How Clean Is Delavan Lake?
Delavan Lake is a clean lake by Wisconsin standards. It received a water quality grade of B (Good) based on EPA monitoring data. Water clarity (Secchi depth): 9.1 ft. Phosphorus: 27 µg/L. Trophic State Index: 48.
Cleanliness Snapshot
| Metric | Delavan Lake | Wisconsin avg |
|---|---|---|
| Overall Grade | B | C |
| Water Clarity (Secchi) | 9.1 ft | — |
| Phosphorus | 27 µg/L | <30 = clean |
| Trophic State Index | 48 | <50 = clean |
How does Delavan Lake compare?
Delavan Lake's grade of B matches or beats the Wisconsin state average of C. It ranks #16 of 34 lakes in Walworth County by water quality score. Multi-year monitoring data shows water quality is declining based on 6 years of records.