Is Hall Lake Safe for Swimming?
Hall Lake in Martin County, Minnesota has a water quality grade of F (Very Poor). Avoid swimming, very poor water quality, potential algae toxins. Water clarity: 2.6 ft visibility. Phosphorus: 96 µg/L. Chlorophyll-a (algae): 80.1 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | F (Very Poor) |
| Water Clarity (Secchi Depth) | 2.6 ft |
| Phosphorus | 96 μg/L |
| Chlorophyll-a (Algae) | 80.1 μg/L |
| Maximum Depth | 27 ft |
| Location | Martin County, Minnesota |
How does Hall Lake compare?
With an overall water quality grade of F, Hall Lake falls below the Minnesota state average of Grade C. It ranks #3 of 7 lakes in Martin County by water quality score.
Water clarity (Secchi depth) sits at 2.6 feet. That signals heavy algae or sediment, often tied to high phosphorus from runoff. Algae levels (chlorophyll-a) measure 80.1 µg/L — elevated; risk of harmful algal bloom advisories increases at this concentration.