Duck Lake
Hennepin County, MinnesotaView mapDirections
Minnesota PCA publishes the water-quality measurements for Duck Lake. Here is what has been measured.
- Eutrophic
- Eurasian watermilfoil
- 20 ft max depth
Duck Lake in Hennepin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.9 ft visibility. Phosphorus: 30 µg/L. Chlorophyll-a (algae): 5.9 µg/L.
Duck Lake is a productive, nutrient-rich eutrophic lake in Hennepin County, Minnesota with an estimated average depth of about 20 feet. Overall water quality is declining over recent sampling years. Limited fish-species data available. No public access — the lake is private or restricted. Compared to the 80 other monitored lakes in Hennepin County, Duck Lake ranks #16 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-07. Methodology: how these readings are compared.
Swimming conditions
Readings onlyModerate 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. 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.
Murky, only visible to about 5.9 ft. Phosphorus 30 µg/L. Chlorophyll-a 5.9 µg/L. TSI 51.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.9ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 30µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 5.9µg/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. | 51 | 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 58°F at the surface in October. Summer average is about 76°F. Usually warmest in Jul (about 79°F) and coldest in Jan (about 37°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (37°F) to its warmest (79°F).
Typical surface water temperature by month, from 294 field readings (2011–2025) via the EPA Water Quality Portal. See the full Duck Lake water temperature breakdown →
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Duck Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fish Stocking History — DuckFish Stocking History · MN DNR LakeFinder
Lake Details
Max depth
~20 ft est.
Public access
No
Listed by Minnesota PCA
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Minnesota has not published bathymetry for Duck Lake.
Lake Size & Watershed
Watershed (drainage) area
0 sq mi
HydroLAKES / HydroSHEDS
Surface area
30 acres
HydroLAKES / HydroSHEDS
Shoreline
1.2 mi
HydroLAKES / HydroSHEDS
Elevation
912 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Stays via Stay22
Stays near Duck Lake
Compare lakeside cabins, hotels, and vacation rentals near Duck Lake in Hennepin 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 Duck Lake
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Fishing Duck 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+0.81 µg/L/yr5 years
Chlorophyll-a
Stable-0.12 µg/L/yr5 years
Nearby Lakes in Hennepin County
Frequently asked questions about Duck Lake
Where is Duck Lake?
- Duck Lake is a lake in Hennepin 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 Hennepin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.9 ft visibility. Phosphorus: 30 µg/L. Chlorophyll-a (algae): 5.9 µg/L.
Is Duck 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 Duck Lake?
- Duck Lake typically sits around 58°F at the surface in October, from 294 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Duck Lake?
- No published bathymetric survey covers Duck Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 20 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Can I fish at Duck Lake?
- Public access to Duck Lake is listed as no on the lake record, so confirm before you make the trip. 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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Where this data comes from
258 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
MNPCA258 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- Phosphorus by Colorimetry
- Analysis of Chlorophyll in Periphyton and Plankton
- 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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder