Clear Lake
Le Sueur County, Minnesota279 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Clear Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Nutrients (phosphorus, nitrogen)
- 18 ft max depth
- Public access
- Limited data
Clear Lake in Le Sueur County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 1.2 ft visibility. Phosphorus: 309.5 µg/L. Chlorophyll-a (algae): 71.6 µg/L. Maximum depth: 18 ft. Surface area: 279.43 acres.
Clear Lake is a 279-acre highly nutrient-loaded hypereutrophic lake in Le Sueur County, Minnesota with a maximum depth of 18 feet. The lake supports 11 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 12 other monitored lakes in Le Sueur County, Clear Lake ranks #7 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-25. Methodology: how these readings are compared.
What Clear Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing11 species recorded
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. Clear Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Clear 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 Clear Lake
These are the measurements Minnesota PCA publishes for Clear 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 1.2 ft of visibility. Phosphorus 309.5 µg/L. Chlorophyll-a 71.6 µg/L. TSI 78.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 1.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 310µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 71.6µg/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. | 78 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Clear Lake
Answers come straight from the public measurements and survey records on this page.
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Clear Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was very high (1,870,682 cells/mL) on July 19, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Lake Details
Max depth
18 ft
Surface area
279 acres
Shoreline
2.9 mi
Littoral zone
71%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
3 sq mi
HydroLAKES / HydroSHEDS
Elevation
997 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Clear 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 Clear Lake
Compare lakeside cabins, hotels, and vacation rentals near Clear Lake in Le Sueur 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 Clear Lake are listed below.
Top-rated places to stay near Clear Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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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 Clear Lake
EPA Impairment Status
Clear 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: Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN40-0079-00 · Official waterbody report
Nearby Lakes in Le Sueur County
Frequently asked questions about Clear Lake
Where is Clear Lake?
- Clear Lake is a lake in Le Sueur County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Clear Lake?
- Clear Lake in Le Sueur County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 1.2 ft visibility. Phosphorus: 309.5 µg/L. Chlorophyll-a (algae): 71.6 µg/L. Maximum depth: 18 ft. Surface area: 279.43 acres.
Is Clear Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Clear Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
How deep is Clear Lake?
- Clear Lake has a maximum depth of 18 feet. The lake covers 279.43 acres.
What fish are in Clear Lake?
- Fish species found in Clear Lake include black bullhead, black crappie, bluegill, freshwater drum, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, white sucker, yellow perch. Clear Lake is located in Le Sueur County, Minnesota.
Does Clear Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Clear Lake (clouds, ice, or an off-season gap). The most recent reading was very high (1,870,682 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Clear Lake?
- Clear Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Clear Lake. Public access is listed as yes.
Can I fish at Clear Lake?
- Clear 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 Clear Lake across LakeQuality
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Where this data comes from
15 measurements from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA15 samples · 2025
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