The 50 largest wastewater treatment plants in Missouri
Ranked by average flow · 525 MGD combined · 81% of the state's reported flow
Metropolitan St. Louis Sewer District Bissell Point WWTP in St. Louis is the largest publicly owned wastewater treatment plant in Missouri by reported average flow, treating about 123.06 million gallons per day. The 50 plants below treat 525 MGD between them, 81% of the flow reported by all 671 plants in the state, and serve about 2,847,233 people. Every plant links to its profile with permit and compliance data. Treatment technology is shown with a free Klarifi account.
| # | Facility | City | Avg flow (MGD) | Population | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|---|
| 1 | Metropolitan St. Louis Sewer District Bissell Point WWTP | St. Louis | 123.06 | 304,678 | MO0025178 | Aug 2031 | 14 |
| 2 | Metropolitan St. Louis Sewer District Lemay WWTP | St. Louis | 105.45 | 453,428 | MO0025151 | Aug 2031 | 6 |
| 3 | Little Blue Valley Sewer District | Independence | 39.13 | 39,046 | MOL101087 | Dec 2030 | 14 |
| 4 | Southwest WWTP | Springfield | 30.9 | 206,375 | MO0049522 | Jul 2025 | 0 |
| 5 | MSD Coldwater WWTP | Florissant | 22.75 | 160,833 | MO0025160 | Aug 2031 | 1 |
| 6 | St. Joseph Water Protection Facility | Saint Joseph | 20.69 | 77,300 | MO0023043 | Nov 2025 | 4 |
| 7 | Kc, Westside WWTP | Kansas City | 14.89 | 227,510 | MO0024929 | Jun 2026 | 2 |
| 8 | Metropolitan St Louis Sewer District-Grand Glaize Wastewater Treatment Plant | Valley Park | 12.6 | 113,693 | MO0101362 | Aug 2031 | 0 |
| 9 | MSD Lower Meramec WWTP | St. Louis | 9.68 | 68,482 | MO0127949 | Aug 2031 | 0 |
| 10 | Joplin Turkey Creek WWTP | Joplin | 9.49 | 53,845 | MO0103349 | Sep 2022 | 65 |
| 11 | O' Fallon Wastewater Treatment Plant | O'Fallon | 7.55 | 88,132 | MO0028720 | Sep 2031 | 0 |
| 12 | Jefferson City Rwrf | Jefferson City | 7.03 | 43,841 | MO0094846 | Mar 2025 | 0 |
| 13 | Rock Creek Waste Treatment | Independence | 6.35 | 113,681 | MO0089681 | Mar 2024 | 12 |
| 14 | Shoal Creek Wastewater Treatment Facility | Joplin | 5.66 | 34,800 | MO0023256 | Mar 2023 | 11 |
| 15 | St Peters Pws | Saint Peters | 5.65 | 57,536 | MO0030970 | Dec 2024 | 0 |
| 16 | Cape Girardeau WWTP | Cape Girardeau | 5.39 | 40,100 | MO0136328 | Jun 2024 | 0 |
| 17 | Springfield NW WWTP | Springfield | 5 | 6,344 | MO0103039 | Jul 2025 | 0 |
| 18 | Dcsd Wastewater Treatment Plant 2 | Weldon Spring | 4.93 | 5,536 | MO0116572 | Dec 2025 | 0 |
| 19 | Blue Springs, Sni A Bar WWTF | Grain Valley | 4.89 | 42,549 | MO0028886 | Nov 2028 | 16 |
| 20 | Poplar Bluff Municipal WWTP | Poplar Bluff | 4.75 | 16,979 | MO0043648 | Sep 2024 | 4 |
| 21 | Wentzville Pws | Wentzville | 4.64 | 41,342 | MO0093599 | Mar 2024 | 4 |
| 22 | Duckett Creek Sanitation District Treatment Plant #1 | Saint Charles | 4.45 | 5,439 | MO0085472 | Jun 2021 | 0 |
| 23 | Carthage WWTP | Carthage | 4.22 | 74,700 | MO0039136 | Mar 2023 | 4 |
| 24 | St Charles Missouri River WWTP | St. Charles | 4.2 | 70,650 | MO0058351 | Sep 2025 | 0 |
| 25 | MSD Fenton Waste Water Treatment Plant | Fenton | 4.04 | 21,144 | MO0086126 | Dec 2022 | 0 |
| 26 | Hannibal Pws | Hannibal | 3.71 | 17,312 | MO0093513 | Apr 2023 | 2 |
| 27 | Rolla Pws-Well 4 - E 10th St | Rolla | 3.4 | 47,650 | MO0050652 | Jun 2023 | 0 |
| 28 | Center Creek WWTP | Webb City | 2.78 | 11,884 | MO0040185 | Apr 2030 | 149 |
| 29 | Monett Wastewater Treatment Plant | Monett | 2.77 | 75,312 | MO0021440 | Jun 2029 | 17 |
| 30 | Lebanon WWTP | Lebanon | 2.75 | 14,735 | MO0089010 | Sep 2031 | 3 |
| 31 | Marshall SE WWTP | Marshall | 2.73 | 12,920 | MO0032883 | Mar 2022 | 0 |
| 32 | Kirksville WWTP | Kirksville | 2.71 | 17,645 | MO0049506 | Dec 2027 | 0 |
| 33 | Washington WWTP | Washington | 2.48 | 4,684 | MO0025810 | Mar 2026 | 2 |
| 34 | Sedalia Southeast WWTP | Sedalia | 2.48 | 21,634 | MO0101567 | Oct 2028 | 59 |
| 35 | Bismarck Pws | Bismarck | 2.33 | 1,731 | MO0022942 | Mar 2031 | 6 |
| 36 | Branson Compton Drive WWTP | Branson | 2.33 | 59,086 | MO0025241 | Sep 2024 | 1 |
| 37 | Waynesville Pws | Waynesville | 2.26 | 1,753 | MO0094161 | Jun 2025 | 2 |
| 38 | Sikeston WWTP | Sikeston | 2.25 | 30,000 | MO0035009 | Sep 2025 | 0 |
| 39 | Pleasant Hill Pws | Pleasant Hill | 2.13 | 21,568 | MO0058629 | Mar 2026 | 0 |
| 40 | Moberly WWTP | Moberly | 2.08 | 13,974 | MO0117960 | Oct 2024 | 6 |
| 41 | Festus-Crystal City WWTP | Crystal City | 2 | 7,500 | MO0080632 | Sep 2021 | 14 |
| 42 | Neosho WWTP | Neosho | 1.89 | 29,000 | MO0104906 | Apr 2022 | 30 |
| 43 | Sedalia Central WWTP | Sedalia | 1.88 | 30,300 | MO0023019 | Oct 2028 | 52 |
| 44 | Hollister WWTF | Hollister | 1.85 | 3,000 | MO0116041 | Dec 2024 | 2 |
| 45 | Vandalia WWTF | Vandalia | 1.84 | 3,903 | MO0026361 | Dec 2025 | 24 |
| 46 | Fulton WWTP | Fulton | 1.8 | 12,696 | MO0103331 | Nov 2028 | 26 |
| 47 | Kimmswick WWTP | Imperial | 1.79 | 16,000 | MO0106461 | Aug 2028 | 2 |
| 48 | Perryville SE WWTP | Perryville | 1.77 | 8,440 | MO0051144 | Jun 2029 | 3 |
| 49 | Farmington East WWTP | Farmington | 1.71 | 15,625 | MO0028860 | Sep 2021 | 39 |
| 50 | Park Hills Mineral Belt WWTP | Bonne Terre | 1.71 | 918 | MO0103560 | May 2022 | 1 |
Treatment technology for each plant is shown with a free Klarifi account. Create one →
Largest plants in Missouri: 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: WWTP · POTW · MGD · NPDES permit · Significant industrial user · Biosolids · all terms
Cite this page
Journalists, researchers and educators are welcome to quote these figures. Please credit Klarifi as the source and link to this page.
Klarifi. “Largest wastewater treatment plants in Missouri (2026).” Updated October 26, 2026. https://klarifi.io/facilities/missouri/largestNeed a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.