Lac Courte Oreilles Lake vs Spider Lake
Water quality, depth, fish species, and recreation comparison.
Lac Courte Oreilles Lake has a higher water quality grade (A, Excellent) than Spider Lake (B, Good). Both are in Sawyer County, Wisconsin.
Both Lac Courte Oreilles Lake and Spider Lake sit in Wisconsin. A same-state comparison strips out the state-level water-quality regime as a variable: any grade differences here are about the lakes themselves, not the agencies grading them. These two are within a letter of each other on the rubric — Lac Courte Oreilles Lake (A) versus Spider Lake (B). The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.
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.
Lac Courte Oreilles Lake
Good clarity, visible to about 12.2 ft.
Spider Lake
Good clarity, visible to about 10.5 ft.
Side-by-Side Metrics
| Metric | Lac Courte Oreilles Lake | Spider Lake |
|---|---|---|
| Overall Grade | A (Excellent) | B (Good) |
| Water Clarity | 12.2 ft | 10.5 ft |
| Phosphorus | 15 µg/L | 14.1 µg/L |
| Chlorophyll-a (Algae) | 1.7 µg/L | No data |
| Maximum Depth | 90 ft | 64 ft |
| Surface Area | 5,139 acres | 1,194 acres |
| Public Access | Yes | Yes |
| Fish Species | 6 | 5 |
| Trophic State | mesotrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Lac Courte Oreilles Lake wins on overall water quality with a Grade A versus Spider Lake's Grade B. Water clarity: 12.2 ft vs 10.5 ft. For fishing diversity, Lac Courte Oreilles Lake also leads with 6 species.
Source: EPA National Aquatic Resource Surveys, 2026.