Shamineau Lake
Morrison County, MinnesotaMesotrophic
Shamineau Lake sits at the top of the Minnesota PCA grading rubric with an A, a mark reached by the cleanest lakes in Minnesota. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.
The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. Shamineau Lake is unusually deep for Minnesota at 52 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. At 1,434 acres, Shamineau Lake is one of the larger lakes in Morrison County, with 10.3 miles of shoreline supporting multiple distinct use patterns. Shamineau Lake ranks 5 of 16 in Morrison County — solidly in the upper half of the local distribution.
Shamineau Lake carries an invasive watermilfoil record — boat-launch decontamination and shoreline care matter more here than at uninfested lakes. Muskie are on the species list at Shamineau Lake, alongside the lake's 18 other documented fish. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been logged at Shamineau Lake more than two dozen times, putting the median around Apr 20 — a useful baseline for tracking climate trends. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-09-15. Grade methodology: LakeGrade methodology.
Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Good clarity, visible to about 12.5 ft. Phosphorus level: 14 µg/L. Trophic State Index: 41.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 12.5 ft | B |
| Phosphorus | 14 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 41 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 52 ft |
| Average Depth | 17 ft |
| Surface Area | 1.4K acres |
| Shoreline Length | 10.3 mi |
| Littoral Zone | 52% |
| Public Access | Yes |
Fish Species
Click a species to see all Minnesota and Wisconsin lakes where it is found.
→ Best fishing times for Shamineau Lake (14-day solunar calendar)
→ Is it safe to eat fish from Shamineau Lake? (mercury & PFAS guide)
→ Shamineau Lake fishing regulations (limits, seasons, special rules)
Invasive Species
Water Quality Trend: → Stable
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.38 m/yr | 5 |
| Phosphorus | ↓ Declining | +0.7 µg/L/yr | 5 |
Ice Season
Historical ice data from Minnesota DNR (76 observations).
Estimated open water season: 225 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2012-03-24 (2012) | 2013-05-14 (2013) |
| Ice-In | 2017-11-21 (2017) | 2015-12-19 (2015) |
Most recent ice-out: 2022-05-04
Location
County Ranking
Ranked #5 of 16 lakes in Morrison County
Nearby Lakes in Morrison County
More Minnesota Lake Rankings
State Parks Near Shamineau Lake
Other Grade A Lakes in Minnesota
Mesotrophic Lakes in Minnesota
DNR Fisheries Survey Summary
24 surveys on file from MN DNR Fisheries. Most recent: 2025-04-15 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluntnose Minnow | 46.33 | — |
| Bluegill | 30.48 | 0.11 lb |
| Muskellunge | 21.13 | 12.63 lb |
| Largemouth Bass | 18.50 | 0.83 lb |
| Spottail Shiner | 14.52 | — |
| Walleye | 10.13 | 1.89 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
Bluegill
Muskellunge
Largemouth Bass
Walleye
From the 2025-04-15 survey
Shamineau Lake (DOW # 49-0127-00; Lake Class 27) is a 1,434-acre lake located near Motley, Minnesota. A Minnesota Department of Natural Resources (MNDNR) owned concrete boat ramp is located on the west shore and a township owned gravel boat ramp is located on the east shore. Shamineau Lake has 10.34 miles of shoreline…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Shamineau Lake. 4 reports on file.
- —Fisheries Lake Survey — ShamineauFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Shamineau (1914)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — ShamineauFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — ShamineauPublic Water Access Sites · MN DNR LakeFinder
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate
Most recent sample: 2024-09-15
Monitoring stations: 2