Deep Lake
Adams County, Wisconsin33 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Deep Lake. Here is what has been measured.
- Oligotrophic
- Curly-Leaf Pondweed
- 49 ft max depth
Deep Lake in Adams County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 15.5 ft visibility. Phosphorus: 13.2 µg/L. Maximum depth: 49 ft. Surface area: 33 acres.
Wisconsin DNR lists Largemouth Bass as common on Deep Lake. DNR survey details →
Deep Lake is a 33-acre cold, clear oligotrophic lake in Adams County, Wisconsin with a maximum depth of 49 feet. Water clarity is improving over recent sampling years. The lake supports 4 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Compared to the 17 other monitored lakes in Adams County, Deep Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-06-10. Methodology: how these readings are compared.
Deep Lake covers about 33 acres in Adams County. Vrbo is where to look for cabins and lake homes around Deep Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Deep Lake is good for
From access and monitoring records, not editorial picks.
- Clear water15.5 ft of visibility
- Fishing4 species recorded
- Deep water49 ft surveyed max depth
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 Deep 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 Deep Lake
These are the measurements Wisconsin DNR publishes for Deep Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 15.5 ft down. Phosphorus 13.2 µg/L. TSI 39.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 15.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 13.2µg/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. | 39 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Deep Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Deep Lake typically sits around 76°F at the surface in September. Summer average is about 78°F. Usually warmest in Jul (about 80°F) and coldest in Mar (about 42°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (42°F) to its warmest (80°F).
Typical surface water temperature by month, from 10 field readings (2024–2024) via the EPA Water Quality Portal.
Wisconsin DNR lists Largemouth Bass as common on Deep Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Deep Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is stable. 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 2004. 1 station on file (most recent sample 2025).
Fish Species (DNR-rated)
Lake Details
Max depth
49 ft
Surface area
33 acres
Lake Size & Watershed
Watershed (drainage) area
0 sq mi
HydroLAKES / HydroSHEDS
Shoreline
1.1 mi
HydroLAKES / HydroSHEDS
Elevation
928 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Deep Lake
Compare lakeside cabins, hotels, and vacation rentals near Deep Lake in Adams 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 Deep Lake
Prices for Oct 16–18, 4 adults. Change dates on the map below.
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Fish Species
Click a species to see every lake where it is documented.
Fishing Deep 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: Stable
Based on 7 years of monitoring (2020–2026).
Water clarity
Improving6 years
Phosphorus
Worsening+0.7 µg/L/yr7 years
Nearby Lakes in Adams County
Frequently asked questions about Deep Lake
Where is Deep Lake?
- Deep Lake is a lake in Adams County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Deep Lake?
- Deep Lake in Adams County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 15.5 ft visibility. Phosphorus: 13.2 µg/L. Maximum depth: 49 ft. Surface area: 33 acres.
Is Deep Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Deep Lake?
- Deep Lake typically sits around 76°F at the surface in September, from 10 EPA Water Quality Portal field readings (2024–2024). That is a typical value for the month, not a live reading.
How deep is Deep Lake?
- Deep Lake has a maximum depth of 49 feet. The lake covers 33 acres.
What fish are in Deep Lake?
- Fish species found in Deep Lake include Panfish, Largemouth Bass, Northern Pike, Trout. Deep Lake is located in Adams County, Wisconsin.
What did the DNR fisheries survey find at Deep Lake?
- Wisconsin DNR lists Largemouth Bass as common on Deep Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Deep Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
Explore Deep Lake across LakeQuality
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Where this data comes from
44 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX44 samples · 2020–2026
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