How Clean Is Lake Poygan?
Lake Poygan has fair water quality — typical of lakes with moderate nutrient enrichment. It received a water quality grade of C (Fair) based on EPA monitoring data. Water clarity (Secchi depth): 8.2 ft. Trophic State Index: 47.
Cleanliness Snapshot
| Metric | Lake Poygan | Wisconsin avg |
|---|---|---|
| Overall Grade | C | B |
| Water Clarity (Secchi) | 8.2 ft | — |
| Trophic State Index | 47 | <50 = clean |
How does Lake Poygan compare?
Lake Poygan's grade of C falls below the Wisconsin state average of B. It ranks #4 of 5 lakes in Winnebago County by water quality score. Multi-year monitoring data shows water quality is stable based on 6 years of records.