Crab Lake
Crab Lake in Vilas County, Wisconsin has a water quality grade of B (Good). Water clarity: 11 ft visibility. Phosphorus: 12.6 µg/L.
- Clarity
- 11 ft
- Max depth
- ~88 ft est.
- Type
- Mesotrophic
- Trend
- → Stable
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Crab Lake is a mesotrophic lake in Vilas County, Wisconsin with an estimated average depth of about 88 feet. Water quality is graded B based on 1 sampling years through 2025. Water clarity is improving over recent sampling years. Compared to the 102 other monitored lakes in Vilas County, Crab Lake ranks #38 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-07-19. Grade methodology: LakeQuality methodology.
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Swimming Safety
Grade onlyLow algae
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Good for swimming, clear water with low algae levels
Water Quality Grade: B (Good)
Good clarity, visible to about 11 ft. Phosphorus level: 12.6 µg/L. Trophic State Index: 42.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 11 ft | Not graded |
| Phosphorus | 12.6 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 42 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Crab Lake
Compare lakeside cabins, hotels, and vacation rentals near Crab Lake in Vilas County, Wisconsin — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Crab Lake
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DNR Reports & Resources
Wisconsin DNR Fisheries scientists publish multi-year survey reports for Crab Lake covering fish populations, stocking, water quality, and management. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- 2024Crab Lake spring survey, 2024Fisheries Survey · WI DNR · 2024 (PDF)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~88 ft est. |
| Average Depth | ~28 ft est. |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Wisconsin has not published bathymetry for Crab Lake.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Fishing Crab Lake
Water Quality Trend: → Stable
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +1 m/yr | 3 |
| Phosphorus | ↓ Declining | +2.41 µg/L/yr | 5 |
County Ranking
Ranked #38 of 103 lakes in Vilas County
Nearby Lakes in Vilas County
Frequently asked questions about Crab Lake
Where is Crab Lake?
- Crab Lake is a lake in Vilas County, Wisconsin. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Crab Lake?
- Crab Lake in Vilas County, Wisconsin has a water quality grade of B (Good). Water clarity: 11 ft visibility. Phosphorus: 12.6 µg/L.
Is Crab Lake safe to swim in?
- Good for swimming, clear water with low algae levels. Crab Lake has a water quality grade of B (Good). Always check local health department advisories before swimming.
How deep is Crab Lake?
- No published bathymetric survey covers Crab Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 88 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
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Where this data comes from
31 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX31 samples · 2020–2025
Analytical methods
- Phosphorus by Colorimetry
Monitoring station identifiers (2)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)