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LakeQuality

Okauchee Lake Site

Waukesha County, Wisconsin1,210 acresView mapDirections

Wisconsin DNR publishes the water-quality measurements for Okauchee Lake Site. Here is what has been measured.

Clarity
4.6 ft
Murkier than most
Secchi · sampled 2024
Phosphorus
16.2 µg/L
Typical for Wisconsin
Measured by Wisconsin DNR
Max depth
90 ft
Bathymetric survey
Area
1,210 acres
Surface area
Type
Mesotrophic
Trophic class
Trend
Improving
7 years of samples
  • Mesotrophic
  • Impaired · Nutrients (phosphorus, nitrogen)
  • 3 aquatic invasives
  • 90 ft max depth
  • Public access

Okauchee Lake Site in Waukesha County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 4.6 ft visibility. Phosphorus: 16.2 µg/L. Maximum depth: 90 ft. Surface area: 1210 acres.

Wisconsin DNR lists Musky as common on Okauchee Lake Site. DNR survey details →

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Okauchee Lake Site is a 1,210-acre mesotrophic lake in Waukesha County, Wisconsin with a maximum depth of 90 feet. Overall water quality is improving over recent sampling years. The lake supports 6 documented fish species including Musky, Panfish, and Largemouth Bass. Public access is available. Compared to the 34 other monitored lakes in Waukesha County, Okauchee Lake Site ranks #34 for water quality.

Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2024-08-28. Methodology: how these readings are compared.

Okauchee Lake Site covers about 1,200 acres in Waukesha County. For a place on the water, look through cabin and lake-house rentals near Okauchee Lake Site on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.

What Okauchee Lake Site is good for

From access and monitoring records, not editorial picks.

  • Fishing6 species recorded
  • Deep water90 ft surveyed max depth
  • Big water1,210 acres

Swimming conditions

Readings only

Recreation 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. Okauchee Lake Site is listed impaired under Clean Water Act §303(d) (IR 5R) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.

Whether Okauchee Lake Site is safe to swim in today is a call for the Wisconsin Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Okauchee Lake Site

These are the measurements Wisconsin DNR publishes for Okauchee Lake Site, 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 4.6 ft. Phosphorus 16.2 µg/L. TSI 50.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)4.6ftMeasured, not scored

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorus16.2µg/LGood
GoodFairPoor
Chlorophyll-a (algae)No reading

The green pigment in algae — a direct measure of how much algae is in the water.

Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a.50Mesotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Okauchee Lake Site

Answers come straight from the public measurements and survey records on this page.

DNR fisheries survey

Wisconsin DNR lists Musky as common on Okauchee Lake Site.

A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Okauchee Lake Site’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.

WI DNR Lake Profile

Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1995. 17 stations on file (most recent sample 2025).

DNR Assessment
Reported
Trophic State Index 45 (mesotrophic) · 5-year average

Fish Species (DNR-rated)

Musky(Common)Largemouth Bass(Common)Northern Pike(Common)Panfish(Present)Smallmouth Bass(Present)Walleye(Present)

Lake Details

Max depth

90 ft

Surface area

1,210 acres

Public access

Yes

Listed by Wisconsin DNR

Stays via Stay22

Stays near Okauchee Lake Site

Compare lakeside cabins, hotels, and vacation rentals near Okauchee Lake Site in Waukesha County, Wisconsin — 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 Okauchee Lake Site

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.

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Follow Okauchee Lake Site’s readings

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Fish Species

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

Fishing Okauchee Lake Site

Invasive & Introduced Species

Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.

Banded Mystery SnailChinese Mystery SnailCurly-Leaf PondweedEurasian Water-MilfoilHybrid Eurasian / Northern Water-MilfoilPurple LoosestrifeZebra MusselStarry Stonewort

Based on 7 years of monitoring (2020–2026).

  • Water clarity

    Improving

    7 years

  • Phosphorus

    Stable

    -0.09 µg/L/yr7 years

  • Chlorophyll-a

    Improving

    -0.4 µg/L/yr2 years

See year-by-year chart →

EPA Impairment Status

Okauchee Lake Site is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5R).

Causes of impairment

Nutrients (phosphorus, nitrogen)

Designated uses not supporting: Aquatic life, Recreation.

Source: EPA ATTAINS assessment unit WI10009840 · Official waterbody report

Nearby Lakes in Waukesha County

Frequently asked questions about Okauchee Lake Site

Where is Okauchee Lake Site?

Okauchee Lake Site is a lake in Waukesha County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.

What is the water quality of Okauchee Lake Site?

Okauchee Lake Site in Waukesha County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 4.6 ft visibility. Phosphorus: 16.2 µg/L. Maximum depth: 90 ft. Surface area: 1210 acres.

Measurements on this page ↑

Is Okauchee Lake Site safe to swim in?

Nutrient and algae readings are not a swimming clearance. Okauchee Lake Site is listed impaired under Clean Water Act §303(d) (IR 5R) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.

Swimming on this page ↑

How deep is Okauchee Lake Site?

Okauchee Lake Site has a maximum depth of 90 feet. The lake covers 1210 acres.

What fish are in Okauchee Lake Site?

Fish species found in Okauchee Lake Site include Musky, Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike, Walleye. Okauchee Lake Site is located in Waukesha County, Wisconsin.

Fish on this page ↑

What did the DNR fisheries survey find at Okauchee Lake Site?

Wisconsin DNR lists Musky as common on Okauchee Lake Site. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Okauchee Lake Site’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.

DNR on this page ↑

Can I fish at Okauchee Lake Site?

Public access to Okauchee Lake Site is listed as yes on the lake record. Seasons, size and bag limits, and whether you need a license are set by Wisconsin's fish and wildlife agency, so check its current regulations before you go.

State Parks Near Okauchee Lake Site

Where this data comes from

19 measurements from 2 monitoring stations, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Wisconsin Department of Natural ResourcesWIDNR_WQX19 samples · 2020–2024

Analytical methods

  • Phosphorus by Colorimetry
Monitoring station identifiers (2)

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

Fish and recreation data from Wisconsin DNR Lakes