How Clean Is Fall Lake?
Fall 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): 5.5 ft. Phosphorus: 21 µg/L. Chlorophyll-a (algae): 6 µg/L. Trophic State Index: 50.
Cleanliness Snapshot
| Metric | Fall Lake | Minnesota avg |
|---|---|---|
| Overall Grade | A | C |
| Water Clarity (Secchi) | 5.5 ft | — |
| Phosphorus | 21 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 6 µg/L | <10 = clean |
| Trophic State Index | 50 | <50 = clean |
How does Fall Lake compare?
Fall Lake's grade of A matches or beats the Minnesota state average of C. It ranks #6 of 35 lakes in Lake County by water quality score. Multi-year monitoring data shows water quality is declining based on 6 years of records.
Watch Fall Lake water quality
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