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Halfmoon Lake
Enhanced dataInteractive depth contours
Halfmoon LakeLincoln County, WI
Contours load with map Access
Interactive depth contours5-foot typical interval · Modeled depth estimate · Not a survey · Not for navigation
Source: LakeList depth modelmedium confidence · QA passed · Select a contour to inspect its mapped depthModeled depth estimate: contours computed from the lake's shoreline shape and its documented 14-ft maximum depth (depth grows with distance from shore, calibrated to the documented mean depth where available). This is a smooth mathematical model, not a survey - real holes, bars, and drop-offs will differ. Community sonar (C-MAP Genesis) overlays where recorded. Not for navigation.LakeList assistant
Plan your lake day
Fishing spots, food, lodging, marinas, and rentals around Halfmoon Lake.
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Fishing forecast
Best windows for Halfmoon Lake
Weather-based planning built from the National Weather Service hourly forecast near this lake.
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Checking wind, precipitation, and near-term weather windows.
Water temperature
Halfmoon Lake water temperature today
Modeled surface-temperature estimate built from seasonal climate, lake depth, and live National Weather Service air temperatures near this lake.
77°FPeak summer
Seasonal estimate. Checking current National Weather Service air temperatures…
Warmest water of the year. Fish hold deeper or feed in low light; swimming and watersports are at their best.
Estimates are modeled, not measured. Actual temperatures vary with depth, wind mixing, and recent weather — verify conditions before swimming, boating, or heading onto ice.
DNR water check
Water quality quick take
From Wisconsin DNR / Citizen Lake Monitoring readings at Halfmoon Lake - Deep Hole.
Sampled Aug 2025Volunteer monitoring since 1999
Murky water — summer clarity of 2.8 ft is lower than most monitored Wisconsin lakes.
Based on July–August volunteer averages from 2024–2025; each value shows its own year.49Mesotrophic5-yr summer TSI
Moderately clear with moderate nutrients — a typical profile for good swimming lakes.
Water claritySecchi disk depth
2.8 ftJul–Aug 2024 avg (2 readings)
MurkyDeclining — down ~25% vs earlier years
Clearer than 37% of 596 monitored Wisconsin lakes with current readings.
AlgaeChlorophyll-a
5.5 µg/LJul–Aug 2025 avg (2 readings)
ModerateWorsening — up ~115% vs earlier years
No recent nutrient readings — last measured 2012.
All readings by year · station details · methodology
Summer averages (July/August)
July/August means; counts in parentheses show how many samples went into each average.
| Year | Secchi | Chlorophyll-a | Total phosphorus |
|---|---|---|---|
| 2025 | 7.0 ft (1) | 5.5 µg/L (2) | — |
| 2024 | 2.8 ft (2) | 23.0 µg/L (2) | — |
| 2023 | 6.0 ft (2) | — | — |
| 2022 | 7.3 ft (4) | 7.0 µg/L (2) | — |
| 2021 | 7.6 ft (2) | 5.0 µg/L (1) | — |
| 2020 | 6.0 ft (1) | 7.0 µg/L (1) | — |
| 2019 | — | 4.5 µg/L (2) | — |
| 2018 | 7.7 ft (3) | 6.5 µg/L (2) | — |
| 2017 | 7.0 ft (2) | 8.0 µg/L (2) | — |
| 2016 | 8.5 ft (6) | 9.0 µg/L (1) | — |
Latest individual samples: Secchi 7 ft (2025-08-27), chlorophyll-a 4 µg/L (2025-08-27), and total phosphorus 25 µg/L (2012-09-05).
Secchi clarity is how deep a black-and-white disk stays visible from the surface — more feet means clearer water.
Chlorophyll-a is an algae pigment; higher values signal more algae in the water column.
Total phosphorus is a nutrient that feeds algae and aquatic plants. It is not a weed survey — depth, bottom type, water movement, and management change the actual lake experience.
Halfmoon Lake - Deep HoleStation 353091 · TSI based on Secchi
Modeled from DNR/CLMN monitoring — not a safety or swim-condition report. Verify current conditions locally. LakeList verified 2026-07-12.Official Wisconsin information
Plan with DNR sources
LakeList links to the authoritative record so you can verify maps, rules, and current notices before leaving.
Historical DNR depth maps1 converted map sheetView DNR depth mapHistorical map · not for navigationFishing regulationsVerify current seasons, limits, and restrictionsOfficial DNR lake pageFacts, advisories, boating, and water qualityWater quality reportsMonitoring stations, clarity, and DNR reportsInvasive speciesVerified, observed, and historical AIS recordsBoating ordinancesLocal slow-no-wake and water-use restrictionsFish consumption advisoriesStatewide and waterbody-specific health guidance
Historical depth maps are not for navigation. Verify regulations and access at the official source before your trip.
Historical Wisconsin DNR maps
Halfmoon Lake depth maps
1 converted map sheet. These historical surveys are not for navigation.
Navigable depth map
Halfmoon Lake · sheet 1
Pan, zoom, and inspect the converted Wisconsin DNR historical map image in the browser. Historical survey — not for navigation.
Source: Wisconsin DNR · WBIC 988000 · image navigation only; spatial alignment pending · Historical lake maps are not for navigation.
Source: Wisconsin Department of Natural Resources. Converted for browser access with source URLs, checksums, and retrieval dates retained. Historical lake maps are not for navigation.
102surface acres
14max depth feet
1public access points
45.5241, -89.7302latitude, longitude
Access
Public access points
Boat launchHalfmoon Lake Ramp45.52634, -89.73827Managed by TOWNSHIPTOWN OF BRADLEYRamp surface: Concrete PlankADA-accessible feature: NoVerified 2026-07-12
Nearby
Trip-planning places
No nearby trip-planning places yet
Fishery
Notable species
Largemouth BassPanfishNorthern Pike
Depth FAQ
How deep is Halfmoon Lake?
Halfmoon Lake is 14 feet deep at its deepest point and averages about 5 feet, according to Wisconsin DNR records.
Is there a free depth map of Halfmoon Lake?
Yes. LakeList publishes a free interactive depth contour map of Halfmoon Lake at a typical 5-foot interval, with an optional 3D underwater view, derived from LakeList depth model survey data.
Where does the Halfmoon Lake depth map come from?
The interactive depth contours are derived from LakeList depth model. Each contour set passes a visual QA review against the source document before it is published. The depths are a modeled estimate calibrated to the lake's documented maximum depth - not a survey, and not for navigation.
Trust and freshness
Where this lake data comes from
Wisconsin DNR Lake Mapsname, coordinates, county, source identifiers
LakeList record updated 2026-07-14
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