Crab Lake
Vilas County, WisconsinView mapDirections
Wisconsin DNR publishes the water-quality measurements for Crab Lake. Here is what has been measured.
- Mesotrophic
- 88 ft max depth
Crab Lake in Vilas County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 11 ft visibility. Phosphorus: 12.6 µg/L.
Crab Lake is a mesotrophic lake in Vilas County, Wisconsin with an estimated average depth of about 88 feet. 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. Methodology: how these readings are compared.
Vrbo is where to look for cabins and lake homes around Crab Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Crab Lake is good for
From access and monitoring records, not editorial picks.
- Clear water11 ft of visibility
Swimming conditions
Readings onlyLow algae
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Crab Lake is safe to swim in today is a call for the Wisconsin Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Crab Lake
These are the measurements Wisconsin DNR publishes for Crab Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 11 ft. Phosphorus 12.6 µg/L. TSI 42.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 11ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 12.6µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 42 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Crab Lake
Answers come straight from the public measurements and survey records on this page.
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
Max depth
~88 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
Watershed (drainage) area
20 sq mi
HydroLAKES / HydroSHEDS
Surface area
897 acres
HydroLAKES / HydroSHEDS
Shoreline
9.8 mi
HydroLAKES / HydroSHEDS
Elevation
1,640 ft
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.
Stays via Stay22
Stays 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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Fishing Crab Lake
Water Quality Trend: Stable
Based on 5 years of monitoring (2020–2025).
Water clarity
Improving3 years
Phosphorus
Worsening+2.41 µg/L/yr5 years
Nearby Lakes in Vilas County
Frequently asked questions about Crab Lake
Where is Crab Lake?
- Crab Lake is a lake in Vilas County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Crab Lake?
- Crab Lake in Vilas County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 11 ft visibility. Phosphorus: 12.6 µg/L.
Is Crab Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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.
Explore Crab Lake across LakeQuality
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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)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)