Best Lakes for Swimming Near Mankato
Minnesota
4 swimming lakes within driving distance of Mankato, Minnesota, ranked by water quality and swimming-specific filters. Filtered for grade A or B water quality, low algae (chlorophyll-a under 15 µg/L), and public access. Always check local advisories on the day you swim.
Mankato is not lake-dense — only 4 graded lakes are within easy reach. The cleanest of those is Fish Lake (A).
The swimming-specific ranking layered on top of the LakeGrade rubric is what produces the list below: a grade-good lake that does not also support the swimming use case is less useful than a grade-decent lake that does.
| # | Lake | County | Grade | Distance | Clarity | Depth |
|---|---|---|---|---|---|---|
| 1 | Fish Lake | Le Sueur | A | 17.1 mi | 11.8 ft | - |
| 2 | Unnamed Lake | Blue Earth | B | 3.3 mi | - | - |
| 3 | Roemhildts Lake | Le Sueur | B | 15.2 mi | 10.2 ft | - |
| 4 | Unnamed Lake | Nicollet | B | 12.2 mi | 5 ft | - |
Other activities near Mankato
Source: EPA National Aquatic Resource Surveys, 2026.