Deep Lake
Deep Lake in Adams County, Wisconsin has a water quality grade of B (Good). 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 →
- Clarity
- 15.5 ft
- Typical in July
- 80°F
- Max depth
- 49 ft
- Area
- 33 acres
- Type
- Oligotrophic
- Trend
- → Stable
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Deep Lake is a 33-acre cold, clear oligotrophic lake in Adams County, Wisconsin with a maximum depth of 49 feet. Water quality is graded B based on 1 sampling years through 2026. 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. 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)
Crystal clear, you can see 15.5 ft down. Phosphorus level: 13.2 µg/L. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 15.5 ft | Not graded |
| Phosphorus | 13.2 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay 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
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Water Temperature
Deep Lake typically sits around 80°F at the surface in July. 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.
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 a water-quality grade. LakeQuality grades Deep Lake B from EPA Water Quality Portal chemistry, 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
| Characteristic | Value |
|---|---|
| Maximum Depth | 49 ft |
| Surface Area | 33 acres |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fish Species
Click a species to see every graded 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 data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +1.286 m/yr | 6 |
| Phosphorus | ↓ Declining | +0.7 µg/L/yr | 7 |
County Ranking
Ranked #1 of 18 lakes in Adams County
Nearby Lakes in Adams County
Frequently asked questions about Deep Lake
Where is Deep Lake?
- Deep Lake is a lake in Adams County, Wisconsin. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Deep Lake?
- Deep Lake in Adams County, Wisconsin has a water quality grade of B (Good). 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?
- Good for swimming, clear water with low algae levels. Deep Lake has a water quality grade of B (Good). Always check local health department advisories before swimming.
What is the water temperature of Deep Lake?
- Deep Lake typically sits around 80°F at the surface in July, 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 a water-quality grade. LakeQuality grades Deep Lake B from EPA Water Quality Portal chemistry, 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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Species activity outlook by water temperature and season
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Low nutrients, clear water, excellent for swimming
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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)
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)
Fish and recreation data from Wisconsin DNR Lakes