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LakeQuality

Upper Eau Claire Lake

B
Grade B — Good
Good · #11 of 24 lakes in the county · 18.7 ft clear · Oligotrophic · 1,024 acres · from A
Oligotrophic

Upper Eau Claire Lake in Bayfield County, Wisconsin has a water quality grade of B (Good). Water clarity: 18.7 ft visibility. Phosphorus: 11.9 µg/L. Maximum depth: 92 ft. Surface area: 1024 acres.

Clarity
18.7 ft
Typical in August
73°F
Max depth
92 ft
Area
1,024 acres
Type
Oligotrophic
Trend
Declining
Public access
Yes

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BRobinson Lake13.5 ft clear · Bayfield CountyView →
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Upper Eau Claire Lake is a 1,024-acre cold, clear oligotrophic lake in Bayfield County, Wisconsin with a maximum depth of 92 feet. Water quality is graded B based on 1 sampling years through 2026. Overall water quality is declining over recent sampling years. The lake supports 6 documented fish species including Musky, Panfish, and Largemouth Bass. Public access is available with 1 public boat landing. Compared to the 23 other monitored lakes in Bayfield County, Upper Eau Claire Lake ranks #11 for water quality.

Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-04-22. Grade methodology: LakeGrade methodology.

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Swimming Safety

Grade only

Low algae

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.

Good for swimming, clear water with low algae levels

Compare the safest swimming lakes near Hayward

Get alerts for Upper Eau Claire Lake

Water Quality Grade: B (Good)

Crystal clear, you can see 18.7 ft down. Phosphorus level: 11.9 µg/L. Trophic State Index: 37.

MetricValueGrade
Water Clarity (Secchi Depth)18.7 ftNot graded
Phosphorus11.9 µg/LGood
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)37Oligotrophic

Low nutrients, clear water, excellent for swimming

Where to stay near Upper Eau Claire Lake

Compare lakeside cabins, hotels, and vacation rentals near Upper Eau Claire Lake in Bayfield 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 Upper Eau Claire Lake

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Planning a whole trip? See where to stay at Wisconsin’s top lakes →

Water Temperature

Upper Eau Claire Lake typically sits around 73°F at the surface in August. Summer average is about 73°F. Usually warmest in Jul (about 78°F) and coldest in May (about 58°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
Apr
May
58°
Jun
69°
Jul
78°
Aug
73°
Sep
68°
Oct
Nov
Dec

Typical surface water temperature by month, from 20 field readings (20242025) via the EPA Water Quality Portal. See the full Upper Eau Claire Lake water temperature breakdown →

Blue-Green Algae (Cyanobacteria)

No current satellite reading

There’s no recent EPA CyAN cyanobacteria estimate for Upper Eau Claire Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was moderate (38,019 cells/mL) on November 22, 2025.

Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗

Lake Details

CharacteristicValue
Maximum Depth92 ft
Surface Area1,024 acres
Public AccessYes

Lake Size & Watershed

Watershed (drainage) area
80 sq mi
Shoreline
10.3 mi
Elevation
1,129 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Upper Eau Claire LakePublic

Fish Species

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

Fishing Upper Eau Claire 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.

Chinese Mystery SnailCurly-Leaf PondweedRusty Crayfish

WI DNR Lake Profile

Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1998. 1 station on file (most recent sample 2025).

DNR Assessment
Reported
Trophic State Index 38 (oligotrophic) · 5-year average

Fish Species (DNR-rated)

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

Based on 6 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Declining-0.561 m/yr6
Phosphorus Declining+2.43 µg/L/yr6
See year-by-year chart →

Reservoir Info (USACE NID)

Upper Eau Claire Lake is a man-made reservoir impounded by the Upper Eau Claire Lake (completed 1950), built primarily for recreation; gravity-type dam, 6 ft tall.

Surface area
1,030 ac
Normal storage
3,000 ac-ft
Max storage
4,000 ac-ft
Drainage area
8 sq mi
Hazard class
Low
Owner
Lundsberg, James

All listed purposes: Recreation;Other.

Source: USACE National Inventory of Dams, NID ID WI10053 · Operator website

County Ranking

Ranked #11 of 24 lakes in Bayfield County

Nearby Lakes in Bayfield County

Frequently asked questions about Upper Eau Claire Lake

What is the water quality grade for Upper Eau Claire Lake?

Upper Eau Claire Lake in Bayfield County, Wisconsin has a water quality grade of B (Good). Water clarity: 18.7 ft visibility. Phosphorus: 11.9 µg/L. Maximum depth: 92 ft. Surface area: 1024 acres.

Is Upper Eau Claire Lake safe to swim in?

Good for swimming, clear water with low algae levels. Upper Eau Claire Lake has a water quality grade of B (Good). Always check local health department advisories before swimming.

What is the water temperature of Upper Eau Claire Lake?

Upper Eau Claire Lake typically sits around 73°F at the surface in August, from 20 EPA Water Quality Portal field readings (2024–2025). That is a typical value for the month, not a live reading.

How deep is Upper Eau Claire Lake?

Upper Eau Claire Lake has a maximum depth of 92 feet. The lake covers 1024 acres.

What fish are in Upper Eau Claire Lake?

Fish species found in Upper Eau Claire Lake include Musky, Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike, Walleye. Upper Eau Claire Lake is located in Bayfield County, Wisconsin.

Does Upper Eau Claire Lake have blue-green algae?

There is no recent EPA CyAN cyanobacteria estimate for Upper Eau Claire Lake (clouds, ice, or an off-season gap). The most recent reading was moderate (38,019 cells/mL). Blue-green algae can appear and clear within days, so check Wisconsin's current advisory before swimming.

Are there boat ramps on Upper Eau Claire Lake?

Upper Eau Claire Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Upper Eau Claire Lake. Public access is listed as yes.

Oligotrophic Lakes in Wisconsin

Where this data comes from

74 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Wisconsin Department of Natural ResourcesWIDNR_WQX74 samples · 2020–2026

Analytical methods

  • Phosphorus by Colorimetry
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

Lake size & watershed from HydroLAKES (HydroSHEDS)

Fish and recreation data from Wisconsin DNR Lakes

Named boat-access points from the USGS National Boat Ramps inventory