Blackduck Lake vs Rabideau Lake
Water quality, depth, fish species, and recreation comparison.
Rabideau Lake has a higher water quality grade (C, Fair) than Blackduck Lake (C, Fair). Both are in Beltrami County, Minnesota.
Blackduck Lake and Rabideau 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: Blackduck Lake (C) and Rabideau Lake (C) 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.
Blackduck Lake
Murky, only visible to about 6.2 ft.
Rabideau Lake
Moderate clarity, visible to about 9 ft.
Side-by-Side Metrics
| Metric | Blackduck Lake | Rabideau Lake |
|---|---|---|
| Overall Grade | C (Fair) | C (Fair) |
| Water Clarity | 6.2 ft | 9 ft |
| Phosphorus | 39.5 µg/L | No data |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 28 ft | 112 ft |
| Surface Area | 2.7K acres | 680.35 acres |
| Public Access | Yes | Yes |
| Fish Species | 1 | 1 |
| Trophic State | eutrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Rabideau Lake wins on overall water quality with a Grade C versus Blackduck Lake's Grade C. Water clarity: 9 ft vs 6.2 ft. For fishing diversity, Rabideau Lake also leads with 1 species.