Is Rock Lake Safe for Swimming?
Rock Lake in Jefferson County, Wisconsin has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 12.5 ft visibility. Phosphorus: 17.9 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | A (Excellent) |
| Water Clarity (Secchi Depth) | 12.5 ft |
| Phosphorus | 17.9 μg/L |
| Location | Jefferson County, Wisconsin |
How does Rock Lake compare?
With an overall water quality grade of A, Rock Lake matches or beats the Wisconsin state average of Grade C. It ranks #1 of 8 lakes in Jefferson County by water quality score.
Water clarity (Secchi depth) sits at 12.5 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae.