How Clean Is Jonathan Lake?
Jonathan Lake has very poor water quality and a high algae bloom risk. It received a water quality grade of F (Very Poor) based on EPA monitoring data. Water clarity (Secchi depth): 1.5 ft. Phosphorus: 157.5 µg/L. Trophic State Index: 74.
Cleanliness Snapshot
| Metric | Jonathan Lake | Minnesota avg |
|---|---|---|
| Overall Grade | F | C |
| Water Clarity (Secchi) | 1.5 ft | — |
| Phosphorus | 157.5 µg/L | <30 = clean |
| Trophic State Index | 74 | <50 = clean |
How does Jonathan Lake compare?
Jonathan Lake's grade of F falls below the Minnesota state average of C. It ranks #26 of 40 lakes in Carver County by water quality score. Multi-year monitoring data shows water quality is stable based on 5 years of records.