Sleepy Eye Lake
Brown County, Minnesota241 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Sleepy Eye Lake. Here is what has been measured.
- Eutrophic
- 21 ft max depth
- Public access
Sleepy Eye Lake in Brown County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3.3 ft visibility. Phosphorus: 39.5 µg/L. Chlorophyll-a (algae): 18.7 µg/L. Maximum depth: 21 ft. Surface area: 240.82 acres.
Minnesota DNR's Targeted Survey on August 16, 2021 caught 15.17 walleye per gill net at Sleepy Eye Lake. DNR survey details →
Sleepy Eye Lake is a 241-acre productive, nutrient-rich eutrophic lake in Brown County, Minnesota with a maximum depth of 21 feet (7-foot average). Overall water quality is declining over recent sampling years. The lake supports 10 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 3 other monitored lakes in Brown County, Sleepy Eye Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-10-11. Methodology: how these readings are compared.
What Sleepy Eye Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing10 species recorded
- Ice seasonIce-out around Mar 27
Swimming conditions
Readings onlyAlgae risk
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 Sleepy Eye 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 Sleepy Eye Lake
These are the measurements Minnesota PCA publishes for Sleepy Eye Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 3.3 ft of visibility. Phosphorus 39.5 µg/L. Chlorophyll-a 18.7 µg/L. TSI 59.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 39.5µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 18.7µg/L | Fair GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 59 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Sleepy Eye Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Sleepy Eye Lake typically sits around 52°F at the surface in October. Summer average is about 79°F. Usually warmest in Jul (about 81°F) and coldest in Oct (about 52°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (52°F) to its warmest (81°F).
Typical surface water temperature by month, from 96 field readings (2017–2023) via the EPA Water Quality Portal. See the full Sleepy Eye Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on August 16, 2021 caught 15.17 walleye per gill net at Sleepy Eye Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Sleepy Eye Lake’s water-quality measurements separately, and the water-quality trend over 4 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
18 surveys on file from MN DNR Fisheries. Most recent: 2021-08-16 (Targeted Survey).
18 surveys on file · most recent 2021-08-16 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Black Bullhead | 116.05 | 9–13 in 2021-08-16 | 0.47 lb |
| Bluegill | 31.13 | 3–7 in 2021-08-16 | 0.16 lb |
| White Crappie | 26.64 | 0.32 lb | |
| Yellow Perch | 20.59 | 5–11 in 2021-08-16 | 0.15 lb |
| Black Crappie | 14.73 | 5–8 in 2021-08-16 | 0.24 lb |
| Largemouth Bass | 8.97 | 15–19 in 2021-08-16 | 1.53 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.
Black Bullhead
Bluegill
Yellow Perch
Black Crappie
From the 2021-08-16 survey
Sleepy Eye is a smaller sized lake (240 acres) located adjacent to the City of Sleepy Eye in Brown County. A large city-owned access with a double cement boat ramp is located on the north shore within the Sleepy Eye Sportsmen's Park. Sleepy Eye Lake has 4 miles of shoreline and a maximum depth of 21 feet. The…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Sleepy Eye Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — Sleepy EyeFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — Sleepy EyeFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — Sleepy EyePublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
21 ft
Average depth
7 ft
Surface area
241 acres
Shoreline
4.3 mi
Littoral zone
84%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
11 sq mi
HydroLAKES / HydroSHEDS
Elevation
994 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Sleepy Eye Lake #1Public
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Sleepy Eye Lake
Compare lakeside cabins, hotels, and vacation rentals near Sleepy Eye Lake in Brown 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 Sleepy Eye Lake
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Fish Species
Click a species to see every lake where it is documented.
Fishing Sleepy Eye Lake
Water Quality Trend: Worsening
Based on 4 years of monitoring (2020–2023).
Water clarity
Worsening4 years
Phosphorus
Worsening+13.95 µg/L/yr4 years
Chlorophyll-a
Worsening+7.3 µg/L/yr4 years
Ice season
Typical ice-out
Mar 27
Earliest Mar 6, 2017 · Latest Apr 18, 2013
Typical ice-in
Nov 25
Earliest Nov 5, 1991 · Latest Dec 18, 2015
Most recent ice-out
Apr 8
2019
28 observations · Minnesota PCA ice records
Reservoir Info (USACE NID)
Sleepy Eye Lake is a man-made reservoir impounded by the Sleepy Eye Control (completed 1949), built primarily for recreation on the County Ditch 5; gravity-type dam, 8 ft tall and 35 ft long.
- Surface area
- 227 ac
- Normal storage
- 2,300 ac-ft
- Max storage
- 2,975 ac-ft
- Drainage area
- 1.5 sq mi
- Hazard class
- Low
- Owner
- City of Sleepy Eye
Source: USACE National Inventory of Dams, NID ID MN00754 · Operator website · Matched by proximity (0.36 km)
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Sleepy Eye Lake under Clean Water Act (NPDES) discharge permits.
- Edward Berkner FarmSleepy Eye · 4.2 mi away · NPDES MN0071277
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Nearby Lakes in Brown County
Frequently asked questions about Sleepy Eye Lake
Where is Sleepy Eye Lake?
- Sleepy Eye Lake is a lake in Brown County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Sleepy Eye Lake?
- Sleepy Eye Lake in Brown County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3.3 ft visibility. Phosphorus: 39.5 µg/L. Chlorophyll-a (algae): 18.7 µg/L. Maximum depth: 21 ft. Surface area: 240.82 acres.
Is Sleepy Eye 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 Sleepy Eye Lake?
- Sleepy Eye Lake typically sits around 52°F at the surface in October, from 96 EPA Water Quality Portal field readings (2017–2023). That is a typical value for the month, not a live reading.
How deep is Sleepy Eye Lake?
- Sleepy Eye Lake has a maximum depth of 21 feet and an average depth of 7 feet. The lake covers 240.82 acres.
What fish are in Sleepy Eye Lake?
- Fish species found in Sleepy Eye Lake include black bullhead, black crappie, bluegill, channel catfish, common carp, hybrid sunfish, largemouth bass, northern pike, walleye, yellow perch. Sleepy Eye Lake is located in Brown County, Minnesota.
What did the DNR fisheries survey find at Sleepy Eye Lake?
- Minnesota DNR's Targeted Survey on August 16, 2021 caught 15.17 walleye per gill net at Sleepy Eye Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Sleepy Eye Lake’s water-quality measurements separately, and the water-quality trend over 4 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Sleepy Eye Lake thaw?
- Sleepy Eye Lake typically has ice-out around Mar 27. Ice typically forms around Nov 25. The open water season is approximately 243 days.
Are there boat ramps on Sleepy Eye Lake?
- Sleepy Eye Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Sleepy Eye Lake #1. Public access is listed as yes.
Can I fish at Sleepy Eye Lake?
- Sleepy Eye 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 Sleepy Eye Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Brown County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Minnesota River Watershed, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
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State Parks Near Sleepy Eye Lake
Other Lakes in Minnesota
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Where this data comes from
195 measurements from 1 monitoring station, 2020–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA195 samples · 2020–2023
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Turbidity, Nephelometric Method
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate