Eagle Lake vs Long Lake
Water quality, depth, fish species, and recreation comparison.
Eagle Lake has a higher water quality grade (A, Excellent) than Long Lake (F, Very Poor). Both are in Kandiyohi County, Minnesota.
Eagle Lake and Long 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. Eagle Lake (A) is materially cleaner than Long Lake (F). 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 — Eagle 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?
Eagle Lake
Moderate clarity, visible to about 6.9 ft.
Long Lake
Murky, only visible to about 5 ft.
Side-by-Side Metrics
| Metric | Eagle Lake | Long Lake |
|---|---|---|
| Overall Grade | A (Excellent) | F (Very Poor) |
| Water Clarity | 6.9 ft | 5 ft |
| Phosphorus | 23 µg/L | 92 µg/L |
| Chlorophyll-a (Algae) | 7 µg/L | 42.3 µg/L |
| Maximum Depth | 67 ft | 16 ft |
| Surface Area | 849 acres | 1,573 acres |
| Public Access | Yes | Yes |
| Fish Species | 17 | 16 |
| Trophic State | mesotrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Eagle Lake wins on overall water quality with a Grade A versus Long Lake's Grade F. Water clarity: 6.9 ft vs 5 ft. For fishing diversity, Eagle Lake also leads with 17 species.
Source: EPA National Aquatic Resource Surveys, 2026.