Skip to main content
LakeQuality

Pleasant Lake and Stony Lake read the same on nutrients and algae. Both are in Cass County, Minnesota.

Reviewed by LakeQuality Editorial Team · Updated

Pleasant Lake and Stony Lake are both in Minnesota — a same-state head-to-head where the comparison comes down to lake-specific differences in depth, watershed, and monitoring history rather than the broader state-level water-quality regime. The readings are close: Pleasant Lake and Stony Lake sit within a narrow band of each other on phosphorus, chlorophyll-a and clarity. The per-parameter table below shows where the small differences actually live.

With readings this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.

Pleasant Lake

Cass County, Minnesota

Crystal clear, you can see 15.5 ft down.

Stony Lake

Cass County, Minnesota

Crystal clear, you can see 23 ft down.

Side-by-Side Metrics

MetricPleasant LakeStony Lake
Water Clarity15.5 ft23 ft Better
Phosphorus10 µg/L7 µg/L Better
Chlorophyll-a (Algae)3.1 µg/L2 µg/L Better
Maximum Depth72 ft Better50 ft
Surface Area1,099 acres563 acres
Public AccessYesYes
Fish Species15 Better12
Trophic Stateoligotrophicoligotrophic

A green ✓ marks the better value for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better). Surface area and trophic state carry no tick — a bigger lake is not a better lake.

Verdict

Both lakes earn the same Grade A. The tiebreakers come down to clarity (Pleasant Lake: 15.5 ft, Stony Lake: 23 ft) and what you want from the lake. Pleasant Lake supports more documented fish species.

Source: EPA National Aquatic Resource Surveys, 2026.