Big Portage (W Bay Lake vs Long Lake
Water quality, depth, fish species, and recreation comparison.
Long Lake has a higher water quality grade (A, Excellent) than Big Portage (W Bay Lake (B, Good). Both are in Cass County, Minnesota.
Big Portage (W Bay Lake and Long 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: Big Portage (W Bay Lake (B) and Long Lake (A) 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.
Big Portage (W Bay Lake
Moderate clarity, visible to about 7.5 ft.
Long Lake
Crystal clear, you can see 21.5 ft down.
Side-by-Side Metrics
| Metric | Big Portage (W Bay Lake | Long Lake |
|---|---|---|
| Overall Grade | B (Good) | A (Excellent) |
| Water Clarity | 7.5 ft | 21.5 ft |
| Phosphorus | 20 µg/L | 9 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 23 ft | 115 ft |
| Surface Area | 902.34 acres | 1.0K acres |
| Public Access | Yes | Yes |
| Fish Species | 1 | 1 |
| Trophic State | mesotrophic | oligotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Long Lake wins on overall water quality with a Grade A versus Big Portage (W Bay Lake's Grade B. Water clarity: 21.5 ft vs 7.5 ft. For fishing diversity, Long Lake also leads with 1 species.