How Clean Is Chisago Lake?
Chisago Lake has poor water quality, with elevated phosphorus and algae. It received a water quality grade of D (Poor) based on EPA monitoring data. Water clarity (Secchi depth): 4 ft. Phosphorus: 25.5 µg/L. Chlorophyll-a (algae): 14.9 µg/L. Trophic State Index: 55.
Cleanliness Snapshot
| Metric | Chisago Lake | Minnesota avg |
|---|---|---|
| Overall Grade | D | C |
| Water Clarity (Secchi) | 4 ft | — |
| Phosphorus | 25.5 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 14.9 µg/L | <10 = clean |
| Trophic State Index | 55 | <50 = clean |
How does Chisago Lake compare?
Chisago Lake's grade of D falls below the Minnesota state average of C. It ranks #19 of 30 lakes in Chisago County by water quality score. Multi-year monitoring data shows water quality is improving based on 6 years of records.