The largest US wastewater treatment plants with anaerobic digesters
Ranked by average flow · 5,210 MGD combined
Deer Island Wastewater Treatment Facility in Winthrop, Massachusetts tops the list at about 233.7 million gallons per day. New York (17), Texas (12), New Jersey (7), California (6), Ohio (6) have the most plants in the top 100. Every plant links to its profile with permit, technology and compliance data.
Anaerobic digesters stabilise sludge and produce biogas, and the plants that have them are the market for mixing, heating, gas cleaning, cogeneration and dewatering equipment. This list ranks the largest plants where Klarifi’s aerial imagery review finds digester silos or gas holders, or where the EPA needs survey records anaerobic digestion.
| # | Facility | City | State | Avg flow (MGD) | NPDES permit | Expires | Technology | Violations (3y) |
|---|---|---|---|---|---|---|---|---|
| 1 | Deer Island Wastewater Treatment Facility | Winthrop | MA | 233.7 | MA0103284 | Jul 2005 | Biogas silos, Biogas balloons | 3 |
| 2 | Central District Wastewater Treatment Plant | Key Biscayne | FL | 194.6 | FL0024805 | Dec 2025 | Biogas silos, Biogas balloons | 67 |
| 3 | Newtown Creek Water Pollution Control Plant | Brooklyn | NY | 188 | NY0026204 | Jun 2027 | Clarifiers, Biogas silos, Biogas balloons | 5 |
| 4 | Met Council Metropolitan WWTP | Saint Paul | MN | 180 | MNL029815 | Dec 2030 | Biogas silos | 0 |
| 5 | NYC-DEP Wards Island WPCP | Manhattan | NY | 174 | NY0026131 | Jun 2027 | Clarifiers, Biogas silos | 25 |
| 6 | MWRDGC Terrence J O'Brien Water Reclamation Plant | Skokie | IL | 170 | IL0028088 | Jul 2022 | Clarifiers, Biogas balloons | 18 |
| 7 | Village Creek Reclamation Facility | Arlington | TX | 142 | TX0047295 | Jan 2029 | Clarifiers, Biogas silos, Biogas balloons | 3 |
| 8 | Point Loma Wastewater Treatment Plant | San Diego | CA | 137 | CA0107409 | Sep 2022 | Biogas silos | 1689 |
| 9 | Back River Wastewater Treatment Plant | Baltimore | MD | 114.1 | MDL021555 | Dec 2030 | Clarifiers, Uncovered lagoons, Biogas silos, Biogas balloons | 32 |
| 10 | Hunts Point Water Pollution Control Plant | Bronx | NY | 109 | NY0026191 | Jun 2027 | Clarifiers, Biogas silos | 11 |
| 11 | Dos Rios Water Recycling Center | San Antonio | TX | 105.32 | TX0077801 | Jun 2025 | Clarifiers, Aerated lagoons, Biogas silos | 48 |
| 12 | City Of Dallas Central WWTP | Dallas | TX | 104 | TX0047830 | Apr 2027 | Clarifiers, Aerated lagoons, Uncovered lagoons, Biogas silos | 10 |
| 13 | Nycdep - Bowery Bay WRRF | Astoria | NY | 94 | NY0026158 | Jun 2027 | Clarifiers, Biogas silos | 10 |
| 14 | Metropolitan St. Louis Sewer District Bissell Point WWTP | St. Louis | MO | 90.1 | MO0025178 | Aug 2031 | Clarifiers, Biogas balloons | 14 |
| 15 | Owls Head Water Pollution Control Plant | Brooklyn | NY | 88 | NY0026166 | Jun 2027 | Biogas silos | 9 |
| 16 | Indianapolis Belmont WWTP | Indianapolis | IN | 83.83 | IN0023183 | May 2029 | Biogas balloons | 116 |
| 17 | Southerly Wastewater Treatment Plant | Lockbourne | OH | 82.1 | OHL024741 | Dec 2030 | Clarifiers, Biogas silos | 7 |
| 18 | Metropolitan St. Louis Sewer District Lemay WWTP | St. Louis | MO | 79.3 | MO0025151 | Aug 2031 | Clarifiers, Biogas silos | 0 |
| 19 | 91st Avenue WWTP | Tolleson | AZ | 78.71 | AZ0020524 | Apr 2028 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches, Biogas silos | 2 |
| 20 | Southerly Wastewater Treatment Center | Cleveland | OH | 78.11 | OHL024651 | Dec 2030 | Clarifiers, Biogas balloons | 3 |
| 21 | Middlesex County Utilities Authority | Sayreville | NJ | 77.42 | NJ0020141 | Jun 2020 | Clarifiers, Uncovered lagoons, Biogas silos | 17 |
| 22 | Wilson Creek Regional Wastewater Treatment Plant | Mc Kinney | TX | 70.77 | TX0047911 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches, Biogas balloons | 24 |
| 23 | Jamaica Water Pollution Control Plant | Jamaica | NY | 70 | NY0026115 | Jun 2027 | Clarifiers, Biogas silos | 10 |
| 24 | Richmond WWTP | Richmond | VA | 63.4 | VAL063177 | Dec 2030 | Clarifiers, Biogas silos | 31 |
| 25 | Bergen County Utilities Authority | Little Ferry | NJ | 63.2 | NJ0020028 | Mar 2030 | Clarifiers, Uncovered lagoons, Biogas silos | 176 |
| 26 | Cedar Creek WPCP | Wantagh | NY | 62.2 | NY0026859 | Jan 2026 | Clarifiers, Biogas silos, Biogas balloons | 12 |
| 27 | West Boise WWTP | Garden City | ID | 62 | ID0023981 | Jun 2027 | Clarifiers, Uncovered lagoons, Biogas silos | 9 |
| 28 | Tallman Island Wastewater Treatment Plant | Queens | NY | 57 | NY0026239 | Jun 2027 | Clarifiers, Biogas balloons | 2 |
| 29 | Msd, Morris Forman Plant | Louisville | KY | 56.18 | KY0022411 | Sep 2004 | Clarifiers, Uncovered lagoons, Biogas balloons | 221 |
| 30 | Westchester Co Of - Yonkers Joint Waste Water Treatment Plant | Yonkers | NY | 55 | NY0026689 | May 2019 | Biogas silos | 29 |
| 31 | Patapsco Wastewater Treatment Plant | Baltimore | MD | 49.01 | MDL021601 | Dec 2030 | Clarifiers, Biogas silos, Biogas balloons | 22 |
| 32 | Bay Park Sewage Treatment Plant | East Rockaway | NY | 48.5 | NY0026450 | Jan 2026 | Clarifiers, Biogas balloons | 4 |
| 33 | Neuse River Resource Recovery Facility | Raleigh | NC | 47.06 | NC0029033 | Feb 2025 | Clarifiers, Aerated lagoons, Uncovered lagoons, Biogas silos, Biogas balloons | 1 |
| 34 | Ccsf- Southeast Water Pollution Control Plant | San Francisco | CA | 45.87 | CA0037664 | Sep 2018 | Clarifiers, Biogas silos | 13 |
| 35 | Albany County Sewer District - South Plant | Albany | NY | 45.11 | NY0026867 | Feb 2030 | Clarifiers, Uncovered lagoons, Biogas silos | 49 |
| 36 | Essex & Union Cnty Joint Meeting STP | Elizabeth | NJ | 44.93 | NJ0024741 | Mar 2030 | Clarifiers, Carrousels / oxidation ditches, Biogas silos | 145 |
| 37 | South Austin Regional WWTP Electrical | Del Valle | TX | 43.8 | TX0071889 | Jun 2031 | Clarifiers, Biogas balloons | 0 |
| 38 | Delaware #1 Water Pollution Control Facility | Camden | NJ | 43.19 | NJ0026182 | Dec 2029 | Biogas silos, Biogas balloons | 6 |
| 39 | NYC DEP 26 Ward WPCP | Brooklyn | NY | 43 | NY0026212 | Jun 2027 | Biogas silos | 13 |
| 40 | City Of Toledo Division Of Water Reclaimation | Toledo | OH | 39.6 | OH0027740 | Jan 2029 | Clarifiers, Uncovered lagoons, Biogas silos, Biogas balloons | 3 |
| 41 | City Of Dayton Water Reclamation Facility (0857100983) | Dayton | OH | 38.22 | OH0024881 | Apr 2027 | Clarifiers, Biogas silos, Biogas balloons | 17 |
| 42 | South Mesquite Regional Wastewater Treatment Plant | Mesquite | TX | 37.57 | TX0047431 | Aug 2027 | Clarifiers, Biogas silos | 23 |
| 43 | Moccasin Bend Wastewater Treatment Plant | Chattanooga | TN | 36.67 | TNR053775 | Jun 2030 | Clarifiers, Aerated lagoons, Uncovered lagoons, Biogas silos | 53 |
| 44 | 23rd Avenue Wastewater Treatment Plant | Phoenix | AZ | 35.67 | AZ0020559 | Jun 2029 | Clarifiers, Biogas silos | 2 |
| 45 | City Of Grand Rapids Wastewater Treatment Plant | Grand Rapids | MI | 33.4 | MI0026069 | Oct 2029 | Clarifiers, Aerated lagoons, Biogas silos, Biogas balloons | 9 |
| 46 | Augusta WWTP | Augusta | GA | 33.2 | GA0037621 | May 2024 | Clarifiers, Biogas silos, Biogas balloons | 10 |
| 47 | South Wastewater Treatment Plant | Baton Rouge | LA | 33 | LA0036412 | Jun 2029 | Clarifiers, Biogas silos, Biogas balloons | 20 |
| 48 | Roberto R Bustamante WWTP | El Paso | TX | 32.92 | TX0101605 | Apr 2030 | Clarifiers, Uncovered lagoons, Biogas silos, Biogas balloons | 35 |
| 49 | Gary Sanitary District | Gary | IN | 32.6 | IN0022977 | Jun 2027 | Clarifiers, Biogas silos, Biogas balloons | 24 |
| 50 | Pima County - Ina Road WWTP | Tucson | AZ | 31.89 | AZ0020001 | May 2027 | Clarifiers, Uncovered lagoons, Biogas silos | 3 |
| 51 | Riverside Park Water Reclamation Facility | Spokane | WA | 31.72 | WA0024473 | Aug 2027 | Clarifiers, Biogas silos | 4 |
| 52 | Salt Lake City Water Reclamation Plant | Salt Lake City | UT | 31.1 | UT0021725 | Dec 2029 | Clarifiers, Biogas silos | 1 |
| 53 | City Of Allentown Wastewater Treatment Plant | Allentown | PA | 31.07 | PA0026000 | Sep 2007 | Clarifiers, Carrousels / oxidation ditches, Biogas silos, Biogas balloons | 0 |
| 54 | Dekalb County Department Of Watershed Management (snapfinger Creek Awtf) | Decatur | GA | 30.42 | GA0024147 | Mar 2029 | Clarifiers, Biogas silos, Biogas balloons | 1 |
| 55 | Pecan Creek Water Reclamation Plant | Denton | TX | 30.27 | TX0047180 | Jul 2028 | Clarifiers, Biogas silos | 8 |
| 56 | Water Pollution Control Plant | Fort Wayne | IN | 29.9 | IN0032191 | Feb 2026 | Clarifiers, Biogas silos, Biogas balloons | 2 |
| 57 | Metro Wastewater Treatment Plant | Columbia | SC | 29.87 | SC0020940 | May 2023 | Clarifiers, Uncovered lagoons, Biogas silos | 7 |
| 58 | Little Blue Valley Sewer District | Independence | MO | 29.2 | MOL101087 | Dec 2030 | Clarifiers, Aerated lagoons, Covered lagoons, Carrousels / oxidation ditches, Biogas silos, Biogas balloons | 14 |
| 59 | Stockton Rwcf | Stockton | CA | 29.2 | CA0079138 | Jul 2030 | Clarifiers, Uncovered lagoons, Biogas silos | 57 |
| 60 | Valley Creek Wastewater Treatment Plant | Bessemer | AL | 29.2 | ALL023655 | Dec 2030 | Clarifiers, Biogas silos, Biogas balloons | 1 |
| 61 | South Bay International WWTP | San Diego | CA | 29 | CA0108928 | Jun 2026 | Clarifiers, Biogas silos | 3159 |
| 62 | Nycdep - Red Hook WPCP | Brooklyn | NY | 28 | NY0027073 | Jun 2027 | Biogas silos | 2 |
| 63 | Riverside City, Water Quality Control | Riverside | CA | 27.72 | CA0105350 | Oct 2018 | Clarifiers, Aerated lagoons, Uncovered lagoons, Biogas silos, Biogas balloons | 2 |
| 64 | Green Bay Metropolitan Sewerage District | Green Bay | WI | 27.53 | WIL065251 | Dec 2030 | Clarifiers, Carrousels / oxidation ditches, Biogas silos, Biogas balloons | 7 |
| 65 | South Columbus Water Resource Facility | Columbus | GA | 27.02 | GA0020516 | Jun 2031 | Clarifiers, Biogas silos | 2 |
| 66 | Plum Island WWTP | Charleston | SC | 27 | SC0021229 | Jul 2024 | Clarifiers, Biogas balloons | 3 |
| 67 | Wyandotte Wastewater Plant | Wyandotte | MI | 26.9 | MI0021156 | Oct 2021 | Clarifiers, Biogas silos, Biogas balloons | 5 |
| 68 | Bergen Point STP & Bergen Ave Dock | W Babylon | NY | 26.7 | NY0104809 | Dec 2019 | Clarifiers, Uncovered lagoons, Biogas silos | 81 |
| 69 | Blue Lake Wastewater Treatment Plant | Shakopee | MN | 26.54 | MN0029882 | Sep 2029 | Biogas silos, Biogas balloons | 0 |
| 70 | Sanitary District Of Decatur | Decatur | IL | 26.53 | ILL028321 | Dec 2030 | Clarifiers, Biogas silos, Biogas balloons | 1 |
| 71 | Saniatry District Of Hammond | Hammond | IN | 25.83 | IN0023060 | Apr 2027 | Clarifiers, Uncovered lagoons, Biogas silos | 21 |
| 72 | Nycdep - Oakwood Beach WPCP | Staten Island | NY | 25.4 | NY0026174 | Jun 2027 | Biogas silos, Biogas balloons | 6 |
| 73 | Southwest WWTP | Springfield | MO | 25.32 | MO0049522 | Jul 2025 | Clarifiers, Aerated lagoons, Uncovered lagoons, Carrousels / oxidation ditches, Biogas silos, Biogas balloons | 0 |
| 74 | Kalamazoo Water Reclamation Plant | Kalamazoo | MI | 24.94 | MI0023299 | Oct 2025 | Clarifiers, Biogas silos, Biogas balloons | 37 |
| 75 | Truckee Meadows Water Reclamation Facility | Reno | NV | 24.7 | NV0020150 | May 2017 | Clarifiers, Uncovered lagoons, Biogas silos | 1 |
| 76 | Willow Lake WWTP | Salem | OR | 24.62 | ORL026409 | Dec 2030 | Clarifiers, Carrousels / oxidation ditches, Biogas silos | 2 |
| 77 | Atlantic County Utilities Authority POTW | Atlantic City | NJ | 24.52 | NJL024473 | Dec 2030 | Clarifiers, Uncovered lagoons, Biogas silos | 0 |
| 78 | Jea Buckman WWTP | Jacksonville | FL | 24.34 | FL0026000 | Dec 2030 | Clarifiers, Uncovered lagoons, Biogas silos, Biogas balloons | 69 |
| 79 | South Cobb WRF | Mableton | GA | 24.28 | GA0026158 | Jun 2027 | Clarifiers, Biogas silos | 3 |
| 80 | Encina Water Pollution Control Facility | Carlsbad | CA | 23.78 | CAL107395 | Dec 2030 | Clarifiers, Biogas silos | 11 |
| 81 | Missouri River Wastewater Treatment Plant | Omaha | NE | 23.36 | NEL036358 | Dec 2030 | Clarifiers, Biogas balloons | 0 |
| 82 | City Of South Bend Wastewater Treatment Plant | South Bend | IN | 23.29 | IN0024520 | Nov 2026 | Clarifiers, Biogas silos, Biogas balloons | 4 |
| 83 | Ycua Regional Wastewater Treatment Plant | Ypsilanti | MI | 23.05 | MIL042676 | Dec 2030 | Clarifiers, Biogas silos | 5 |
| 84 | Anthony Ragnone Wastewater Treatment Plant | Montrose | MI | 23.04 | MI0022977 | Oct 2023 | Clarifiers, Uncovered lagoons, Biogas silos | 3 |
| 85 | City Of Garland Rowlett Creek WWTF | Garland | TX | 22.38 | TX0024686 | Oct 2030 | Clarifiers, Biogas silos | 6 |
| 86 | Ocean Cnty Util Auth Nwpcf | Bricktown | NJ | 22.16 | NJ0028142 | Mar 2026 | Clarifiers, Biogas silos, Biogas balloons | 0 |
| 87 | Southeast Water Reclamation Plant | Lubbock | TX | 21.96 | TX0106071 | Nov 2024 | Clarifiers, Biogas silos, Biogas balloons | 270 |
| 88 | Metropolitan Sewer Dis Little Miami WWTP | Cincinnati | OH | 21.87 | OH0025453 | Jun 2030 | Clarifiers, Biogas balloons | 8 |
| 89 | Waco Metropolitan Area Regional Sewarge System | Waco | TX | 21.83 | TX0026506 | Jul 2030 | Clarifiers, Uncovered lagoons, Biogas silos | 48 |
| 90 | Greater Lawrence Wastewater Treatment Facility | North Andover | MA | 21.7 | MAL100447 | Dec 2030 | Clarifiers, Biogas silos | 10 |
| 91 | Whites Creek Wastewater Treatment Plant | Nashville | TN | 21.51 | TN0024970 | Oct 2025 | Clarifiers, Aerated lagoons, Biogas balloons | 39 |
| 92 | Port Richmond Water Pollution Control Plant | Staten Island | NY | 21 | NY0026107 | Jun 2027 | Clarifiers, Biogas silos | 4 |
| 93 | Waste Water Treatment Plant | Youngstown | OH | 20.84 | OH0028223 | Oct 2028 | Biogas silos, Biogas balloons | 231 |
| 94 | Brushy Creek Regional Wastewater System - East | Round Rock | TX | 20.77 | TX0101940 | Jan 2029 | Clarifiers, Biogas balloons | 33 |
| 95 | Arlington County Water Pollution Control Plant | Arlington | VA | 20.7 | VA0025143 | Nov 2024 | Clarifiers, Biogas silos, Biogas balloons | 4 |
| 96 | Jefferson Parish Department Of Sewerage- East Bank WWTP | Elmwood | LA | 20.66 | LA0066630 | Jul 2028 | Clarifiers, Biogas silos | 0 |
| 97 | City Of Billings Wastewater Treatment Plant | Billings | MT | 20.31 | MTR000459 | Jan 2028 | Clarifiers, Uncovered lagoons, Biogas silos | 7 |
| 98 | New York (c) - Rockaway WPCP | Rockaway Park | NY | 20 | NY0026221 | Jun 2027 | Biogas silos | 3 |
| 99 | Piscataway Swge Plnt | Accokeek | MD | 19.79 | MDL021539 | Dec 2030 | Clarifiers, Biogas silos, Biogas balloons | 25 |
| 100 | Rahway Valley Sewerage Authority | Rahway | NJ | 19.3 | NJL024643 | Dec 2030 | Clarifiers, Biogas silos, Biogas balloons | 77 |
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.