Mazaska Lake vs Roberds Lake
Water quality, depth, fish species, and recreation comparison.
Mazaska Lake and Roberds Lake read the same on nutrients and algae. Both are in Rice County, Minnesota.
Both Mazaska Lake and Roberds Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any differences in the readings here are about the lakes themselves, not the agencies sampling them. These two sit close on the readings, Mazaska Lake versus Roberds Lake. The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.
With readings 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.
Mazaska Lake
Very murky, less than 2.5 ft of visibility.
Roberds Lake
Very murky, less than 2.5 ft of visibility.
Side-by-Side Metrics
| Metric | Mazaska Lake | Roberds Lake |
|---|---|---|
| Water Clarity | 2.5 ft | 2.5 ft |
| Phosphorus | 89 µg/L Better | 300 µg/L |
| Chlorophyll-a (Algae) | 51.3 µg/L Better | 86.7 µg/L |
| Maximum Depth | 50 ft Better | 43 ft |
| Surface Area | 688 acres | 632 acres |
| Public Access | Yes | Yes |
| Fish Species | 17 | 18 Better |
| Trophic State | eutrophic | hypereutrophic |
A green ✓ marks the better value for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better). Surface area and trophic state carry no tick — a bigger lake is not a better lake.
Swap a lake
Compare Mazaska Lake or Roberds Lake against a different lake.
Verdict
Both lakes earn the same Grade F. The tiebreakers come down to clarity (Mazaska Lake: 2.5 ft, Roberds Lake: 2.5 ft) and what you want from the lake. Mazaska Lake has fewer fish species than Roberds Lake.
Source: EPA National Aquatic Resource Surveys, 2026.