Trout Lake
Cook County, Minnesota259 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Trout Lake. Here is what has been measured.
- Oligotrophic
- Impaired · Mercury
- spiny waterflea
- 77 ft max depth
- Public access
Trout Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 18.4 ft visibility. Phosphorus: 9 µg/L. Chlorophyll-a (algae): 1.3 µg/L. Maximum depth: 77 ft. Surface area: 258.91 acres.
Minnesota DNR's Targeted Survey on August 18, 2025 caught 0.10 brook trout per fyke net at Trout Lake. DNR survey details →
Trout Lake is a 259-acre cold, clear oligotrophic lake in Cook County, Minnesota with a maximum depth of 77 feet. Overall water quality is declining over recent sampling years. The lake supports 6 documented fish species including brook trout, lake trout, and rainbow smelt. Public access is available. Compared to the 43 other monitored lakes in Cook County, Trout Lake ranks #6 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-07. Methodology: how these readings are compared.
Trout Lake covers about 260 acres in Cook County. The median ice-out date is May 6, which is when the open-water season begins. If you are planning to stay, you can search lake houses and cabins around Trout Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Trout Lake is good for
From access and monitoring records, not editorial picks.
- Clear water18.4 ft of visibility
- Fishing6 species recorded
- Ice seasonIce-out around May 6
- Deep water77 ft surveyed max depth
Swimming conditions
Readings onlyLow algae
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Trout Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Trout Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Trout Lake
These are the measurements Minnesota PCA publishes for Trout Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 18.4 ft down. Phosphorus 9 µg/L. Chlorophyll-a 1.3 µg/L. TSI 35.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 18.4ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 9µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 1.3µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 35 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Trout Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Trout Lake typically sits around 49°F at the surface in October. Summer average is about 53°F. Usually warmest in Aug (about 55°F) and coldest in Mar (about 36°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (36°F) to its warmest (55°F).
Typical surface water temperature by month, from 1,423 field readings (2010–2025) via the EPA Water Quality Portal. See the full Trout Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Trout Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (539,511 cells/mL) on June 1, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Minnesota DNR's Targeted Survey on August 18, 2025 caught 0.10 brook trout per fyke net at Trout Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Trout Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
20 surveys on file from MN DNR Fisheries. Most recent: 2025-08-18 (Targeted Survey).
20 surveys on file · most recent 2025-08-18 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 15.64 | 4–9 in 2025-07-28 | 0.13 lb |
| Golden Shiner | 2.98 | 4–5 in 2025-07-28 | 0.07 lb |
| Lake Trout | 2.76 | 4–35 in 2023-07-24 | 1.1 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
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
Golden Shiner
Lake Trout
From the 2025-08-18 survey
A targeted survey of nearshore fish species in Trout Lake was conducted on August 18- 20, 2025, by Lake Biological Monitoring and Assessment Program staff. Ten nearshore sampling sites were evenly spaced around the lake, and each were sampled by backpack electrofishing, mini-fyke nets, and seining with a 15-foot…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Trout Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — TroutFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Trout (1591)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — TroutFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — TroutPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
77 ft
Surface area
259 acres
Shoreline
3.3 mi
Littoral zone
23%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,657 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Trout Lake
Compare lakeside cabins, hotels, and vacation rentals near Trout Lake in Cook 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 Trout Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Minnesota’s top lakes →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Trout 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.
Water Quality Trend: Worsening
Based on 5 years of monitoring (2020–2025).
Water clarity
Worsening5 years
Phosphorus
Worsening+0.77 µg/L/yr4 years
Chlorophyll-a
Improving-0.05 µg/L/yr4 years
Ice season
Typical ice-out
May 6
Earliest Apr 8, 2012 · Latest May 21, 2014
Most recent ice-out
Apr 26
2017
8 observations · Minnesota PCA ice records
EPA Impairment Status
Trout Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN16-0049-00 · Official waterbody report
Nearby Lakes in Cook County
Frequently asked questions about Trout Lake
Where is Trout Lake?
- Trout Lake is a lake in Cook County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Trout Lake?
- Trout Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 18.4 ft visibility. Phosphorus: 9 µg/L. Chlorophyll-a (algae): 1.3 µg/L. Maximum depth: 77 ft. Surface area: 258.91 acres.
Is Trout Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Trout Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
What is the water temperature of Trout Lake?
- Trout Lake typically sits around 49°F at the surface in October, from 1,423 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Trout Lake?
- Trout Lake has a maximum depth of 77 feet. The lake covers 258.91 acres.
What fish are in Trout Lake?
- Fish species found in Trout Lake include brook trout, lake trout, rainbow smelt, rainbow trout, white sucker, yellow perch. Trout Lake is located in Cook County, Minnesota.
What did the DNR fisheries survey find at Trout Lake?
- Minnesota DNR's Targeted Survey on August 18, 2025 caught 0.10 brook trout per fyke net at Trout Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Trout Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Trout Lake thaw?
- Trout Lake typically has ice-out around May 6.
Does Trout Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Trout Lake (clouds, ice, or an off-season gap). The most recent reading was high (539,511 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Can I fish at Trout Lake?
- Public access to Trout Lake is listed as yes on the lake record. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Trout Lake across LakeQuality
6.2 mi away · 50 ft
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Cook County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Lake Superior Basin (MN+WI), ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
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Other Lakes in Minnesota
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Where this data comes from
79 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA79 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 2130 B ~ Nephelometric Method
- 2120 B ~ Color in Water by Visual Comparison
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate