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LakeQuality

Is Duncan Lake Safe for Swimming?

Duncan Lake in Cook County, Minnesota has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 22 ft visibility. Always check local health department advisories before swimming.

Key Metrics

MetricValue
Overall GradeA (Excellent)
Water Clarity (Secchi Depth)22 ft
Maximum Depth130 ft
LocationCook County, Minnesota

How does Duncan Lake compare?

With an overall water quality grade of A, Duncan Lake matches or beats the Minnesota state average of Grade C. It ranks #10 of 128 lakes in Cook County by water quality score.

Water clarity (Secchi depth) sits at 22 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae.