How Clean Is Big Round Lake?
Big Round Lake 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): 5.6 ft. Phosphorus: 27.6 µg/L. Chlorophyll-a (algae): 21 µg/L. Trophic State Index: 55.
Cleanliness Snapshot
| Metric | Big Round Lake | Wisconsin avg |
|---|---|---|
| Overall Grade | C | B |
| Water Clarity (Secchi) | 5.6 ft | — |
| Phosphorus | 27.6 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 21 µg/L | <10 = clean |
| Trophic State Index | 55 | <50 = clean |
How does Big Round Lake compare?
Big Round Lake's grade of C falls below the Wisconsin state average of B. It ranks #68 of 77 lakes in Polk County by water quality score. Multi-year monitoring data shows water quality is improving based on 7 years of records.