Mille Lacs Lake
Mille Lacs Lake in Aitkin County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 10 ft visibility. Maximum depth: 42 ft. Surface area: 128250.02 acres.
- Clarity
- 10 ft
- Max depth
- 42 ft
- Area
- 128,250 acres
- Trend
- ↓ Declining
- Public access
- Yes
- Ice-out
- Apr 25
- Open water
- 222 days
Next lake in Aitkin County
Why Mille Lacs Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Mille Lacs Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Mille Lacs Lake is a 128,250-acre lake in Aitkin County, Minnesota with a maximum depth of 42 feet (29-foot average). Overall water quality is declining over recent sampling years. The lake supports 21 documented fish species including black bullhead, black crappie, and bluegill. Public access is available.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-13. Grade methodology: LakeGrade methodology.
Watch Mille Lacs Lake water quality
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Mille Lacs Lake Water Quality Report Card (2026)
A printable one-page report card for Mille Lacs Lake: grade, clarity, phosphorus, algae, multi-year trend, depth, and fish — with sources.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Mille Lacs Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 10 ft. Trophic State Index: 44.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 44 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Mille Lacs Lake
Compare lakeside cabins, hotels, and vacation rentals near Mille Lacs Lake in Aitkin County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Mille Lacs Lake
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Planning a trip? Cabins and lodging at Mille Lacs Lake → · more Minnesota lake trips
Current Conditions
USGS snapshot Jul 6, 2026, 4:15 AM from gauge 05284000 (Mille Lacs Lake Nr Garrison, MN). Station page ↗ — a live reading replaces this snapshot when the gauge responds. Missing live data is not an all-clear.
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Mille Lacs Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was moderate (30,479 cells/mL) on October 11, 2025.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 42 ft |
| Average Depth | 28.5 ft |
| Surface Area | 128,250 acres |
| Shoreline Length | 105.5 mi |
| Littoral Zone | 26% |
| Public Access | Yes |
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Mille Lacs Lake
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
DNR Fisheries Survey Summary
36 surveys on file from MN DNR Fisheries. Most recent: 2024-09-01 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Yellow Perch | 219.50 | 0.23 lb |
| Spottail Shiner | 73.62 | 0.02 lb |
| Walleye | 69.99 | 1.23 lb |
| Tullibee (Cisco) | 17.45 | 0.62 lb |
| Smallmouth Bass | 16.43 | 1.74 lb |
| Bluntnose Minnow | 13.53 | 0.01 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.
Yellow Perch
Spottail Shiner
Walleye
Tullibee (Cisco)
From the 2024-09-01 survey
Sampling Programs Mille Lacs Lake is one of ten lakes in Minnesota's Large Lake Program. These lakes have annual sampling of the fish populations, and frequent creel surveys. Specific to Mille Lacs Lake, sampling programs focusing on Walleye, Yellow Perch, Smallmouth Bass, and Northern Pike are conducted annually.…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Mille Lacs Lake. 5 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — Mille LacsFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Mille Lacs (0134)Aquatic Plant Report · MN DNR LakeFinder
- —Aquatic Plant Report — Mille Lacs (0337)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — Mille LacsFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — Mille LacsPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.183 m/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (123 observations).
Estimated open water season: 222 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2024-03-16 (2024) | 2013-05-16 (2013) |
| Ice-In | 1996-11-19 (1996) | 2001-12-22 (2001) |
Most recent ice-out: 2025-04-18
Graded lakes near Mille Lacs Lake
Mille Lacs Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Aitkin County
Frequently asked questions about Mille Lacs Lake
What is the water quality grade for Mille Lacs Lake?
- Mille Lacs Lake in Aitkin County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 10 ft visibility. Maximum depth: 42 ft. Surface area: 128250.02 acres.
Is Mille Lacs Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Mille Lacs Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is Mille Lacs Lake?
- Mille Lacs Lake has a maximum depth of 42 feet and an average depth of 28.5 feet. The lake covers 128250.02 acres.
What fish are in Mille Lacs Lake?
- Fish species found in Mille Lacs Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, burbot, common carp, green sunfish, hybrid sunfish, largemouth bass, muskellunge, northern pike, pumpkinseed, rock bass, shorthead redhorse, smallmouth bass, tullibee (cisco), walleye, white sucker, yellow bullhead, yellow perch. Mille Lacs Lake is located in Aitkin County, Minnesota.
When does Mille Lacs Lake thaw?
- Mille Lacs Lake typically has ice-out around Apr 25. Ice typically forms around Dec 3. The open water season is approximately 222 days.
What is the water level at Mille Lacs Lake?
- The USGS snapshot on this page for Mille Lacs Lake is 10.99 ft of gage height, recorded Jul 6, 2026, 4:15 AM at gauge 05284000. Current Conditions hydrates a live NWIS reading from that same station when the gauge responds. A missed live fetch is not an all-clear.
Does Mille Lacs Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Mille Lacs Lake (clouds, ice, or an off-season gap). The most recent reading was moderate (30,479 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
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Where this data comes from
65 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA65 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (2)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate