Duck Lake
Blue Earth County, Minnesota290 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Duck Lake. Here is what has been measured.
- Eutrophic
- Impaired · Mercury
- 25 ft max depth
- Public access
- Limited data
Duck Lake in Blue Earth County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2.8 ft visibility. Phosphorus: 105 µg/L. Chlorophyll-a (algae): 31.5 µg/L. Maximum depth: 25 ft. Surface area: 290.42 acres.
Minnesota DNR's Standard Survey on June 9, 2025 caught 0.60 walleye per gill net at Duck Lake. DNR survey details →
Duck Lake is a 290-acre productive, nutrient-rich eutrophic lake in Blue Earth County, Minnesota with a maximum depth of 25 feet. The lake supports 17 documented fish species including bigmouth buffalo, black bullhead, and black crappie. Public access is available with 1 public boat landing. Compared to the 4 other monitored lakes in Blue Earth County, Duck Lake ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-09-25. Methodology: how these readings are compared.
Duck Lake covers about 290 acres in Blue Earth County. It has one public boat landing. The median ice-out date is April 4, which is when the open-water season begins. For a place on the water, look through cabin and lake-house rentals near Duck Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Duck Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing17 species recorded
- Ice seasonIce-out around Apr 4
Swimming conditions
Readings onlyRecreation use not supported
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. Duck Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Duck 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 Duck Lake
These are the measurements Minnesota PCA publishes for Duck 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 2.8 ft of visibility. Phosphorus 105 µg/L. Chlorophyll-a 31.5 µg/L. TSI 66.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2.8ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 105µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 31.5µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 66 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Duck Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Duck Lake typically sits around 69°F at the surface in September. Summer average is about 73°F. Usually warmest in Aug (about 77°F) and coldest in May (about 60°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (60°F) to its warmest (77°F).
Typical surface water temperature by month, from 59 field readings (2016–2024) via the EPA Water Quality Portal. See the full Duck Lake water temperature breakdown →
Minnesota DNR's Standard Survey on June 9, 2025 caught 0.60 walleye per gill net at Duck Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Duck Lake’s water-quality measurements separately, and the water-quality trend over 4 years of monitoring is stable. 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: 2025-06-09 (Standard Survey).
13 surveys on file · most recent 2025-06-09 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluntnose Minnow | 58.41 | ||
| Bluegill | 35.75 | 4–8 in 2025-06-09 | 0.2 lb |
| Black Bullhead | 29.75 | 7–12 in 2025-06-09 | 0.63 lb |
| Largemouth Bass | 18.07 | 6–20 in 2025-06-09 | 1.39 lb |
| White Crappie | 15.08 | 5–13 in 2025-06-09 | 0.3 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.
Bluegill
Black Bullhead
Largemouth Bass
White Crappie
From the 2025-06-09 survey
Duck Lake is a 290-acre lake located on the north side of the city of Madison Lake in Blue Earth County. Duck Lake has a maximum depth of 25 feet. A county-maintained public access is located on the south end of the lake near the county park. Most of the shoreline has been altered by residential development and…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Duck Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — DuckFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — DuckFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — DuckPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
25 ft
Surface area
290 acres
Shoreline
2.7 mi
Littoral zone
80%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
4 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,010 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Duck 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 Duck Lake
Compare lakeside cabins, hotels, and vacation rentals near Duck Lake in Blue Earth 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Duck Lake are listed below.
Top-rated places to stay near Duck 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 Duck Lake
Water Quality Trend: Stable
Based on 4 years of monitoring (2020–2024).
Water clarity
Stable4 years
Ice season
Typical ice-out
Apr 4
Earliest Mar 7, 2000 · Latest Apr 30, 1988
Typical ice-in
Dec 1
Earliest Nov 4, 1991 · Latest Jan 7, 2024
Most recent ice-out
Apr 12
2023
73 observations · Minnesota PCA ice records
EPA Impairment Status
Duck 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, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN07-0053-00 · Official waterbody report
Nearby Lakes in Blue Earth County
Frequently asked questions about Duck Lake
Where is Duck Lake?
- Duck Lake is a lake in Blue Earth County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Duck Lake?
- Duck Lake in Blue Earth County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 2.8 ft visibility. Phosphorus: 105 µg/L. Chlorophyll-a (algae): 31.5 µg/L. Maximum depth: 25 ft. Surface area: 290.42 acres.
Is Duck Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Duck Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Duck Lake?
- Duck Lake typically sits around 69°F at the surface in September, from 59 EPA Water Quality Portal field readings (2016–2024). That is a typical value for the month, not a live reading.
How deep is Duck Lake?
- Duck Lake has a maximum depth of 25 feet. The lake covers 290.42 acres.
What fish are in Duck Lake?
- Fish species found in Duck Lake include bigmouth buffalo, black bullhead, black crappie, bluegill, bowfin (dogfish), common carp, freshwater drum, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, smallmouth buffalo, walleye, white crappie, white sucker, yellow bullhead, yellow perch. Duck Lake is located in Blue Earth County, Minnesota.
What did the DNR fisheries survey find at Duck Lake?
- Minnesota DNR's Standard Survey on June 9, 2025 caught 0.60 walleye per gill net at Duck Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Duck Lake’s water-quality measurements separately, and the water-quality trend over 4 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
When does Duck Lake thaw?
- Duck Lake typically has ice-out around Apr 4. Ice typically forms around Dec 1. The open water season is approximately 241 days.
Are there boat ramps on Duck Lake?
- Duck Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Duck Lake. Public access is listed as yes.
Can I fish at Duck Lake?
- Duck 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 Duck Lake across LakeQuality
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Fish species and best lakes in Blue Earth County
Species activity outlook by water temperature and season
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Minnesota's cleanest lakes, ranked on agency measurements
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Where this data comes from
26 measurements from 1 monitoring station, 2023–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA26 samples · 2023–2024
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
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
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate