Union Lake
depth
Get directions
Depth scale
Survey readout
Union Lake is mapped to a depth of 110 ft on the Michigan DNR survey and covers about 469 acres in Oakland County, Michigan.
Measured from the Michigan DNR inland-lake contour survey.
- Deepest mapped contour
- 110 ft
- Mean depth
- 29.1 ft · estimated
- Surface area
- 469 acres
- Estimated volume
- 13,634 acre-ft · 4,443M gal
- Shoreline
- 5.17 mi · irregular
- Aquatic vegetation
- 1% of surface · NDVI estimate
- Public access
- Boat Launch
Additional depth details17 contours
- Contour depths
- 0–110 ft
- Recorded point soundings
- 110 ft, 68 ft, 65 ft, 58 ft
36.1% of the surface sits over water shallower than 10 ft; 50.3% 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 Depth, area and volume are estimated from the interpolated survey surface — historical reference, not measurement.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.
⚠ Not for navigationSpot an error? Send a correction
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
- 42.60621, -83.43489
- MI DNR lake ID
- L4899
- Vertical exaggeration
- 1.4×
- Basemap
- USDA NAIP · public domain
- Model size
- 2.6 MB
Paddling
Paddling Index methodology v1.0 · calculated 2026-08-21Union Lake has a substantially developed setting, moderate open-water exposure, 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 | Modest | 0.6 of 30 | 4% natural land cover within 150 m of shore (1% forest, 3% wetland; 88% developed) |
| Geometric wind exposure | Good | 11.3 of 25 | mean fetch 1,513 m · 0% of sampled water within 500 m of shelter · moderate open-water fetch |
| Watercraft controls | None identified | 7.5 of 15 | No special watercraft restriction identified in the current DNR source. Motors permitted, subject to general law. |
| Public access | Excellent | 15.0 of 15 | 2 sites with DNR boating-facility records · carry-in launch · 2 ramp lanes · 21 trailer spaces |
| Road isolation | Modest | 0.8 of 15 | substantial nearby higher-volume roads · 203 MDOT-classified segments within 1.2 km, peak 31,240 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 1% 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
- Limited — 1% forest and 3% wetland cover within 150 m of shore
Compare Michigan lakes by Paddling Index →
Fish you might catch
from angler catches, DNR surveys & active stocking21 species with recent evidence in this lake — sized relative to each other. Illustrations are AI-generated representative adults in everyday colours, not photographs (provenance).
Longnose Gar
Northern Pike
Bowfin
Channel Catfish
Walleye
Largemouth Bass
White Sucker
Smallmouth Bass
Cisco
Brown Bullhead
Black Bullhead
Black CrappieCrappie
Yellow Bullhead
Redear Sunfish
Yellow Perch
Bluegill
Rock Bass
Pumpkinseed
Green Sunfish
Golden ShinerHistorically stocked, no recent evidence: Rainbow Trout (last planted 1990), Splake (last planted 1990), Lake Trout (last planted 1989), Brown Trout (last planted 1984) — not shown above.
Fishing rules for this lake Beta
Size and daily limits for the 21 species found here — 21 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 · 1994–2025Trophy-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: live bait (8) · minnow (7) · worm (5)
Method: spincasting (24) · drift fishing (15) · ice fishing (13) · still fishing (5)
Fishery
Gamefish Walleye 172 · Largemouth Bass 156 · Smallmouth Bass 109 · Bowfin 77
Panfish Bluegill 1,615 · Rock Bass 612 · Black Crappie 236
All survey species16 species
Gamefish
Panfish
Bullhead & catfish
Forage & nongame
DNR stocking
state stocking record · 1979–2023Fish the Michigan DNR has planted in this lake — what was added, distinct from what a survey netted above.
Complete stocking history5 older species
Non-native species records
2 recordsMussels & snails
- Zebra Mussel
Plants & algae
- Purple Loosestrife
What does non-native mean?
USGS records identify non-native species that have been documented for this lake or its shoreline. Non-native does not necessarily mean invasive, and historical records do not confirm current presence.
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 distanceUnion Lake — common questions
How deep is Union Lake?
The deepest contour on the Michigan DNR bathymetric survey of Union Lake is 110 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 Union Lake?
Union Lake covers about 469 acres in Oakland County, Michigan.
What is the average depth of Union Lake?
The estimated mean depth of Union Lake is 29.1 ft, calculated from the survey contours.
What fish are in Union Lake?
Species with survey, catch or recent-stocking evidence include channel catfish, largemouth bass, northern pike, smallmouth bass, walleye, black bullhead. The page lists all 21 species and the evidence behind each.
Is there public access to Union Lake?
Yes. The Michigan DNR boat-launch data identifies 2 public access sites on Union Lake, including Union Lake.
