Cedar Lake vs Roberds Lake
Water quality, depth, fish species, and recreation comparison.
Cedar Lake and Roberds Lake both received the same overall water quality grade of F (Very Poor). Both are in Rice County, Minnesota.
Cedar Lake and Roberds 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 close: Cedar Lake (F) and Roberds Lake (F) are within one letter of each other on the LakeGrade rubric. The per-parameter sub-grades below will show where the small differences actually live.
With grades this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.
Cedar Lake
Very murky, less than 2 ft of visibility.
Roberds Lake
Very murky, less than 2.5 ft of visibility.
Side-by-Side Metrics
| Metric | Cedar Lake | Roberds Lake |
|---|---|---|
| Overall Grade | F (Very Poor) | F (Very Poor) |
| Water Clarity | 2 ft | 2.5 ft |
| Phosphorus | 91 µg/L | 300 µg/L |
| Chlorophyll-a (Algae) | 72.6 µg/L | 86.7 µg/L |
| Maximum Depth | 42 ft | 43 ft |
| Surface Area | 902 acres | 632 acres |
| Public Access | Yes | Yes |
| Fish Species | 18 | 18 |
| Trophic State | eutrophic | hypereutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Both lakes earn the same Grade F. The tiebreakers come down to clarity (Cedar Lake: 2 ft, Roberds Lake: 2.5 ft) and what you want from the lake. Cedar Lake matches its peer on species count.
Source: EPA National Aquatic Resource Surveys, 2026.