Is East Lake Osceola Polluted?
Yes — East Lake Osceola in Clarke County, Iowa is on the EPA's Clean Water Act 303(d) impaired-waters list (2024 assessment cycle). It is cited for Oxygen depletion (low DO), Turbidity. A formal cleanup plan — a Total Maximum Daily Load (TMDL) — has been written. "Impaired" is a legal designation, separate from the lake's A–F water-quality grade: it means at least one designated use (such as swimming, aquatic life, or fish consumption) does not meet state standards for the listed pollutant.
EPA 303(d) Listing
| On 303(d) impaired list | Yes |
| Cleanup plan (TMDL) | Completed |
| Assessment cycle | 2024 |
| EPA IR category | 5 |
| Location | Clarke County, Iowa |
Pollutants Cited
- Oxygen depletion (low DO) — listed by EPA as exceeding water-quality standards for at least one designated use.
- Turbidity — listed by EPA as exceeding water-quality standards for at least one designated use.
Specific parameters in the EPA record: DISSOLVED OXYGEN, TURBIDITY.
What this means for using East Lake Osceola
Review the EPA assessment and any state advisories before relying on East Lake Osceola for swimming, fishing, or other uses. An impairment listing does not mean the lake is closed — most impaired lakes remain open for boating and swimming. It means a specific pollutant exceeds a standard for a specific use. East Lake Osceola carries an overall water-quality grade of F, with algae (chlorophyll-a) at 81.6 µg/L — see the full breakdown on the lake report. The official EPA assessment is available in the ATTAINS waterbody report.