Stewart Lake
Lake County, Minnesota238 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Stewart Lake. Here is what has been measured.
- Mesotrophic
- 20 ft max depth
- Public access
- Limited data
Stewart Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 10 ft visibility. Phosphorus: 12 µg/L. Chlorophyll-a (algae): 4 µg/L. Maximum depth: 20 ft. Surface area: 237.72 acres.
Minnesota DNR's Targeted Survey on June 16, 2022 caught 8.94 walleye per hour of electrofishing at Stewart Lake. Length samples in the latest survey that recorded them ran 7–15 inches. DNR survey details →
Stewart Lake is a 238-acre mesotrophic lake in Lake County, Minnesota with a maximum depth of 20 feet (6-foot average). Overall water quality is declining over recent sampling years. The lake supports 7 documented fish species including black crappie, bluegill, and hybrid sunfish. Public access is available with 1 public boat landing. Compared to the 34 other monitored lakes in Lake County, Stewart Lake ranks #8 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-08. Methodology: how these readings are compared.
What Stewart Lake is good for
From access and monitoring records, not editorial picks.
- Clear water10 ft of visibility
- Boat launch1 documented ramp
- Fishing7 species recorded
Swimming conditions
Readings onlyLimited data
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. Check local advisories before you swim.
Whether Stewart 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 Stewart Lake
These are the measurements Minnesota PCA publishes for Stewart Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 10 ft. Phosphorus 12 µg/L. Chlorophyll-a 4 µg/L. TSI 43.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 10ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 12µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 4µg/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. | 43 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Stewart Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Stewart Lake typically sits around 65°F at the surface in September. Summer average is about 68°F. Usually warmest in Jul (about 72°F) and coldest in May (about 53°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (53°F) to its warmest (72°F).
Typical surface water temperature by month, from 38 field readings (2019–2024) via the EPA Water Quality Portal. See the full Stewart Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on June 16, 2022 caught 8.94 walleye per hour of electrofishing at Stewart Lake. Length samples in the latest survey that recorded them ran 7–15 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Stewart Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
13 surveys on file from MN DNR Fisheries. Most recent: 2022-06-16 (Targeted Survey).
13 surveys on file · most recent 2022-06-16 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 20.01 | 4–10 in 2020-08-03 | 0.22 lb |
| Pumpkinseed | 15.86 | 3–8 in 2014-07-28 | 0.18 lb |
| Bluegill | 7.64 | 4–8 in 2020-08-03 | 0.23 lb |
| Hybrid Sunfish | 6.33 | 2–8 in 2020-08-03 | 0.17 lb |
| Walleye | 5.47 | 7–15 in 2022-06-16 | 1.98 lb |
| Northern Pike | 4.78 | 9–40 in 2020-08-03 | 1.99 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
Pumpkinseed
Bluegill
Hybrid Sunfish
From the 2022-06-16 survey
A night electrofishing survey was completed on Stewart Lake on June 16th 2022 to determine if Largemouth Bass are present. No Largemouth Bass were sampled despite targeting a time and location when we would expect to catch bass. Other fish sampled during the survey included a small number of Walleye ranging in length…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Stewart Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — StewartFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Stewart (0857)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — StewartPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
20 ft
Average depth
6.4 ft
Surface area
238 acres
Shoreline
4.9 mi
Littoral zone
100%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
3 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,627 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Stewart LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Stewart Lake
Compare lakeside cabins, hotels, and vacation rentals near Stewart Lake in Lake 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 Stewart Lake
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Fish Species
Click a species to see every lake where it is documented.
Fishing Stewart Lake
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Nearby Lakes in Lake County
Frequently asked questions about Stewart Lake
Where is Stewart Lake?
- Stewart Lake is a lake in Lake County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Stewart Lake?
- Stewart Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 10 ft visibility. Phosphorus: 12 µg/L. Chlorophyll-a (algae): 4 µg/L. Maximum depth: 20 ft. Surface area: 237.72 acres.
Is Stewart Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Stewart Lake?
- Stewart Lake typically sits around 65°F at the surface in September, from 38 EPA Water Quality Portal field readings (2019–2024). That is a typical value for the month, not a live reading.
How deep is Stewart Lake?
- Stewart Lake has a maximum depth of 20 feet and an average depth of 6.4 feet. The lake covers 237.72 acres.
What fish are in Stewart Lake?
- Fish species found in Stewart Lake include black crappie, bluegill, hybrid sunfish, northern pike, walleye, white sucker, yellow perch. Stewart Lake is located in Lake County, Minnesota.
What did the DNR fisheries survey find at Stewart Lake?
- Minnesota DNR's Targeted Survey on June 16, 2022 caught 8.94 walleye per hour of electrofishing at Stewart Lake. Length samples in the latest survey that recorded them ran 7–15 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Stewart Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Stewart Lake?
- Stewart Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Stewart Lake. Public access is listed as yes.
Can I fish at Stewart Lake?
- Stewart Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. 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 Stewart Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
13.8 mi away · 60 ft
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Fish species and best lakes in Lake County
Species activity outlook by water temperature and season
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Where this data comes from
76 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
MNPCA76 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Phosphorus by Colorimetry
- 2130 B ~ Nephelometric Method
- 2120 B ~ Color in Water by Visual Comparison
Monitoring station identifiers (2)
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory