Is Green Lake Safe for Swimming?
Green Lake in Isanti County, Minnesota has nutrient and algae measurements on record from state and federal monitoring. Chlorophyll-a in the monitoring record runs high enough that algae is a factor. 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: 4.7 ft visibility. Phosphorus: 48 µg/L. Chlorophyll-a (algae): 16.4 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Water Clarity (Secchi Depth) | 4.7 ft |
| Phosphorus | 48 μg/L |
| Chlorophyll-a (Algae) | 16.4 μg/L |
| Maximum Depth | 28 ft |
| Location | Isanti County, Minnesota |
How does Green Lake compare?
With an overall water-quality readings of —, Green Lake runs above the Minnesota state average. It ranks #12 of 17 lakes in Isanti County by water quality score.
Water clarity (Secchi depth) sits at 4.7 feet. That falls into moderate clarity — typical for lakes with some nutrient enrichment. Algae levels (chlorophyll-a) measure 16.4 µg/L — moderate; acceptable for swimming on most days, but worth checking advisories.
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