Grassy Lake
depth
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Depth scale
Survey readout
Grassy Lake is mapped to a depth of 30 ft on the Michigan DNR survey and covers about 191 acres in Schoolcraft County, Michigan.
Measured from the Michigan DNR inland-lake contour survey (depths read from the survey's isobath field; this lake's summary-depth column is blank in the source).
- Deepest mapped contour
- 30 ft
- Mean depth
- 9.9 ft · estimated
- Surface area
- 191 acres
- Estimated volume
- 1,886 acre-ft · 615M gal
- Shoreline
- 3.03 mi · irregular
- Aquatic vegetation
- 4% of surface · NDVI estimate
- Public access
- No public DNR launch identified
Additional depth details6 contours
- Contour depths
- 0–30 ft
- Recorded point soundings
- 30 ft
57.8% of the surface sits over water shallower than 10 ft; 14.1% is deeper than 20 ft. Depth, area and volume are estimated from the interpolated survey surface — historical reference, not measurement.
Compare with another lakeProvenance
Sources: MI DNR inland lake contours, USGS 3DEP, USDA NAIP (public domain), OpenStreetMap (ODbL), MI DNR Boat Launches.
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Map details & sources5 sources
All layers registered to one bounding box; positions in WGS 84.
Survey-derived depth contours drape over USGS 3DEP elevation, with a USDA NAIP aerial basemap and OpenStreetMap shoreline. Colour shows surveyed depth; dark lines are the survey's own isobaths.
- Coordinates
- 46.22241, -86.58191
- MI DNR lake ID
- L32234
- Vertical exaggeration
- 2.66×
- Basemap
- USDA NAIP · public domain
- Model size
- 2.4 MB
Paddling
Paddling Index methodology v1.0 · calculated 2026-08-21Grassy Lake has a heavily wooded and largely undeveloped setting, generally sheltered geometry, limited nearby major-road exposure. No special watercraft restriction is identified in the current source.
Why this score?5 components
Included in the index
| Component | Rating | Points of weight | Measurement |
|---|---|---|---|
| Natural setting | Excellent | 31.4 of 35 | 88% natural land cover within 150 m of shore (56% forest, 32% wetland; 8% developed) |
| Geometric wind exposure | Very Good | 18.5 of 29 | mean fetch 985 m · 0% of sampled water within 500 m of shelter · generally short fetch |
| Watercraft controls | None identified | 8.8 of 18 | No special watercraft restriction identified in the current DNR source. Motors permitted, subject to general law. |
| Public access | Not listed | — | No DNR-listed access site. Township, county and road-end launches are not in this source, so this is not evidence that access is poor — the component is excluded and the remaining weights are renormalized. |
| Road isolation | Very Good | 11.9 of 18 | limited nearby major-road exposure · 5 MDOT-classified segments within 1.2 km, peak 161 vehicles/day |
Additional paddling considerations
These describe the lake but are not part of the v1 Paddling Index and do not change the number above.
- Wake sensitivity
- Low — wide enough that wakes disperse over most of the lake
- Aquatic vegetation
- Low — approximately 4% mapped coverage · NAIP aerial imagery (NDVI)
- Observed motorized activity
- Unknown — No lake-level measurement of boat traffic is available. Legal permission to operate motors is not evidence of use.
- Wildlife habitat potential
- High — 56% forest and 32% wetland cover within 150 m of shore
Compare Michigan lakes by Paddling Index →
Fish you might catch
from angler catches, DNR surveys & active stocking6 species with recent evidence in this lake — sized relative to each other. Illustrations are AI-generated representative adults in everyday colours, not photographs (provenance).
Muskellunge
Northern Pike
Walleye
Largemouth Bass
Smallmouth Bass
BluegillFishing rules for this lake Beta
Size and daily limits for the 6 species found here — 6 open to harvest.
These are hook-and-line size, daily limit and season rules. Gear, spearing and bow fishing, spawning closures and rod limits are set by other Fisheries Orders and are not shown here.
From FO-206.26 (eff. 2026-04-01) / FO-215.23A (eff. 2023-09-15) / FO-254.25 (eff. 2025-10-10), checked against the 2026 Michigan Fishing Regulations digest · verified 2026-08-24. Regulations can change — Michigan DNR rules are the controlling source; verify current regulations before fishing. Official regulations
Notable catches
Master Angler program · 2015–2024Master Angler catches recorded on this lake — too few to show a pattern, so they are listed individually.
Fishery
surveyed 2016 · DNR SFR 2018-260Forage & nongame
DNR stocking
state stocking record · 1980–1984Fish the Michigan DNR has planted in this lake — what was added, distinct from what a survey netted above.
No stockings recorded since 1984 — shown as history.
Non-native species records
No non-native species recorded in the available dataset. This does not confirm that no non-native species are present.
Source: Midwest Glacial Lakes Partnership Conservation Planner; underlying nonindigenous species records from the USGS Nonindigenous Aquatic Species database.
At the lake
community-mapped amenities · straight-line distanceBait & tackle nearby
licensed retail bait dealers · straight-line distanceGrassy Lake — common questions
How deep is Grassy Lake?
The deepest contour on the Michigan DNR bathymetric survey of Grassy Lake is 30 ft. That is the deepest depth the historical survey map records, which may differ from the deepest point of the lake itself.
How big is Grassy Lake?
Grassy Lake covers about 191 acres in Schoolcraft County, Michigan.
What is the average depth of Grassy Lake?
The estimated mean depth of Grassy Lake is 9.9 ft, calculated from the survey contours.
What fish are in Grassy Lake?
Species with survey, catch or recent-stocking evidence include largemouth bass, muskellunge, northern pike, smallmouth bass, walleye, bluegill. The page shows the evidence behind each.
Is there public access to Grassy Lake?
No public launch for Grassy Lake appears in the Michigan DNR access data. That is not the same as the lake being private -- municipal and private ramps are not in that source.
