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LakeQuality

How Clean Is Long Lake?

Long 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): 11.2 ft. Phosphorus: 10 µg/L. Trophic State Index: 40.

Cleanliness Snapshot

MetricLong LakeMinnesota avg
Overall GradeAC
Water Clarity (Secchi)11.2 ft
Phosphorus10 µg/L<30 = clean
Trophic State Index40<50 = clean

How does Long Lake compare?

Long Lake's grade of A matches or beats the Minnesota state average of C. It ranks #30 of 77 lakes in Hubbard County by water quality score. Multi-year monitoring data shows water quality is improving based on 5 years of records.