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LakeQuality

How Clean Is Stony Lake?

Stony Lake is among the cleanest lakes in Minnesota. It received a water quality grade of A (Excellent) based on EPA monitoring data. Water clarity (Secchi depth): 23.3 ft. Phosphorus: 7 µg/L. Trophic State Index: 32.

Cleanliness Snapshot

MetricStony LakeMinnesota avg
Overall GradeAC
Water Clarity (Secchi)23.3 ft
Phosphorus7 µg/L<30 = clean
Trophic State Index32<50 = clean

How does Stony Lake compare?

Stony Lake's grade of A matches or beats the Minnesota state average of C. It ranks #26 of 133 lakes in Cass County by water quality score. Multi-year monitoring data shows water quality is improving based on 5 years of records.