Is Sylvan Lake Safe for Swimming?
Sylvan Lake in Cass County, Minnesota has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 19.5 ft visibility. Phosphorus: 7 µg/L. Chlorophyll-a (algae): 2.1 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | A (Excellent) |
| Water Clarity (Secchi Depth) | 19.5 ft |
| Phosphorus | 7 μg/L |
| Chlorophyll-a (Algae) | 2.1 μg/L |
| Location | Cass County, Minnesota |
How does Sylvan Lake compare?
With an overall water quality grade of A, Sylvan Lake matches or beats the Minnesota state average of Grade C. It ranks #46 of 104 lakes in Cass County by water quality score.
Water clarity (Secchi depth) sits at 19.5 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae. Algae levels (chlorophyll-a) measure 2.1 µg/L — low and well within safe swimming guidelines.
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