Is Rock Lake Safe for Swimming?
Rock Lake in Jefferson County, Wisconsin has a water quality grade of B (Good). Good for swimming, clear water with low algae levels. Water clarity: 12 ft visibility. Phosphorus: 18.1 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | B (Good) |
| Water Clarity (Secchi Depth) | 12 ft |
| Phosphorus | 18.1 μg/L |
| Maximum Depth | 60 ft |
| Location | Jefferson County, Wisconsin |
How does Rock Lake compare?
With an overall water quality grade of B, Rock Lake matches or beats the Wisconsin state average of Grade B. It ranks #1 of 7 lakes in Jefferson County by water quality score.
Water clarity (Secchi depth) sits at 12 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae.
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