Skip to main content
LakeQuality

Minnetonka Lake vs Sarah Lake

Water quality, depth, fish species, and recreation comparison.

Minnetonka Lake has a higher water quality grade (B, Good) than Sarah Lake (D, Poor). Both are in Hennepin County, Minnesota.

Both Minnetonka Lake and Sarah Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any grade differences here are about the lakes themselves, not the agencies grading them. Minnetonka Lake (B) is materially cleaner than Sarah Lake (D). A gap that wide is unlikely to close in a single year of remediation work; it reflects multi-decade differences in the lakes themselves.

For a recreational visitor, the wider grade gap is decisive — Minnetonka Lake is the better water-quality choice. For a researcher, the gap is the interesting part: what is different about the two watersheds, and which of those differences is mutable?

B

Minnetonka Lake

Hennepin County, Minnesota

Moderate clarity, visible to about 9.5 ft.

D

Sarah Lake

Hennepin County, Minnesota

Very murky, less than 3 ft of visibility.

Side-by-Side Metrics

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

Source: EPA National Aquatic Resource Surveys, 2026.

MetricMinnetonka LakeSarah Lake
Overall GradeB (Good)D (Poor)
Water Clarity9.5 ft3 ft
Phosphorus27 µg/L78 µg/L
Chlorophyll-a (Algae)No dataNo data
Maximum Depth113 ft59 ft
Surface Area14.2K acres557.23 acres
Public AccessYesYes
Fish Species11
Trophic Statemesotrophiceutrophic

Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).

Verdict

Minnetonka Lake wins on overall water quality with a Grade B versus Sarah Lake's Grade D. Water clarity: 9.5 ft vs 3 ft. For fishing diversity, Minnetonka Lake also leads with 1 species.