Iowa wastewater permits expiring in 2027
95 NPDES permits · 0 MGD combined average flow
95 publicly owned wastewater treatment plants in Iowa hold NPDES permits that expire during 2027, issued by Iowa Department of Natural Resources. The table lists each plant with its permit number, expiry month, average flow, treatment technology and three-year violation count, in order of expiry.
An NPDES permit runs for five years. To keep discharging, a plant must apply for renewal at least 180 days before the expiry date, and the renewed permit usually arrives with tighter effluent limits, new monitoring requirements or a compliance schedule. That is why the year a permit expires is the year a plant starts budgeting for upgrades: nutrient removal, disinfection, capacity or controls.
| Facility | City | Avg flow (MGD) | NPDES permit | Expires | Technology | Violations (3y) |
|---|---|---|---|---|---|---|
| Bayard WWTP | Bayard | — | IA0061468 | Jan 2027 | Uncovered lagoons | 127 |
| Bedford City Of STP | Bedford | — | IA0026018 | Jan 2027 | Uncovered lagoons | 3 |
| Burlington, City Of (wwtp) | Burlington | — | IA0043079 | Jan 2027 | Clarifiers, Biogas silos | 4 |
| City Of Shenandoah STP | Shenandoah | — | IA0032328 | Jan 2027 | Clarifiers, Aerated lagoons, Biogas silos, Biogas balloons | 75 |
| Kellerton City Of STP | Kellerton | — | IA0061760 | Jan 2027 | Uncovered lagoons | 1 |
| Riverton WWTP | Riverton | — | IA0077097 | Jan 2027 | Uncovered lagoons | 0 |
| Shell Rock WWTP | Shell Rock | — | IA0033359 | Jan 2027 | Aerated lagoons, Uncovered lagoons | 48 |
| Whiting City Of STP | Whiting | — | IA0032719 | Jan 2027 | Uncovered lagoons | 0 |
| Central City City Of STP | Central City | — | IA0027979 | Feb 2027 | Aerated lagoons, Uncovered lagoons | 6 |
| Cleghorn WWTP | Cleghorn | — | IA0042846 | Feb 2027 | Uncovered lagoons | 0 |
| Dakota City City Of STP | Dakota City | — | IA0048003 | Feb 2027 | Uncovered lagoons | 0 |
| Huxley City Of STP | Huxley | — | IA0083518 | Feb 2027 | Clarifiers, Carrousels / oxidation ditches | 2 |
| Lawler City Of STP | Lawler | — | IA0056910 | Feb 2027 | Uncovered lagoons | 0 |
| Marquette WWTP | Marquette | — | IA0059463 | Feb 2027 | Uncovered lagoons | 1 |
| Massena WWTP | Massena | — | IA0048348 | Feb 2027 | Uncovered lagoons | 29 |
| Olin WWTP | Olin | — | IA0036064 | Feb 2027 | Uncovered lagoons | 9 |
| Rose Hill City Of STP | Rose Hill | — | IA0072311 | Feb 2027 | Uncovered lagoons | 12 |
| Schaller City Of STP | Schaller | — | IA0042935 | Feb 2027 | Uncovered lagoons | 13 |
| City Of Pella | Pella | — | IA0043869 | Mar 2027 | Clarifiers, Biogas silos, Biogas balloons | 0 |
| Clarinda City Of STP | Clarinda | — | IA0035190 | Mar 2027 | Aerated lagoons, Uncovered lagoons | 17 |
| Delhi City Of STP | Delhi | — | IA0047848 | Mar 2027 | Uncovered lagoons | 6 |
| Eddyville, City Of STP | Eddyville | — | IA0020770 | Mar 2027 | Aerated lagoons, Uncovered lagoons | 14 |
| Elgin WWTP | Elgin | — | IA0024414 | Mar 2027 | Uncovered lagoons | 0 |
| Elkader WWTP | Elkader | — | IA0021962 | Mar 2027 | Aerated lagoons, Uncovered lagoons | 0 |
| Fonda City Of STP | Fonda | — | IA0046671 | Mar 2027 | Uncovered lagoons | 0 |
| Griswold WWTP | Griswold | — | IA0031411 | Mar 2027 | Uncovered lagoons | 4 |
| Luana City Of STP | Luana | — | IA0027685 | Mar 2027 | Uncovered lagoons | 0 |
| Paullina WWTF | Paullina | — | IA0032352 | Mar 2027 | Uncovered lagoons | 2 |
| Princeton City Of STP | Princeton | — | IA0033227 | Mar 2027 | Aerated lagoons | 20 |
| Sutherland Stl | Sutherland | — | IA0036129 | Mar 2027 | Uncovered lagoons | 15 |
| Thayer City Of STP | Thayer | — | IA0079936 | Mar 2027 | Uncovered lagoons | 0 |
| Ainsworth City Of STP | Ainsworth | — | IA0069183 | Apr 2027 | Uncovered lagoons | 13 |
| Baxter WWTP | Baxter | — | IA0023353 | Apr 2027 | Uncovered lagoons | 15 |
| Bloomfield WWTP (main) | Bloomfield | — | IA0047929 | Apr 2027 | Aerated lagoons | 8 |
| Dayton City Of STP | Dayton | — | IA0023558 | Apr 2027 | Uncovered lagoons | 4 |
| Grand Junction WWTP | Grand Junction | — | IA0041891 | Apr 2027 | Uncovered lagoons | 0 |
| Kalona City Of STP | Kalona | — | IA0059196 | Apr 2027 | Uncovered lagoons | 57 |
| Kirkville, City Of | Ottumwa | — | IA0074667 | Apr 2027 | Uncovered lagoons | 4 |
| New Vienna WWTP | New Vienna | — | IA0027391 | Apr 2027 | Aerated lagoons | 58 |
| Prescott City Of STP | Prescott | — | IA0033456 | Apr 2027 | Uncovered lagoons | 6 |
| Runnells City Of STP | Runnells | — | IA0063355 | Apr 2027 | Clarifiers, Covered lagoons | 84 |
| Armstrong City Of STP | Armstrong | — | IA0028517 | May 2027 | Aerated lagoons, Uncovered lagoons | 107 |
| Glidden WWTP | Glidden | — | IA0024571 | May 2027 | Aerated lagoons, Uncovered lagoons | 18 |
| Irwin City Of STP | Irwin | — | IA0021024 | May 2027 | Uncovered lagoons | 0 |
| Lake Mills City Of STP | Lake Mills | — | IA0027448 | May 2027 | Aerated lagoons | 70 |
| Lamoni WWTP | Lamoni | — | IA0036102 | May 2027 | Uncovered lagoons | 6 |
| Macedonia City Of STP | Macedonia | — | IA0042919 | May 2027 | Uncovered lagoons | 0 |
| Redfield WWTP | Redfield | — | IA0036099 | May 2027 | Uncovered lagoons | 7 |
| Silver City, City Of STP | Silver City | — | IA0079774 | May 2027 | Uncovered lagoons | 0 |
| Afton City Of STP | Afton | — | IA0041831 | Jun 2027 | Uncovered lagoons | 0 |
| Anita City Of STP | Anita | — | IA0024520 | Jun 2027 | Aerated lagoons | 1 |
| East Peru City Of STP (warren Water District) | Peru | — | IA0079791 | Jun 2027 | Uncovered lagoons | 1 |
| Nichols City Of STP | Nichols | — | IA0036561 | Jun 2027 | Uncovered lagoons | 1 |
| Bonaparte City Of STP | Bonaparte | — | IA0050628 | Jul 2027 | Uncovered lagoons | 3 |
| Corning City Of STP | Corning | — | IA0027375 | Jul 2027 | Uncovered lagoons | 13 |
| Harpers Ferry, City Of STP | Harpers Ferry | — | IA0070564 | Jul 2027 | Aerated lagoons | 0 |
| Keswick, City Of STP | Keswick | — | IA0079910 | Jul 2027 | Uncovered lagoons | 5 |
| Oto City Of STP | Oto | — | IA0065811 | Jul 2027 | Uncovered lagoons | 0 |
| Patterson City Of STP | Patterson | — | IA0062961 | Jul 2027 | Uncovered lagoons | 0 |
| Richland WWTP | Richland | — | IA0061328 | Jul 2027 | Uncovered lagoons | 0 |
| Walker City Of STP | Walker | — | IA0059081 | Jul 2027 | Aerated lagoons, Uncovered lagoons | 3 |
| Wayland, City Of STP | Wayland | — | IA0047953 | Jul 2027 | Aerated lagoons, Uncovered lagoons | 30 |
| Carroll WWTP | Carroll | — | IA0021377 | Aug 2027 | Clarifiers, Uncovered lagoons, Biogas silos, Biogas balloons | 1 |
| Coin City Of STP | Coin | — | IA0062332 | Aug 2027 | Uncovered lagoons | 0 |
| Farmington City Of STP | Farmington | — | IA0060313 | Aug 2027 | Aerated lagoons, Uncovered lagoons | 16 |
| Hinton City Of STP | Hinton | — | IA0057053 | Aug 2027 | Uncovered lagoons | 7 |
| Indianola Water Resource Recovery Facility | Indianola | — | IA0053405 | Aug 2027 | Clarifiers, Carrousels / oxidation ditches | 5 |
| Paton WWTP | Paton | — | IA0060321 | Aug 2027 | Uncovered lagoons | 0 |
| Pleasantville Water Works | Pleasantville | — | IA0035921 | Aug 2027 | Uncovered lagoons | 9 |
| Rembrandt WWTP | Rembrandt | — | IA0033219 | Aug 2027 | Uncovered lagoons | 0 |
| Van Meter City Of STP | Van Meter | — | IA0036021 | Aug 2027 | Uncovered lagoons | 9 |
| Anthon City Of STP | Anthon | — | IA0042854 | Sep 2027 | Uncovered lagoons | 0 |
| Conesville City Of STP | Conesville | — | IA0058769 | Sep 2027 | Uncovered lagoons | 6 |
| Essex City Of STP | Essex | — | IA0026603 | Sep 2027 | Uncovered lagoons | 42 |
| Homestead Sanitary District | Homestead | — | IA0023591 | Sep 2027 | Aerated lagoons, Uncovered lagoons | 3 |
| Lost Nation City Of STP | Lost Nation | — | IA0036544 | Sep 2027 | Uncovered lagoons | 0 |
| Melcher-Dallas WWTP | Melcher-Dallas | — | IA0047783 | Sep 2027 | Uncovered lagoons | 2 |
| Rockford WWTP | Rockford | — | IA0058432 | Sep 2027 | Uncovered lagoons | 1 |
| Rowley City Of STP | Rowley | — | IA0043672 | Sep 2027 | Uncovered lagoons | 5 |
| Sidney WWTP | Sidney | — | IA0035971 | Sep 2027 | Uncovered lagoons | 0 |
| Decorah City Of STP | Decorah | — | IA0035220 | Oct 2027 | Clarifiers, Biogas silos | 3 |
| George City Of STP | George | — | IA0036081 | Oct 2027 | Uncovered lagoons | 21 |
| Marshalltown City Of STP | Marshalltown | — | IA0038610 | Oct 2027 | Uncovered lagoons, Biogas silos, Biogas balloons | 8 |
| Rockwell WWTP | Rockwell | — | IA0033481 | Oct 2027 | Uncovered lagoons | 0 |
| Sherrill East WWTP | Sherrill | — | IA0056952 | Oct 2027 | Uncovered lagoons | 0 |
| Adel WWTP | Adel | — | IA0041921 | Nov 2027 | Uncovered lagoons | 2 |
| Doon City Of STP | Doon | — | IA0023736 | Nov 2027 | Uncovered lagoons | 36 |
| Dundee City Of STP | Dundee | — | IA0062839 | Nov 2027 | Uncovered lagoons | 4 |
| Ellsworth WWTP | Ellsworth | — | IA0026280 | Nov 2027 | Uncovered lagoons | 0 |
| Gilman City Of STP | Gilman | — | IA0029033 | Nov 2027 | Aerated lagoons, Uncovered lagoons | 4 |
| Graettinger City Of STP | Graettinger | — | IA0027821 | Nov 2027 | Uncovered lagoons | 2 |
| West Branch City Of STP | West Branch | — | IA0032859 | Nov 2027 | Aerated lagoons | 19 |
| Humeston City Of STP | Humeston | — | IA0043150 | Dec 2027 | Aerated lagoons | 29 |
| Monticello WWTP | Monticello | — | IA0026034 | Dec 2027 | Clarifiers, Uncovered lagoons, Biogas silos, Biogas balloons | 7 |
| Sumner City Of STP | Sumner | — | IA0033766 | Dec 2027 | Carrousels / oxidation ditches, Biogas silos | 1 |
Iowa permit renewals in 2027: 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.