Is Long Lake Safe for Swimming?
Long Lake in Fond du Lac County, Wisconsin has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 32.8 ft visibility. Phosphorus: 19.3 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | A (Excellent) |
| Water Clarity (Secchi Depth) | 32.8 ft |
| Phosphorus | 19.3 μg/L |
| Maximum Depth | 47 ft |
| Location | Fond du Lac County, Wisconsin |
How does Long Lake compare?
With an overall water quality grade of A, Long Lake matches or beats the Wisconsin state average of Grade B. It ranks #1 of 10 lakes in Fond du Lac County by water quality score.
Water clarity (Secchi depth) sits at 32.8 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae.