Eagle Lake
Crow Wing County, MinnesotaMesotrophic
Eagle Lake comes in at a B on the grading rubric — a respectable showing for a Minnesota lake of its size and depth. Secchi readings are the weakest of the three parameters, suggesting suspended sediment or algal biomass dominates the optical signal.
A TSI near 45 places Eagle Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Within Crow Wing County's 120 graded lakes, Eagle Lake ranks 75 — below the local median, though not at the bottom.
Zebra mussel presence at Eagle Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. The state fisheries records do not list documented species for Eagle Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. Public access is available — the lake is on the Minnesota PCA public-access list. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-09-19. Grade methodology: LakeGrade methodology.
Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Moderate clarity, visible to about 9.5 ft. Phosphorus level: 17.5 µg/L. Trophic State Index: 45.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 9.5 ft | C |
| Phosphorus | 17.5 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 45 | Mesotrophic |
Moderate nutrients, good water quality
Invasive Species
Water Quality Trend: → Stable
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.151 m/yr | 5 |
| Phosphorus | ↑ Improving | -1.7 µg/L/yr | 5 |
Location
County Ranking
Ranked #75 of 120 lakes in Crow Wing County
Nearby Lakes in Crow Wing County
More Minnesota Lake Rankings
State Parks Near Eagle Lake
Other Grade B Lakes in Minnesota
Mesotrophic Lakes in Minnesota
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Eagle Lake. 1 report on file.
- —Public Water Access Sites — Eagle (Main Bay)Public Water Access Sites · MN DNR LakeFinder
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2024-09-19
Monitoring stations: 3