Calhoun Lake vs Diamond Lake
Water quality, depth, fish species, and recreation comparison.
Calhoun Lake has a higher water quality grade (B, Good) than Diamond Lake (D, Poor). Both are in Kandiyohi County, Minnesota.
Both Calhoun Lake and Diamond 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. Calhoun Lake (B) is materially cleaner than Diamond Lake (D). 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 — Calhoun 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?
Calhoun Lake
Moderate clarity, visible to about 6.9 ft.
Diamond Lake
Murky, only visible to about 5.5 ft.
Side-by-Side Metrics
| Metric | Calhoun Lake | Diamond Lake |
|---|---|---|
| Overall Grade | B (Good) | D (Poor) |
| Water Clarity | 6.9 ft | 5.5 ft |
| Phosphorus | 24 µg/L | 65 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 13 ft | 27 ft |
| Surface Area | 647 acres | 1,610 acres |
| Public Access | Yes | Yes |
| Fish Species | 15 | 15 |
| Trophic State | mesotrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Calhoun Lake wins on overall water quality with a Grade B versus Diamond Lake's Grade D. Water clarity: 6.9 ft vs 5.5 ft. For fishing diversity, Calhoun Lake also leads with 15 species.