How Clean Is Green Lake?
Green Lake is among the cleanest lakes in Wisconsin. Its nutrient and algae readings come from EPA monitoring data. Water clarity (Secchi depth): 13.5 ft. Phosphorus: 38.1 µg/L. Chlorophyll-a (algae): 4.4 µg/L. Trophic State Index: 47.
Cleanliness Snapshot
| Metric | Green Lake | Wisconsin avg |
|---|---|---|
| Water Clarity (Secchi) | 13.5 ft | — |
| Phosphorus | 38.1 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 4.4 µg/L | <10 = clean |
| Trophic State Index | 47 | <50 = clean |
How does Green Lake compare?
Green Lake's readings match or beat the Wisconsin state average. It ranks #1 of 7 lakes in Green Lake County by water quality score. Multi-year monitoring data shows water quality is improving based on 3 years of records.
Watch Green Lake water quality
Get an email when the clarity or algae readings change. Unsubscribe anytime.