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Long Lake
Enhanced dataInteractive depth contours
Long LakeFlorence 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 21-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 Long Lake.
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Fishing forecast
Best windows for Long 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
Long Lake water temperature today
Modeled surface-temperature estimate built from seasonal climate, lake depth, and live National Weather Service air temperatures near this lake.
74°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 Long Lake - Deep Hole.
Sampled Sep 2025Volunteer monitoring since 2007
Somewhat hazy water — summer clarity of 7.8 ft is clearer than most monitored Wisconsin lakes.
Based on July–August 2025 averages across 4 volunteer readings.51Eutrophic5-yr summer TSI
Nutrient-rich, greener water — more algae and plant growth, common in shallower lakes.
Water claritySecchi disk depth
7.8 ftJul–Aug 2025 avg (2 readings)
Slight hazeStable since 2009
Clearer than 56% of 596 monitored Wisconsin lakes with current readings.
AlgaeChlorophyll-a
9 µg/LJul–Aug 2025 avg (2 readings)
ModerateStable since 2009
NutrientsTotal phosphorus — fuels plant & algae growth
23 µg/LLatest single sample · 2023-08-31
ModerateModerate phosphorus can support noticeable plant/algae growth.
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 | 7.8 ft (2) | 9.0 µg/L (2) | — |
| 2024 | 7.5 ft (2) | 7.5 µg/L (2) | — |
| 2023 | 6.0 ft (1) | 6.0 µg/L (2) | 23.0 µg/L (1) |
| 2022 | 8.4 ft (3) | 6.0 µg/L (3) | — |
| 2013 | 6.0 ft (1) | — | — |
| 2012 | 10.0 ft (1) | — | — |
| 2011 | 7.0 ft (1) | — | — |
| 2009 | 6.5 ft (1) | 9.0 µg/L (2) | — |
| 2008 | 7.5 ft (1) | — | — |
| 2007 | 7.0 ft (3) | — | — |
Latest individual samples: Secchi 10 ft (2025-09-18), chlorophyll-a 6 µg/L (2025-09-18), and total phosphorus 23 µg/L (2023-08-31).
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.
Long Lake - Deep HoleStation 193014 · TSI based on chlorophyll
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 maps2 converted map sheetsFishing 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
Long Lake depth maps
2 converted map sheets. These historical surveys are not for navigation.
Navigable depth map
Long 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 677400 · 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.
Wisconsin DNR · 2026–2027 season
Lake-specific fishing regulations
Rule text published by the DNR for this waterbody, cached by WBIC and verified 2026-07-12.
All species
This lake may be in more than 1 county. Follow the trolling regulations for the county in which you are fishing. A list of counties and waters that allow motor trolling with 3 hooks, baits, or lures per angler can be found at http://dnr.wi.gov/topic/fishing/questions/troll.html. All other waters allow motor trolling with 1 hook, bait or lure per angler, and no more than 2 hooks, baits, or lures per boat.
Catfish
Season Dates: Open All Year. No minimum length limit and the daily bag limit is 10.
Cisco and whitefish
Season Dates: Open All Year. No minimum length limit and the daily bag limit is 10.
Lake sturgeon
Season Dates: Closed. No fishing allowed.
Largemouth and smallmouth bass
Season Dates: June 20, 2026 to March 7, 2027. The minimum length limit is 14" and the daily bag limit is 5.
Muskellunge and hybrids
Season Dates: May 2, 2026 to December 31, 2026 on open water. The minimum length limit is 40" and the daily bag limit is 1.
Northern pike
Season Dates: May 2, 2026 to March 7, 2027. No minimum length limit and the daily bag limit is 5.
Paddlefish
Season Dates: Closed. No fishing allowed.
Panfish
Season Dates: Open All Year. No minimum length limit and the daily bag limit is 25.
Rock, yellow, and white bass
Season Dates: Open All Year. No minimum length limit and the daily bag limit is unlimited.
Rough fish
Season Dates: Open All Year. No minimum length limit and the daily bag limit is unlimited.
Shovelnose sturgeon
Season Dates: Closed. No fishing allowed.
Trout and salmon
See Trout regulations layer.
Urban waters gamefish
This waterbody is not considered an urban water, Urban Waters Gamefish regulations do not apply.
Walleye, sauger, and hybrids
Season Dates: May 2, 2026 to March 7, 2027. The minimum length is 15", but walleye, sauger, and hybrids from 20" to 24" may not be kept, and only 1 fish over 24" is allowed. The daily bag limit is 3.
Regulations can change. The official DNR page controls; verify seasons, boundaries, bag limits, and emergency rules before fishing.
353surface acres
21max depth feet
1public access points
45.8373, -88.6775latitude, longitude
Access
Public access points
Boat launchLong Lake Access45.84930, -88.66636Managed by TOWNSHIPTOWN OF LONG LAKERamp surface: GravelADA-accessible feature: NoVerified 2026-07-12
Nearby
Trip-planning places
No nearby trip-planning places yet
Fishery
Notable species
Northern PikePanfishLargemouth Bass
Depth FAQ
How deep is Long Lake?
Long Lake is 21 feet deep at its deepest point, according to Wisconsin DNR records.
Is there a free depth map of Long Lake?
Yes. LakeList publishes a free interactive depth contour map of Long Lake at a typical 5-foot interval, with an optional 3D underwater view, derived from LakeList depth model survey data.
Where does the Long 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 Pagesname, coordinates, county, source identifiers
LakeList record updated 2026-07-12
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