Is Upper Cormorant Lake Polluted?
Yes — Upper Cormorant Lake in Becker County, Minnesota is on the EPA's Clean Water Act 303(d) impaired-waters list (2024 assessment cycle). It is cited for Impaired biota (cause unknown). No cleanup plan (TMDL) has been completed yet. "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) | Not yet written |
| Assessment cycle | 2024 |
| EPA IR category | 5 |
| Location | Becker County, Minnesota |
Pollutants Cited
- Impaired biota (cause unknown) — listed by EPA as exceeding water-quality standards for at least one designated use.
Specific parameters in the EPA record: FISH BIOASSESSMENTS.
What this means for using Upper Cormorant Lake
Review the EPA assessment and any state advisories before relying on Upper Cormorant Lake 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. Upper Cormorant Lake carries an overall water-quality grade of C and phosphorus at 30 µg/L — see the full breakdown on the lake report. The official EPA assessment is available in the ATTAINS waterbody report.