Flat Rock Impoundment
depth
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Depth scale
Survey readout
Flat Rock Impoundment is mapped to a depth of 3 ft on the Michigan DNR survey and covers about 163 acres in Wayne County, Michigan.
Measured from the Michigan DNR inland-lake contour survey.
- Deepest mapped contour
- 3 ft
- Mean depth
- 1.1 ft · estimated
- Surface area
- 163 acres
- Estimated volume
- 185 acre-ft · 60M gal
- Shoreline
- 7.13 mi · irregular
- Aquatic vegetation
- 48% of surface · NDVI estimate
- Public access
- No public DNR launch identified
Additional depth details2 contours
- Contour depths
- 0–3 ft
- Recorded point soundings
- 3 ft
100% of the surface sits over water shallower than 10 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 Depth, area and volume are estimated from the interpolated survey surface — historical reference, not measurement.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
- 42.10672, -83.31093
- MI DNR lake ID
- L48417
- Basemap
- USDA NAIP · public domain
- Model size
- 2.5 MB
Paddling
Paddling Index methodology v1.0 · calculated 2026-08-21Flat Rock Impoundment has a mixed natural and developed setting, well sheltered geometry, substantial nearby higher-volume roads. 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 | Mixed | 8.5 of 35 | 47% natural land cover within 150 m of shore (21% forest, 25% wetland; 46% developed) |
| Geometric wind exposure | Excellent | 25.4 of 29 | mean fetch 597 m · 30% of sampled water within 500 m of shelter · short fetch in most directions |
| 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 | Modest | 0.9 of 18 | substantial nearby higher-volume roads · 117 MDOT-classified segments within 1.2 km, peak 16,977 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
- High — approximately 48% 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
- Moderate — 21% forest and 25% wetland cover within 150 m of shore
Compare Michigan lakes by Paddling Index →
Fish you might catch
from angler catches11 species with recent evidence in this lake — sized relative to each other. Illustrations are AI-generated representative adults in everyday colours, not photographs (provenance).
Bowfin
Rainbow Trout
Redhorse Sucker
Largemouth Bass
White Sucker
Northern Hognose Sucker
Quillback
Smallmouth Bass
Gizzard Shad
White Bass
CrappieFishing rules for this lake Beta
Size and daily limits for the 11 species found here — 10 open to harvest, 1 with a special rule or closed season.
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 · 2007–2025Trophy-size fish anglers caught here and registered with the DNR — what people have actually caught, distinct from what a survey netted or the state stocked below.
Catch details by species11 species
Biggest on record
Bait: artificial lure (10) · live bait (3) · flies (2)
Method: spincasting (13) · still fishing (3)
At the lake
community-mapped amenities · straight-line distanceBait & tackle nearby
licensed retail bait dealers · straight-line distanceFlat Rock Impoundment — common questions
How deep is Flat Rock Impoundment?
The deepest contour on the Michigan DNR bathymetric survey of Flat Rock Impoundment is 3 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 Flat Rock Impoundment?
Flat Rock Impoundment covers about 163 acres in Wayne County, Michigan.
What is the average depth of Flat Rock Impoundment?
The estimated mean depth of Flat Rock Impoundment is 1.1 ft, calculated from the survey contours.
What fish are in Flat Rock Impoundment?
Species with survey, catch or recent-stocking evidence include largemouth bass, rainbow trout, smallmouth bass, bowfin, crappie, white bass. The page lists all 11 species and the evidence behind each.
Is there public access to Flat Rock Impoundment?
No public launch for Flat Rock Impoundment 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.
