Is Roy Lake Safe for Swimming?
Roy Lake in Mahnomen County, Minnesota has nutrient and algae measurements on record from state and federal monitoring. A water-quality reading is not a swimming clearance. The state water agency and county health departments post current advisories; check them before you swim.. Water clarity: 6 ft visibility. Phosphorus: 24 µg/L. Chlorophyll-a (algae): 13.6 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Water Clarity (Secchi Depth) | 6 ft |
| Phosphorus | 24 μg/L |
| Chlorophyll-a (Algae) | 13.6 μg/L |
| Maximum Depth | 16 ft |
| Location | Mahnomen County, Minnesota |
How does Roy Lake compare?
With an overall water-quality readings of —, Roy Lake matches or beats the Minnesota state average. It ranks #7 of 12 lakes in Mahnomen County by water quality score.
Water clarity (Secchi depth) sits at 6 feet. That puts the lake in good clarity range, with limited algae interference. Algae levels (chlorophyll-a) measure 13.6 µg/L — moderate; acceptable for swimming on most days, but worth checking advisories.
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