Spider Lake
Spider Lake in Vilas County, Wisconsin has a water quality grade of B (Good). Water clarity: 10.5 ft visibility. Phosphorus: 14.1 µg/L. Maximum depth: 43 ft. Surface area: 278 acres.
Wisconsin DNR lists Musky as common on Spider Lake. DNR survey details →
- Clarity
- 10.5 ft
- Typical in July
- 77°F
- Max depth
- 43 ft
- Area
- 278 acres
- Type
- Mesotrophic
- Trend
- ↑ Improving
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Spider Lake is a 278-acre mesotrophic lake in Vilas County, Wisconsin with a maximum depth of 43 feet. Water quality is graded B based on 1 sampling years through 2025. Overall water quality is improving over recent sampling years. The lake supports 6 documented fish species including Musky, Panfish, and Largemouth Bass. Compared to the 102 other monitored lakes in Vilas County, Spider Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-09-01. 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 10.5 ft. Phosphorus level: 14.1 µg/L. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10.5 ft | Not graded |
| Phosphorus | 14.1 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Spider Lake
Compare lakeside cabins, hotels, and vacation rentals near Spider 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 Spider Lake
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Planning a whole trip? See where to stay at Wisconsin’s top lakes →
Water Temperature
Spider Lake typically sits around 77°F at the surface in July. Summer average is about 74°F. Usually warmest in Jul (about 77°F) and coldest in Apr (about 47°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 12 field readings (2024–2024) via the EPA Water Quality Portal. See the full Spider Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Spider Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (387,258 cells/mL) on April 18, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Wisconsin DNR lists Musky as common on Spider Lake.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Spider Lake B from EPA Water Quality Portal chemistry, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 2006. 1 station on file (most recent sample 2025).
Fish Species (DNR-rated)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 43 ft |
| Surface Area | 278 acres |
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Spider Lake
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.45 m/yr | 5 |
| Phosphorus | ↑ Improving | -1.15 µg/L/yr | 3 |
EPA Impairment Status
Spider Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit WI10027803 · Official waterbody report · Matched by proximity (2.73 km)
County Ranking
Ranked #2 of 103 lakes in Vilas County
Nearby Lakes in Vilas County
Frequently asked questions about Spider Lake
Where is Spider Lake?
- Spider 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 Spider Lake?
- Spider Lake in Vilas County, Wisconsin has a water quality grade of B (Good). Water clarity: 10.5 ft visibility. Phosphorus: 14.1 µg/L. Maximum depth: 43 ft. Surface area: 278 acres.
Is Spider Lake safe to swim in?
- Good for swimming, clear water with low algae levels. Spider Lake has a water quality grade of B (Good). Always check local health department advisories before swimming.
What is the water temperature of Spider Lake?
- Spider Lake typically sits around 77°F at the surface in July, from 12 EPA Water Quality Portal field readings (2024–2024). That is a typical value for the month, not a live reading.
How deep is Spider Lake?
- Spider Lake has a maximum depth of 43 feet. The lake covers 278 acres.
What fish are in Spider Lake?
- Fish species found in Spider Lake include Musky, Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike, Walleye. Spider Lake is located in Vilas County, Wisconsin.
What did the DNR fisheries survey find at Spider Lake?
- Wisconsin DNR lists Musky as common on Spider Lake. A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Spider Lake B from EPA Water Quality Portal chemistry, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Does Spider Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Spider Lake (clouds, ice, or an off-season gap). The most recent reading was high (387,258 cells/mL). Blue-green algae can appear and clear within days, so check Wisconsin's current advisory before swimming.
Explore Spider Lake across LakeQuality
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Fish species and best lakes in Vilas County
Species activity outlook by water temperature and season
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Moderate nutrients, good water quality
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Where this data comes from
30 measurements from 1 monitoring station, 2022–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX30 samples · 2022–2025
Analytical methods
- Phosphorus by Colorimetry
Monitoring station identifiers (1)
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
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Fish and recreation data from Wisconsin DNR Lakes