Is Upper Hay Lake Safe for Swimming?
Upper Hay Lake in Crow Wing County, Minnesota has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 10.9 ft visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 4.8 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | A (Excellent) |
| Water Clarity (Secchi Depth) | 10.9 ft |
| Phosphorus | 20 μg/L |
| Chlorophyll-a (Algae) | 4.8 μg/L |
| Maximum Depth | 42 ft |
| Location | Crow Wing County, Minnesota |
How does Upper Hay Lake compare?
With an overall water quality grade of A, Upper Hay Lake matches or beats the Minnesota state average of Grade C. It ranks #47 of 85 lakes in Crow Wing County by water quality score.
Water clarity (Secchi depth) sits at 10.9 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae. Algae levels (chlorophyll-a) measure 4.8 µg/L — low and well within safe swimming guidelines.