How Clean Is Mule Lake?
Mule Lake is among the cleanest lakes in Minnesota. It received a water quality grade of A (Excellent) based on EPA monitoring data. Water clarity (Secchi depth): 18.7 ft. Phosphorus: 9 µg/L. Trophic State Index: 35.
Cleanliness Snapshot
| Metric | Mule Lake | Minnesota avg |
|---|---|---|
| Overall Grade | A | C |
| Water Clarity (Secchi) | 18.7 ft | — |
| Phosphorus | 9 µg/L | <30 = clean |
| Trophic State Index | 35 | <50 = clean |
How does Mule Lake compare?
Mule Lake's grade of A matches or beats the Minnesota state average of C. It ranks #29 of 133 lakes in Cass County by water quality score. Multi-year monitoring data shows water quality is improving based on 5 years of records.