Oxidation ditches: wastewater treatment plants in Kansas
33 plants · 9% of the state · 45 MGD reported by 32 plants
Klarifi identifies 33 publicly owned wastewater treatment plants with oxidation ditches in Kansas, 9% of the 355 plants in the state (45 MGD reported by 32 plants). The largest is Topeka Oakland Wastewater Plant in Topeka at 11.13 MGD.
Oxidation ditches are ring-shaped activated sludge reactors with long retention times, common at plants between 0.5 and 10 MGD. They are recognisable from the air by their looped channels and rely on surface aerators or brush rotors, which are frequent replacement and energy-efficiency projects.
The largest oxidation ditch plants in Kansas
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | Topeka Oakland Wastewater Plant | Topeka | 11.13 | KS0042722 | Jan 2027 | 64 |
| 2 | Olathe (cedar Creek) Wastewater Plant | Olathe | 4.47 | KS0081299 | Dec 2029 | 0 |
| 3 | Hutchinson, City Of | Hutchinson | 3.3 | KS0036188 | Dec 2028 | 17 |
| 4 | Garden City, City Of | Garden City | 2.56 | KS0038962 | Dec 2026 | 3 |
| 5 | Wichita - Four Mile Creek - New | Wichita | 2.38 | KS0100790 | Dec 2026 | 9 |
| 6 | Fort Scott, City Of (new Plant) | Fort Scott | 2.33 | KS0095923 | Oct 2028 | 35 |
| 7 | Gardner - Kill Creek | Gardner | 2.06 | KS0095605 | Oct 2026 | 79 |
| 8 | Derby Wastewater Treatment | Derby | 2.03 | KS0050377 | Dec 2027 | 61 |
| 9 | Lawrence, City Of (wakarusa) | Lawrence | 1.97 | KS0099031 | Aug 2029 | 0 |
| 10 | Hays, City Of - Chetolah Creek Water Re | Hays | 1.33 | KS0100820 | Dec 2030 | 0 |
Contacts and project signals for every plant on this list
Klarifi adds verified decision-maker contacts, permit limits, discharge monitoring data and the capital projects planned in each city, filterable by technology, size and compliance record.
Other technologies in Kansas
Oxidation ditches in other states
Oxidation ditches in Kansas: 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: Oxidation ditch · Activated sludge · Biological nutrient removal · Lift station · Inflow and infiltration · all terms