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Twin Bear Lake
Enhanced dataInteractive depth contours
Twin Bear LakeBayfield County, WI
Contours load with map Access
Interactive depth contours5-foot typical interval · Sonar-derived depth (C-MAP Genesis) · Gaps interpolated · Not for navigation
Source: C-MAP Genesis community sonar (derived)high confidence · QA passed · Select a contour to inspect its mapped depthDepths decoded from C-MAP Genesis Social Map community sonar recordings (used with permission), covering 99% of the lake. Small gaps between recordings are smoothly connected; larger unrecorded areas follow the lake's depth model calibrated to the DNR-documented 59-ft maximum depth. More accurate than a pure model, but still an estimate. Not for navigation.LakeList assistant
Plan your lake day
Fishing spots, food, lodging, marinas, and rentals around Twin Bear Lake.
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Fishing forecast
Best windows for Twin Bear 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
Twin Bear Lake water temperature today
Modeled surface-temperature estimate built from seasonal climate, lake depth, and live National Weather Service air temperatures near this lake.
71°FWarm
Seasonal estimate. Checking current National Weather Service air temperatures…
Comfortable summer pattern. Bass and panfish are active; early and late hours beat the midday heat.
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 Twin Bear Lake - Deep Hole.
Last sampled Aug 2025Volunteer monitoring since 1993
Through 2025, very clear water — summer clarity of 19.8 ft puts it among the clearest tenth of monitored Wisconsin lakes.
Based on July–August 2025 averages across 3 volunteer readings.Water claritySecchi disk depth
19.8 ftJul–Aug 2025 avg (3 readings)
Crystal clearStable since 2011
Clearer than 97% of 596 monitored Wisconsin lakes with current readings.
No recent algae readings — last measured 2007. No recent nutrient readings — last measured 2008.
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 | 19.8 ft (3) | — | — |
| 2024 | 18.0 ft (1) | — | — |
| 2023 | 19.3 ft (6) | — | — |
| 2015 | 19.0 ft (3) | — | — |
| 2014 | 18.6 ft (2) | — | — |
| 2013 | 19.4 ft (4) | — | — |
| 2012 | 17.1 ft (5) | — | — |
| 2011 | 21.1 ft (5) | — | — |
| 2010 | 17.2 ft (4) | — | — |
| 2009 | 19.4 ft (3) | — | — |
Latest individual samples: Secchi 23 ft (2025-08-29), chlorophyll-a 4 µg/L (2007-11-08), and total phosphorus 15 µg/L (2008-02-21).
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.
Twin Bear Lake - Deep HoleStation 043127
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 sheetFishing 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
Twin Bear Lake depth maps
1 converted map sheet. These historical surveys are not for navigation.
Navigable depth map
Twin Bear 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 2903100 · 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.
157surface acres
59max depth feet
1public access points
46.5058, -91.3673latitude, longitude
Access
Public access points
Boat launchTwin Bear County Park46.50843, -91.35873Managed by COUNTYTOWN OF IRON RIVERRamp surface: ConcreteADA-accessible feature: NoVerified 2026-07-12
Nearby
Trip-planning places
No nearby trip-planning places yet
Fishery
Notable species
Largemouth BassPanfishSmallmouth BassWalleyeMuskyNorthern Pike
Wisconsin DNR stocking
Fish stocking history
The latest published year is 2024, when 456 fish were recorded across 1 entry.
2024
MuskellungeGreat Lakes Spotted · Large Fingerling
45611.5 in average
2022
MuskellungeGreat Lakes Spotted · Large Fingerling
3929.5 in average
2018
MuskellungeUpper Chippewa River · Large Fingerling
48811.8 in average
2016
MuskellungeUpper Chippewa River · Large Fingerling
28211.7 in average
2014
MuskellungeUpper Chippewa River · Large Fingerling
47211.4 in average
2012
MuskellungeUpper Chippewa River · Large Fingerling
47213.3 in average
2010
MuskellungeUpper Wisconsin River · Large Fingerling
35512.4 in average
Depth FAQ
How deep is Twin Bear Lake?
Twin Bear Lake is 59 feet deep at its deepest point and averages about 23 feet, according to Wisconsin DNR records.
Is there a free depth map of Twin Bear Lake?
Yes. LakeList publishes a free interactive depth contour map of Twin Bear Lake at a typical 5-foot interval, with an optional 3D underwater view, derived from C-MAP Genesis community sonar (derived) survey data.
Where does the Twin Bear Lake depth map come from?
The interactive depth contours are derived from C-MAP Genesis community sonar (derived). Each contour set passes a visual QA review against the source document before it is published. The depths are derived from community sonar recordings (C-MAP Genesis Social Map, used with permission), with gaps between recordings interpolated; not for navigation.
Trust and freshness
Where this lake data comes from
Wisconsin DNR Lake Pagesname, coordinates, county, source identifiers
LakeList record updated 2026-05-25
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