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LakeQuality

Little Boy Lake in Cass County, Minnesota has nutrient and algae measurements on record from state and federal monitoring. 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: 11 ft visibility. Phosphorus: 14 µg/L. Chlorophyll-a (algae): 5.1 µg/L. Always check local health department advisories before swimming.

Key Metrics

MetricValue
Water Clarity (Secchi Depth)11 ft
Phosphorus14 μg/L
Chlorophyll-a (Algae)5.1 μg/L
Maximum Depth74 ft
LocationCass County, Minnesota

How does Little Boy Lake compare?

With an overall water-quality readings of , Little Boy Lake matches or beats the Minnesota state average. It ranks #36 of 104 lakes in Cass County by water quality score.

Water clarity (Secchi depth) sits at 11 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae. Algae levels (chlorophyll-a) measure 5.1 µg/L — low and well within safe swimming guidelines.