Is Green Valley Lake Safe for Swimming?
Green Valley Lake in Union County, Wisconsin has a water quality grade of F (Very Poor). Avoid swimming, very poor water quality, potential algae toxins. Water clarity: 1.5 ft visibility. Chlorophyll-a (algae): 61.7 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | F (Very Poor) |
| Water Clarity (Secchi Depth) | 1.5 ft |
| Chlorophyll-a (Algae) | 61.7 μg/L |
| Location | Union County, Wisconsin |
How does Green Valley Lake compare?
With an overall water quality grade of F, Green Valley Lake falls below the Wisconsin state average of Grade D. It ranks #4 of 6 lakes in Union County by water quality score.
Water clarity (Secchi depth) sits at 1.5 feet. That signals heavy algae or sediment, often tied to high phosphorus from runoff. Algae levels (chlorophyll-a) measure 61.7 µg/L — elevated; risk of harmful algal bloom advisories increases at this concentration.