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Grindstone Lake
Enhanced dataInteractive depth contours
Grindstone LakeSawyer 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 80% of the lake. Small gaps between recordings are smoothly connected; larger unrecorded areas follow the lake's depth model calibrated to the DNR-documented 60-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 Grindstone Lake.
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Fishing forecast
Best windows for Grindstone 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
Grindstone 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 Grindstone Lake - Deep Hole.
Last sampled Sep 2024
Through 2024, very low algae readings and moderate nutrients in the most recent monitored summers.
Based on July–August volunteer averages from 2021–2024; each value shows its own year.AlgaeChlorophyll-a
2.5 µg/LJul–Aug 2021 avg (2 readings)
Very lowWorsening — up ~34% vs earlier years
NutrientsTotal phosphorus — fuels plant & algae growth
23.5 µg/LJul–Aug 2024 avg (6 readings)
Moderate2021–2024
Moderate phosphorus can support noticeable plant/algae growth.
No recent clarity readings — last measured 2014.
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 |
|---|---|---|---|
| 2024 | — | — | 23.5 µg/L (6) |
| 2023 | — | — | 18.3 µg/L (4) |
| 2022 | — | — | 16.2 µg/L (6) |
| 2021 | — | 2.5 µg/L (2) | 20.6 µg/L (7) |
| 2015 | — | 2.3 µg/L (3) | — |
| 2014 | 17.4 ft (2) | 3.0 µg/L (1) | — |
| 2013 | 20.2 ft (4) | 1.5 µg/L (4) | — |
| 2012 | 17.6 ft (3) | 2.3 µg/L (3) | — |
| 2011 | 15.7 ft (4) | 2.0 µg/L (4) | — |
| 2010 | 20.7 ft (7) | 1.9 µg/L (8) | — |
Latest individual samples: Secchi 13 ft (2014-09-11), chlorophyll-a 4 µg/L (2021-09-15), and total phosphorus 14 µg/L (2024-09-04).
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.
Grindstone Lake - Deep HoleStation 583065
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
Grindstone Lake depth maps
1 converted map sheet. These historical surveys are not for navigation.
Navigable depth map
Grindstone 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 2391200 · 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.
Fishbrain community activity
Recent catch activity
Aggregated public catch activity matched to Grindstone Lake. Exact catch locations and angler details are not shown.
Most reported species in this extract
Smallmouth bass38Yellow perch13Largemouth bass11Walleye11Muskellunge6Northern pike4Brook trout1
Catch analytics
Seasonal fish catch patterns
Pick a species to see when anglers reported it, compare against all fish by month, then scan year-by-year catch volume.
Smallmouth bass by monthMonthly reports tagged as Smallmouth bass.
Jan
Feb
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Apr
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Jul
Aug
Sep
Oct
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Dec
All fish by monthTotal public catch reports across every listed species.
Jan
Feb
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1Jul
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Yearly catch view2026 had the most reported catch activity.
20260 Smallmouth bass1 all fish
Recent catch detailsLatest authorized records; measurements appear only when reported.
- Largemouth bassCommunity report · Jul 3, 202611 in0.9 lb
Catch counts are community reports, not a population survey or a guarantee of current fishing conditions.
View source on Fishbrain3,176surface acres
60max depth feet
2public access points
45.9357, -91.4108latitude, longitude
Access
Public access points
Boat launchGrindstone Lake Access45.92850, -91.39509Managed by TOWNSHIPTOWN OF BASS LAKERamp surface: GravelADA-accessible feature: NoVerified 2026-07-12
Boat launchGrindstone Lake Access45.92065, -91.44391Managed by STATE(DNR)TOWN OF BASS LAKERamp surface: ConcreteADA-accessible feature: NoVerified 2026-07-12
Nearby
Trip-planning places
No nearby trip-planning places yet
Fishery
Notable species
WalleyeMuskyNorthern PikeSmallmouth BassLargemouth BassPanfish
Wisconsin DNR stocking
Fish stocking history
The latest published year is 2024, when 1,201 fish were recorded across 2 entries.
2024
MuskellungeUpper Chippewa River · Large Fingerling
1,00313.5 in average
2024
MuskellungeUpper Chippewa River · Large Fingerling
19812.0 in average
2021
MuskellungeUpper Chippewa River · Large Fingerling
1,77314.0 in average
2017
MuskellungeUpper Chippewa River · Large Fingerling
73611.9 in average
2014
MuskellungeUpper Chippewa River · Large Fingerling
3,10811.0 in average
2011
MuskellungeUpper Chippewa River · Large Fingerling
2,99110.1 in average
Depth FAQ
How deep is Grindstone Lake?
Grindstone Lake is 60 feet deep at its deepest point and averages about 30 feet, according to Wisconsin DNR records.
Is there a free depth map of Grindstone Lake?
Yes. LakeList publishes a free interactive depth contour map of Grindstone 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 Grindstone 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 Mapsname, coordinates, county, source identifiers
LakeList record updated 2026-07-12
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