Shallow Lake vs Sugar Lake
Water quality, depth, fish species, and recreation comparison.
Shallow Lake has a higher water quality grade (A, Excellent) than Sugar Lake (C, Fair). Both are in Itasca County, Minnesota.
Both Shallow Lake and Sugar Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any grade differences here are about the lakes themselves, not the agencies grading them. The grades are meaningfully apart: Shallow Lake grades a A while Sugar Lake grades a C. 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 — Shallow 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?
Shallow Lake
Crystal clear, you can see 16.4 ft down.
Sugar Lake
Moderate clarity, visible to about 8.4 ft.
Side-by-Side Metrics
| Metric | Shallow Lake | Sugar Lake |
|---|---|---|
| Overall Grade | A (Excellent) | C (Fair) |
| Water Clarity | 16.4 ft | 8.4 ft |
| Phosphorus | 9 µg/L | 18 µg/L |
| Chlorophyll-a (Algae) | 3.2 µg/L | 4.9 µg/L |
| Maximum Depth | 85 ft | 22 ft |
| Surface Area | 539 acres | 1,509 acres |
| Public Access | Yes | Yes |
| Fish Species | 12 | 13 |
| Trophic State | oligotrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Shallow Lake wins on overall water quality with a Grade A versus Sugar Lake's Grade C. Water clarity: 16.4 ft vs 8.4 ft. For more fish-species variety, Sugar Lake edges ahead with 13 documented species.
Source: EPA National Aquatic Resource Surveys, 2026.