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Omsrud Lake

NR
Not yet rated
1 ft clear · Hypereutrophic
Limited DataHypereutrophic

Omsrud Lake in Brown County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1 ft visibility. Phosphorus: 199 µg/L. Chlorophyll-a (algae): 120 µg/L.

Clarity
1 ft
Mean depth
~10 ft est.
Public access
Yes

Next lake in Brown County

FHanska Lake1 ft clear · Brown CountyView →
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Why Omsrud Lake has no grade

We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Omsrud Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, phosphorus and algae (chlorophyll-a).

Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.

Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.

Omsrud Lake is a lake in Brown County, Minnesota with an estimated average depth of about 10 feet. The lake supports 3 documented fish species including black bullhead, common carp, and yellow perch. Public access is available with 1 public boat landing.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2022-06-21. Grade methodology: LakeGrade methodology.

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Swimming Safety

Not rated

Limited data

Not rated for swimming — there is not enough monitoring data to judge this lake

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Water quality measurements for Omsrud Lake

These readings exist but do not meet the evidence bar for an A–F grade — see why.

Very murky, less than 1 ft of visibility. Phosphorus level: 199 µg/L. Chlorophyll-a: 120 µg/L. Trophic State Index: 78.

MetricValueGrade
Water Clarity (Secchi Depth)1 ftNot graded
Phosphorus199 µg/LNot graded
Chlorophyll-a (Algae)120 µg/LNot graded
Trophic State Index (TSI)78Hypereutrophic

Very high nutrients, dense algae, poor clarity

Where to stay near Omsrud Lake

Compare lakeside cabins, hotels, and vacation rentals near Omsrud 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.

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Lake Details

CharacteristicValue
Average Depth~10 ft est.
Public AccessYes

Depth marked “est.” is a modeled estimate from HydroLAKES, not a measured survey. Minnesota has not published bathymetry for Omsrud Lake.

Lake Size & Watershed

Watershed (drainage) area
2 sq mi
Surface area
200 acres
Mean depth (modeled estimate)
~10 ft est.
Shoreline
3.2 mi
Elevation
997 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.

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Hanska Lake (South)Public

Fish Species

Click a species to see every graded lake where it is documented.

Fishing Omsrud Lake

Regulated Pollution Sources Nearby

1 EPA-permitted facility operate within about 5 miles of Omsrud Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.

  • Hanska Wwtp
    Hanska · 3.7 mi away · NPDES MN0052663
    Recent 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.

Graded lakes near Omsrud Lake

Omsrud Lake has no grade, but these lakes within a short drive do.

Nearby Lakes in Brown County

Frequently asked questions about Omsrud Lake

What is the water quality grade for Omsrud Lake?

Omsrud Lake in Brown County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1 ft visibility. Phosphorus: 199 µg/L. Chlorophyll-a (algae): 120 µg/L.

Is Omsrud Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Omsrud Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Algae concentration (chlorophyll-a) is 120 µg/L. Always check local health department advisories before swimming.

How deep is Omsrud Lake?

No published bathymetric survey covers Omsrud Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 10 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.

What fish are in Omsrud Lake?

Fish species found in Omsrud Lake include black bullhead, common carp, yellow perch. Omsrud Lake is located in Brown County, Minnesota.

Are there boat ramps on Omsrud Lake?

Omsrud Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Hanska Lake (South). Public access is listed as yes.

Hypereutrophic Lakes in Minnesota

Where this data comes from

4 measurements from 1 monitoring station, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA4 samples · 2022

Analytical methods

  • Field measurement/observation, generic method
  • Phosphorus by Colorimetry
  • 10200 H ~ Chlorophyll a-b-c Determination
  • 2120 B ~ Color in Water by Visual Comparison
Monitoring station identifiers (1)

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

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