Is Upper South Long Lake Safe for Swimming?
Upper South Long Lake in Crow Wing 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: 16 µg/L. Chlorophyll-a (algae): 8.5 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Water Clarity (Secchi Depth) | 6 ft |
| Phosphorus | 16 μg/L |
| Chlorophyll-a (Algae) | 8.5 μg/L |
| Maximum Depth | 47 ft |
| Location | Crow Wing County, Minnesota |
How does Upper South Long Lake compare?
With an overall water-quality readings of —, Upper South Long Lake matches or beats the Minnesota state average. It ranks #68 of 85 lakes in Crow Wing 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 8.5 µg/L — moderate; acceptable for swimming on most days, but worth checking advisories.
Watch Upper South Long Lake water quality
Get an email when the clarity or algae readings change. Unsubscribe anytime.