
Jefferson Lake vs Washington Lake
Water quality, depth, fish species, and recreation comparison.
Jefferson Lake and Washington Lake read the same on nutrients and algae. Both are in Le Sueur County, Minnesota.
Jefferson Lake and Washington 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: Jefferson Lake and Washington 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.
Jefferson Lake
Very murky, less than 2 ft of visibility.
Washington Lake
Murky, only visible to about 4.5 ft.
Side-by-Side Metrics
| Metric | Jefferson Lake | Washington Lake |
|---|---|---|
| Water Clarity | 2 ft | 4.5 ft Better |
| Phosphorus | 86.5 µg/L Better | 122 µg/L |
| Chlorophyll-a (Algae) | 72 µg/L | 51.3 µg/L Better |
| Maximum Depth | - | 51 ft |
| Surface Area | 700 acres | 1,516 acres |
| Public Access | Yes | Yes |
| Fish Species | 0 | 18 Better |
| Trophic State | eutrophic | eutrophic |
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.
Swap a lake
Compare Jefferson Lake or Washington Lake against a different lake.
Verdict
Both lakes earn the same Grade F. The tiebreakers come down to clarity (Jefferson Lake: 2 ft, Washington Lake: 4.5 ft) and what you want from the lake. Jefferson Lake has fewer fish species than Washington Lake.
Source: EPA National Aquatic Resource Surveys, 2026.