Stewart Lake
Stewart Lake in Lake County, Minnesota has a water quality grade of A (Excellent). Water clarity: 10 ft visibility. Phosphorus: 12 µg/L. Chlorophyll-a (algae): 4 µg/L. Maximum depth: 20 ft. Surface area: 237.72 acres.
- Clarity
- 10 ft
- Typical in August
- 70°F
- Max depth
- 20 ft
- Area
- 238 acres
- Type
- Mesotrophic
- Trend
- ↓ Declining
- Public access
- Yes
Next lake in Lake County
Stewart Lake is a 238-acre mesotrophic lake in Lake County, Minnesota with a maximum depth of 20 feet (6-foot average). Water quality is graded A based on 2 sampling years through 2025. 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. Grade methodology: LakeGrade methodology.
Watch Stewart Lake water quality
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Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A (Excellent)
Good clarity, visible to about 10 ft. Phosphorus level: 12 µg/L. Chlorophyll-a: 4 µg/L. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10 ft | Not graded |
| Phosphorus | 12 µg/L | Good |
| Chlorophyll-a (Algae) | 4 µg/L | Good |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay 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.
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Water Temperature
Stewart Lake typically sits around 70°F at the surface in August. 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.
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 →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 20 ft |
| Average Depth | 6.4 ft |
| Surface Area | 238 acres |
| Shoreline Length | 4.9 mi |
| Littoral Zone | 100% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Stewart LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Stewart Lake
DNR Fisheries Survey Summary
13 surveys on file from MN DNR Fisheries. Most recent: 2022-06-16 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Yellow Perch | 20.01 | 0.22 lb |
| Pumpkinseed | 15.86 | 0.18 lb |
| Bluegill | 7.64 | 0.23 lb |
| Hybrid Sunfish | 6.33 | 0.17 lb |
| Walleye | 5.47 | 1.98 lb |
| Northern Pike | 4.78 | 1.99 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
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
Water Quality Trend: ↓ Declining
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.069 m/yr | 6 |
County Ranking
Ranked #8 of 35 lakes in Lake County
Nearby Lakes in Lake County
Frequently asked questions about Stewart Lake
What is the water quality grade for Stewart Lake?
- Stewart Lake in Lake County, Minnesota has a water quality grade of A (Excellent). 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?
- Excellent for swimming, crystal clear water with minimal algae. Stewart Lake has a water quality grade of A (Excellent). Algae concentration (chlorophyll-a) is 4 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Stewart Lake?
- Stewart Lake typically sits around 70°F at the surface in August, 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.
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.
Explore Stewart Lake across LakeGrade
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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Moderate nutrients, good water quality
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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)
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
Named boat-access points from the USGS National Boat Ramps inventory