Is Big Portage (W Bay Lake Safe for Swimming?
Big Portage (W Bay Lake in Cass County, Minnesota has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 8.5 ft visibility. Phosphorus: 18.5 µg/L. Chlorophyll-a (algae): 5.6 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | A (Excellent) |
| Water Clarity (Secchi Depth) | 8.5 ft |
| Phosphorus | 18.5 μg/L |
| Chlorophyll-a (Algae) | 5.6 μg/L |
| Maximum Depth | 23 ft |
| Location | Cass County, Minnesota |
How does Big Portage (W Bay Lake compare?
With an overall water quality grade of A, Big Portage (W Bay Lake matches or beats the Minnesota state average of Grade C. It ranks #60 of 104 lakes in Cass County by water quality score.
Water clarity (Secchi depth) sits at 8.5 feet. That puts the lake in good clarity range, with limited algae interference. Algae levels (chlorophyll-a) measure 5.6 µg/L — low and well within safe swimming guidelines.