How Clean Is Lac Courte Oreilles Lake?
Lac Courte Oreilles Lake is among the cleanest lakes in Wisconsin. It received a water quality grade of A (Excellent) based on EPA monitoring data. Water clarity (Secchi depth): 12.2 ft. Phosphorus: 16 µg/L. Chlorophyll-a (algae): 1.4 µg/L. Trophic State Index: 40.
Cleanliness Snapshot
| Metric | Lac Courte Oreilles Lake | Wisconsin avg |
|---|---|---|
| Overall Grade | A | C |
| Water Clarity (Secchi) | 12.2 ft | — |
| Phosphorus | 16 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 1.4 µg/L | <10 = clean |
| Trophic State Index | 40 | <50 = clean |
How does Lac Courte Oreilles Lake compare?
Lac Courte Oreilles Lake's grade of A matches or beats the Wisconsin state average of C. It ranks #8 of 50 lakes in Sawyer County by water quality score. Multi-year monitoring data shows water quality is improving based on 5 years of records.