South Dakota wastewater permits expiring in 2026
26 NPDES permits · 0 MGD combined average flow
26 publicly owned wastewater treatment plants in South Dakota hold NPDES permits that expire during 2026, issued by South Dakota Department of Agriculture and 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) |
|---|---|---|---|---|---|---|
| Groton, City Of | Groton | — | SD0022187 | Mar 2026 | Uncovered lagoons | 8 |
| Menno, City Of | Menno | — | SD0020087 | Mar 2026 | Uncovered lagoons | 19 |
| Toronto, Town Of | Toronto | — | SD0021571 | Mar 2026 | Uncovered lagoons | 48 |
| Veblen, City Of | Veblen | — | SD0020001 | Mar 2026 | Uncovered lagoons | 76 |
| Armour, City Of | Armour | — | SD0020222 | Apr 2026 | Uncovered lagoons | 19 |
| Avon, City Of | Avon, City Of | — | SD0022730 | Apr 2026 | Uncovered lagoons | 120 |
| White River - City Of | White River | — | SD0022063 | Apr 2026 | Uncovered lagoons | 0 |
| Selby, City Of | Selby | — | SD0021717 | May 2026 | Uncovered lagoons | 84 |
| Eagle Butte WWTF | Eagle Butte | — | SD0020192 | Jun 2026 | Uncovered lagoons | 37 |
| Kimball, City Of | Kimball | — | SD0022772 | Jun 2026 | Uncovered lagoons | 14 |
| Leola, City Of | Leola | — | SD0022667 | Jun 2026 | Uncovered lagoons | 9 |
| Wessington Springs, City Of | Wessington Springs | — | SD0020460 | Jun 2026 | Uncovered lagoons | 33 |
| Iroquois, City Of | Iroquois | 0.14 | SDG922438 | Aug 2026 | Uncovered lagoons | 33 |
| Andover, Town Of | Andover | — | SDG921504 | Aug 2026 | Uncovered lagoons | 112 |
| Bonesteel- City Of | Bonesteel | — | SDG920842 | Aug 2026 | Uncovered lagoons | 2 |
| Cavour, Town Of | Cavour | — | SDG921806 | Aug 2026 | Uncovered lagoons | 2 |
| Hitchcock, Town Of | Hitchcock | — | SDG926051 | Aug 2026 | Uncovered lagoons | 1 |
| Hurley - City Of | Hurley | — | SDG821997 | Aug 2026 | Aerated lagoons, Uncovered lagoons | — |
| Labolt, Town Of | Labolt | — | SDG926662 | Aug 2026 | Uncovered lagoons | 114 |
| Langford, Town Of | Langford | — | SDG922705 | Aug 2026 | Uncovered lagoons | 21 |
| Mellette , City Of | Mellette | — | SDG920672 | Aug 2026 | Uncovered lagoons | 4 |
| Murdo, City Of | Murdo | — | SDG920818 | Aug 2026 | Aerated lagoons, Uncovered lagoons | 16 |
| Reliance - Town Of | Reliance | — | SDG920231 | Aug 2026 | Aerated lagoons, Uncovered lagoons | 64 |
| Stickney, Town Of | Stickney | — | SDG921491 | Aug 2026 | Uncovered lagoons | 0 |
| Tea, City Of | Tea, City Of | — | SDG921784 | Aug 2026 | Aerated lagoons, Uncovered lagoons | 3 |
| Tyndall, City Of | Tyndall | — | SDG920133 | Aug 2026 | Uncovered lagoons | 0 |
South Dakota permit renewals in 2026: 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.