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LakeQuality

How Clean Is Fon-du-Lac Reservoir?

Fon-du-Lac Reservoir has very poor water quality and a high algae bloom risk. It received a water quality grade of F (Very Poor) based on EPA monitoring data. Water clarity (Secchi depth): 1.3 ft. Phosphorus: 81 µg/L. Chlorophyll-a (algae): 40.7 µg/L. Trophic State Index: 69.

Cleanliness Snapshot

MetricFon-du-Lac ReservoirWisconsin avg
Overall GradeFC
Water Clarity (Secchi)1.3 ft
Phosphorus81 µg/L<30 = clean
Chlorophyll-a (Algae)40.7 µg/L<10 = clean
Trophic State Index69<50 = clean

How does Fon-du-Lac Reservoir compare?

Fon-du-Lac Reservoir's grade of F falls below the Wisconsin state average of C. It ranks #7 of 7 lakes in Jefferson County by water quality score.