How Clean Is Greenwood Lake?
Greenwood 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): 15.1 ft. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 2.6 µg/L. Trophic State Index: 38.
Cleanliness Snapshot
| Metric | Greenwood Lake | Minnesota avg |
|---|---|---|
| Overall Grade | A | C |
| Water Clarity (Secchi) | 15.1 ft | — |
| Phosphorus | 10 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 2.6 µg/L | <10 = clean |
| Trophic State Index | 38 | <50 = clean |
How does Greenwood Lake compare?
Greenwood Lake's grade of A matches or beats the Minnesota state average of C. It ranks #29 of 44 lakes in Cook County by water quality score. Multi-year monitoring data shows water quality is improving based on 4 years of records.