Agnes Lake vs Lac la Croix Lake
Water quality, depth, fish species, and recreation comparison.
Agnes Lake has a higher water quality grade (B, Good) than Lac la Croix Lake (F, Very Poor). Both are in St. Louis County, Minnesota.
Agnes Lake and Lac la Croix 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 grades are meaningfully apart: Agnes Lake grades a B while Lac la Croix Lake grades a F. That two-letter spread reflects real underlying differences — different watershed inputs, different depth profiles, or different monitoring rigor.
For a recreational visitor, the wider grade gap is decisive — Agnes 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?
Agnes Lake
Good clarity, visible to about 11 ft.
Lac la Croix Lake
Very murky, less than 2.5 ft of visibility.
Side-by-Side Metrics
| Metric | Agnes Lake | Lac la Croix Lake |
|---|---|---|
| Overall Grade | B (Good) | F (Very Poor) |
| Water Clarity | 11 ft | 2.5 ft |
| Phosphorus | No data | No data |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 30 ft | 30 ft |
| Surface Area | 1.0K acres | 1.0K acres |
| Public Access | No | No |
| Fish Species | 10 | 10 |
| Trophic State | mesotrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Agnes Lake wins on overall water quality with a Grade B versus Lac la Croix Lake's Grade F. Water clarity: 11 ft vs 2.5 ft. For fishing diversity, Agnes Lake also leads with 10 species.