Hanska Lake
Hanska Lake in Brown County, Minnesota has a water quality grade of F (Algae-prone). Water clarity: 1 ft visibility. Phosphorus: 219 µg/L. Chlorophyll-a (algae): 98.8 µg/L. Maximum depth: 16 ft. Surface area: 1794.96 acres.
- Clarity
- 1 ft
- Typical in August
- 74°F
- Max depth
- 16 ft
- Area
- 1,795 acres
- Type
- Hypereutrophic
- Trend
- ↓ Declining
- Public access
- Yes
- Ice-out
- Apr 3
- Open water
- 249 days
Grade F measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Hanska Lake →
Next lake in Brown County
Hanska Lake is a 1,795-acre highly nutrient-loaded hypereutrophic lake in Brown County, Minnesota with a maximum depth of 16 feet (5-foot average). Water quality is graded F based on 2 sampling years through 2023. Overall water quality is declining over recent sampling years. The lake supports 16 documented fish species including bigmouth buffalo, black bullhead, and black crappie. Public access is available with 1 public boat landing. Compared to the 3 other monitored lakes in Brown County, Hanska Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-10-11. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyAlgae risk
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.
Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom
Water Quality Grade: F (Algae-prone)
Very murky, less than 1 ft of visibility. Phosphorus level: 219 µg/L. Chlorophyll-a: 98.8 µg/L. Trophic State Index: 78.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1 ft | Not graded |
| Phosphorus | 219 µg/L | Poor |
| Chlorophyll-a (Algae) | 98.8 µg/L | Poor |
| Trophic State Index (TSI) | 78 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Where to stay near Hanska Lake
Compare lakeside cabins, hotels, and vacation rentals near Hanska 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Hanska Lake are listed below.
Top-rated places to stay near Hanska Lake
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
Hanska Lake typically sits around 74°F at the surface in August. Summer average is about 77°F. Usually warmest in Jun (about 78°F) and coldest in Oct (about 48°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 57 field readings (2021–2023) via the EPA Water Quality Portal. See the full Hanska Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 16 ft |
| Average Depth | 4.5 ft |
| Surface Area | 1,795 acres |
| Shoreline Length | 21.3 mi |
| Littoral Zone | 99% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Godahl LandingPublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Hanska Lake
DNR Fisheries Survey Summary
15 surveys on file from MN DNR Fisheries. Most recent: 2025-08-18 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Bullhead | 74.83 | 0.58 lb |
| Fathead Minnow | 55.27 | 0.01 lb |
| Black Crappie | 32.09 | 0.25 lb |
| OSS | 19.60 | 0.04 lb |
| Bluegill | 16.75 | 0.3 lb |
| Walleye | 15.02 | 1.32 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.
Black Bullhead
Black Crappie
Bluegill
Walleye
From the 2025-08-18 survey
Hanska is a large-sized lake (1,794 acres) located west of the City of Hanska in Brown County. A large state-owned access with paved parking and a double cement boat ramp is present on the southeast shore. There are also two smaller boat ramps at the northwest end of the lake (Geiger Point and Godahl). There are…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Hanska Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — HanskaFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — HanskaFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — HanskaPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 4 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.024 m/yr | 4 |
| Phosphorus | ↓ Declining | +12.5 µg/L/yr | 4 |
| Chlorophyll-a | ↓ Declining | +11.25 µg/L/yr | 4 |
Ice Season
Historical ice data from Minnesota DNR (82 observations).
Estimated open water season: 249 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2007-03-01 (2007) | 1951-04-26 (1951) |
| Ice-In | 2007-11-22 (2007) | 2004-12-13 (2004) |
Most recent ice-out: 2008-04-11
EPA Impairment Status
Hanska Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MN08-0026-00 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Hanska Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- La Salle WwtpLa Salle · 4.6 mi away · NPDES MN0067458Recent violation
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.
County Ranking
Ranked #4 of 4 lakes in Brown County
Nearby Lakes With Higher Grades
Hanska Lake holds Grade F. 3 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Brown County
Frequently asked questions about Hanska Lake
What is the water quality grade for Hanska Lake?
- Hanska Lake in Brown County, Minnesota has a water quality grade of F (Algae-prone). Water clarity: 1 ft visibility. Phosphorus: 219 µg/L. Chlorophyll-a (algae): 98.8 µg/L. Maximum depth: 16 ft. Surface area: 1794.96 acres.
Is Hanska Lake safe to swim in?
- Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom. Hanska Lake has a water quality grade of F (Algae-prone). Algae concentration (chlorophyll-a) is 98.8 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Hanska Lake?
- Hanska Lake typically sits around 74°F at the surface in August, from 57 EPA Water Quality Portal field readings (2021–2023). That is a typical value for the month, not a live reading.
How deep is Hanska Lake?
- Hanska Lake has a maximum depth of 16 feet and an average depth of 4.5 feet. The lake covers 1794.96 acres.
What fish are in Hanska Lake?
- Fish species found in Hanska Lake include bigmouth buffalo, black bullhead, black crappie, bluegill, brown bullhead, channel catfish, common carp, freshwater drum, green sunfish, hybrid sunfish, largemouth bass, northern pike, walleye, white sucker, yellow bullhead, yellow perch. Hanska Lake is located in Brown County, Minnesota.
When does Hanska Lake thaw?
- Hanska Lake typically has ice-out around Apr 3. Ice typically forms around Dec 8. The open water season is approximately 249 days.
Are there boat ramps on Hanska Lake?
- Hanska Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Godahl Landing. Public access is listed as yes.
Explore Hanska Lake across LakeGrade
Depth, room, public access, and the state wake-sport rules
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Fish species and best lakes in Brown County
Species activity outlook by water temperature and season
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Very high nutrients, dense algae, poor clarity
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Where this data comes from
668 measurements from 3 monitoring stations, 2020–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA668 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 (3)
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
Impairment status from EPA ATTAINS 303(d) database
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