Little Portage Lake
depth
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Depth scale
Survey readout
Little Portage Lake is mapped to a depth of 42 ft on the Michigan DNR survey and covers about 96 acres in Washtenaw County, Michigan.
Measured from the Michigan DNR inland-lake contour survey.
- Deepest sounding
- 42 ft
- Mean depth
- 14.7 ft · estimated
- Surface area
- 96 acres
- Estimated volume
- 1,401 acre-ft · 457M gal
- Shoreline
- 2.47 mi · irregular
- Aquatic vegetation
- 11% of surface · NDVI estimate
- Trophic state
- Mesotrophic · measured 2012 · details
- Public access
- No public DNR launch identified
Additional depth details11 contours
- Contour depths
- 0–42 ft
- Recorded point soundings
- 42 ft, 42 ft, 14 ft, 12 ft
44.3% of the surface sits over water shallower than 10 ft; 36.7% 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 Depth, area and volume are estimated from the interpolated survey surface — historical reference, not measurement.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. Color shows surveyed depth; dark lines are the survey's own isobaths.
- Coordinates
- 42.41392, -83.93135
- MI DNR lake ID
- L15682
- Vertical exaggeration
- 2.25×
- Basemap
- USDA NAIP · public domain
- Model size
- 2.3 MB
Lake productivity & trophic state
Measured 2012Classification: Mesotrophic. Moderate nutrient levels and biological productivity. Based on measurements recorded in 2012 (chlorophyll-a 4.6 µg/L).
Trophic state describes how biologically productive a lake is, based on indicators such as nutrients, algae and water clarity. It is not a swimming-safety or overall water-quality rating.
What do the categories mean?
- Oligotrophic≤ 2 µg/L · lower nutrient and algae levels, often clearer water and lower biological productivity.
- Mesotrophic · this lake2–7 µg/L · moderate nutrient levels and biological productivity.
- Eutrophic7–30 µg/L · higher nutrient levels and biological productivity, often with more algae or aquatic plant growth.
- Hypereutrophic> 30 µg/L · very high nutrient levels and biological productivity, with a greater potential for heavy algae growth and low water clarity.
Bands are summer (June–August) mean chlorophyll-a, the green pigment in algae, at the EPA 2012 National Lakes Assessment thresholds. Trophic condition can change over time and by measurement method. Source: Midwest Glacial Lakes Partnership Conservation Planner; chlorophyll-a measurements from LAGOS-US LIMNO.
Watercraft rules
county-enforced local controls · MI DNROfficial rule details1 rule
Paddling
Paddling Index methodology v1.0 · calculated 2026-09-23Little Portage Lake has a heavily wooded and largely undeveloped setting, generally sheltered geometry, nearby higher-volume roads. Watercraft controls: Slow-no-wake zones.
Why this score?5 components
Included in the index
| Component | Rating | Points of weight | Measurement |
|---|---|---|---|
| Natural setting | Excellent | 28.7 of 35 | 80% natural land cover within 150 m of shore (6% forest, 74% wetland; 10% developed) |
| Geometric wind exposure | Very Good | 23.4 of 29 | mean fetch 666 m · 4% of sampled water within 500 m of shelter · generally short fetch |
| Watercraft controls | Slow-no-wake zones | 12.0 of 18 | Slow — no wake — designated zones only |
| 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 | Mixed | 5.6 of 18 | nearby higher-volume roads · 19 MDOT-classified segments within 1.2 km, peak 11,184 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 11% 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 — 6% forest and 74% wetland cover within 150 m of shore
Compare Michigan lakes by Paddling Index →
Fish you might catch
from angler catches3 species with recent evidence in this lake — sized relative to each other. Illustrations are AI-generated representative adults in everyday colors, not photographs (provenance).
About these fish → the Fish of Michigan guide
Fishing rules for this lake Beta
Size and daily limits for the 3 species found here — 3 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 2026-09-15. Regulations can change — Michigan DNR rules are the controlling source; verify current regulations before fishing. Official regulations
Notable catches
Master Angler program · 2018–2025Trophy-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.
Biggest on record
Bait: artificial lure (2) · live bait (2)
Method: spincasting (4) · still fishing (1) · ice fishing (1)
Non-native species records
1 recordPlants & algae
- Brittle Waternymph
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 distanceLittle Portage Lake — common questions
How deep is Little Portage Lake?
The deepest contour on the Michigan DNR bathymetric survey of Little Portage Lake is 42 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 Little Portage Lake?
Little Portage Lake covers about 96 acres in Washtenaw County, Michigan.
What is the average depth of Little Portage Lake?
The estimated mean depth of Little Portage Lake is 14.7 ft, calculated from the survey contours.
What fish are in Little Portage Lake?
Species with survey, catch or recent-stocking evidence include bluegill, crappie, rock bass. The page shows the evidence behind each.
Is there public access to Little Portage Lake?
No public launch for Little Portage 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.
