Day Lake
Vilas County, Wisconsin110 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Day Lake. Here is what has been measured.
- Oligotrophic
- 57 ft max depth
- Public access
- Limited data
Day Lake in Vilas County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Phosphorus: 10.2 µg/L. Maximum depth: 57 ft. Surface area: 110 acres.
Wisconsin DNR lists Panfish as common on Day Lake. DNR survey details →
Day Lake is a 110-acre cold, clear oligotrophic lake in Vilas County, Wisconsin with a maximum depth of 57 feet. Overall water quality is declining over recent sampling years. The lake supports 2 documented fish species including Panfish and Smallmouth Bass. Public access is available with 1 public boat landing. Compared to the 102 other monitored lakes in Vilas County, Day Lake ranks #84 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2022-09-07. Methodology: how these readings are compared.
What Day Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Deep water57 ft surveyed max depth
Swimming conditions
Readings onlyLimited data
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 Day 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 Day Lake
These are the measurements Wisconsin DNR publishes for Day Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Phosphorus 10.2 µg/L. TSI 38.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 10.2µg/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. | 38 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Day Lake
Answers come straight from the public measurements and survey records on this page.
Wisconsin DNR lists Panfish as common on Day Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Day Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is declining. 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. 1 station on file (most recent sample 2022).
Fish Species (DNR-rated)
Lake Details
Max depth
57 ft
Surface area
110 acres
Public access
Yes
Listed by Wisconsin DNR
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Shoreline
2.8 mi
HydroLAKES / HydroSHEDS
Elevation
1,631 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Day LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Day Lake
Compare lakeside cabins, hotels, and vacation rentals near Day 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 Day Lake
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Follow Day Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Day Lake
Water quality readings over time
2 seasons of samples on record (2021–2022). Calling a direction takes at least 4 years of the same measurement.
Phosphorus
Worsening+1.1 µg/L/yr2 years
Nearby Lakes in Vilas County
Frequently asked questions about Day Lake
Where is Day Lake?
- Day 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 Day Lake?
- Day Lake in Vilas County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Phosphorus: 10.2 µg/L. Maximum depth: 57 ft. Surface area: 110 acres.
Is Day Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Day Lake?
- Day Lake has a maximum depth of 57 feet. The lake covers 110 acres.
What fish are in Day Lake?
- Fish species found in Day Lake include Panfish, Smallmouth Bass. Day Lake is located in Vilas County, Wisconsin.
What did the DNR fisheries survey find at Day Lake?
- Wisconsin DNR lists Panfish as common on Day Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Day Lake’s water-quality measurements separately, and the water-quality trend over 2 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Day Lake?
- Day Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Day Lake. Public access is listed as yes.
Can I fish at Day Lake?
- Day Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Wisconsin's fish and wildlife agency, so check its current regulations before you go.
Explore Day Lake across LakeQuality
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Where this data comes from
5 measurements from 1 monitoring station, 2021–2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX5 samples · 2021–2022
Analytical methods
- Phosphorus by Colorimetry
Monitoring station identifiers (1)
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)
Fish and recreation data from Wisconsin DNR Lakes
Named boat-access points from the USGS National Boat Ramps inventory