How Clean Is Birch Lake?
Birch 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): 13.7 ft. Phosphorus: 12 µg/L. Trophic State Index: 40.
Cleanliness Snapshot
| Metric | Birch Lake | Minnesota avg |
|---|---|---|
| Overall Grade | A | C |
| Water Clarity (Secchi) | 13.7 ft | — |
| Phosphorus | 12 µg/L | <30 = clean |
| Trophic State Index | 40 | <50 = clean |
How does Birch Lake compare?
Birch Lake's grade of A matches or beats the Minnesota state average of C. It ranks #51 of 133 lakes in Cass County by water quality score. Multi-year monitoring data shows water quality is declining based on 5 years of records.