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LakeQuality

Gunflint Lake is among the cleanest lakes in Minnesota. Its nutrient and algae readings come from EPA monitoring data. Water clarity (Secchi depth): 16.5 ft. Phosphorus: 5.5 µg/L. Chlorophyll-a (algae): 2.6 µg/L. Trophic State Index: 35.

Cleanliness Snapshot

MetricGunflint LakeMinnesota avg
Water Clarity (Secchi)16.5 ft
Phosphorus5.5 µg/L<30 = clean
Chlorophyll-a (Algae)2.6 µg/L<10 = clean
Trophic State Index35<50 = clean

How does Gunflint Lake compare?

Gunflint Lake's readings match or beat the Minnesota state average. It ranks #20 of 44 lakes in Cook County by water quality score. Multi-year monitoring data shows water quality is declining based on 5 years of records.