VT0100501 | Jun 2023 | Aerated lagoons, Biogas balloons | 13 |
| 17 | Manchester Town Water & Sewer Dept | Manchester | 0.18 | 2,464 | VT0100170 | Sep 2023 | Aerated lagoons | 0 |
| 18 | Randolph | Randolph | 0.17 | 2,715 | VT0100285 | Sep 2020 | Uncovered lagoons | 240 |
| 19 | Wastewater Treatment Facility No 1 | Shelburne | 0.17 | 3,031 | VT0100331 | Sep 2022 | Aerated lagoons | 25 |
| 20 | Castleton Wastewater Treatment Facility | Castleton | 0.17 | 3,663 | VT0100897 | Jun 2024 | Biogas balloons | 0 |
| 21 | West Rutland | West Rutland | 0.13 | 2,574 | VT0100714 | Sep 2027 | Clarifiers | 2 |
| 22 | Hinesburg Wastewater Treatment Facility | Hinesburg | 0.11 | 2,300 | VT0101028 | Sep 2028 | Aerated lagoons, Uncovered lagoons | 71 |
| 23 | Hartford - Quechee | Hartford | 0.11 | 905 | VT0100978 | Sep 2024 | — | 72 |
| 24 | Ludlow Wastewater Treatment Facility | Ludlow | 0.1 | 1,885 | VT0100145 | Dec 2019 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches | 24 |
| 25 | Proctor Wastewater Treatment Facility | Proctor | 0.08 | 2,113 | VT0100528 | Dec 2027 | Aerated lagoons | 25 |
| 26 | Swanton Village Water Treatment Plant | Swanton | 0.08 | — | VT0020877 | Mar 2024 | — | 1 |
| 27 | Richmond Wastewater Treatment Facility | Richmond | 0.07 | 1,714 | VT0100617 | Dec 2025 | — | 2 |
| 28 | Williamstown WPCF | Williamstown | 0.07 | 1,814 | VT0100722 | Dec 2022 | Aerated lagoons | 2 |
| 29 | Pownal | North Pownal | 0.06 | 1,766 | VT0101281 | Mar 2023 | — | 0 |
| 30 | Troy/jay WWTF | Jay | 0.06 | 2,118 | VT0101168 | Jun 2023 | Uncovered lagoons | 9 |
| 31 | Wilmington WWTP | Wilmington | 0.05 | 1,134 | VT0100706 | Sep 2023 | Aerated lagoons | 5 |
| 32 | Johnson WPC | Johnson | 0.05 | 3,361 | VT0100901 | Jun 2023 | — | 0 |
| 33 | Barton Wastewater Treatment Facility | Barton | 0.04 | 2,145 | VT0100641 | Mar 2024 | Aerated lagoons | 16 |
| 34 | Fairfax Wastewater Treatment Facility | Fairfax | 0.04 | 1,037 | VT0101087 | Jun 2023 | Aerated lagoons | 133 |
| 35 | Village Of North Troy Mtp | North Troy | 0.04 | 607 | VT0100234 | Jun 2023 | — | 57 |
| 36 | Bethel | Bethel | 0.04 | 885 | VT0100048 | Dec 2027 | Clarifiers, Carrousels / oxidation ditches | 1 |
| 37 | Saxtons River Wastewater Treatment Facility | Saxtons River | 0.04 | 985 | VT0100609 | Dec 2022 | — | 0 |
| 38 | Orleans Wastewater Treatment Facility | Orleans | 0.04 | 1,265 | VT0100251 | Mar 2024 | Clarifiers, Uncovered lagoons | 93 |
| 39 | Royalton WWTF | South Royalton | 0.03 | 440 | VT0100854 | Jun 2024 | Aerated lagoons, Uncovered lagoons | 0 |
| 40 | North Hero Water Treatment Facility | North Hero | 0.03 | — | VT0101231 | Mar 2025 | — | 3 |
| 41 | Plainfield Wastewater Treatment Facility | Plainfield | 0.03 | 724 | VT0100781 | Sep 2025 | — | 84 |
| 42 | Richford Wastewater Treatment Facility | Richford | 0.03 | 728 | VT0100790 | Jun 2023 | Aerated lagoons | 83 |
| 43 | Jeffersonville W W T F | Vergennes | 0.02 | 585 | VT0101150 | Jun 2023 | Aerated lagoons | 30 |
| 44 | Pittsford Wastewater Treatment Facility | Pittsford | 0.02 | 914 | VT0100692 | Mar 2027 | — | 0 |
| 45 | Whitingham (jacksonville) | Jacksonville | 0.02 | 414 | VT0101044 | Jun 2028 | — | 100 |
| 46 | Vt Correctional Ind | St Albans | 0.02 | 174 | VT0101117 | Sep 2022 | — | 2 |
| 47 | Cabot WWTF | Cabot | 0.02 | 411 | VT0101257 | Sep 2025 | — | 4 |
| 48 | Marshfield Wastewater Treatment Facility | Marshfield | 0.02 | 472 | VT0100471 | Dec 2025 | Aerated lagoons | 7 |
| 49 | Readsboro WPC | Readsboro | 0.01 | 309 | VT0100731 | Mar 2028 | Aerated lagoons | 2 |
| 50 | Benson Town WWTP | Benson | 0.0084 | 154 | VT0100498 | Jun 2024 | — | 5 |
Largest plants in Vermont: 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 September 11, 2026.