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LakeQuality

Viola Lake

Burnett County, Wisconsin265 acresView mapDirections

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

Clarity
17 ft
Clearer than most
Secchi · sampled 2026
Phosphorus
18.2 µg/L
Typical for Wisconsin
Measured by Wisconsin DNR
Water temp
~73°F
Typical for Sep · EPA WQP
Max depth
34 ft
Bathymetric survey
Area
265 acres
Surface area
Type
Mesotrophic
Trophic class
  • Mesotrophic
  • Curly-Leaf Pondweed
  • 34 ft max depth
  • Public access

Viola Lake in Burnett County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 17 ft visibility. Phosphorus: 18.2 µg/L. Maximum depth: 34 ft. Surface area: 265 acres.

Wisconsin DNR lists Largemouth Bass as common on Viola Lake. DNR survey details →

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Viola Lake is a 265-acre mesotrophic lake in Burnett County, Wisconsin with a maximum depth of 34 feet. Overall water quality is improving over recent sampling years. The lake supports 4 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Public access is available with 1 public boat landing. Compared to the 29 other monitored lakes in Burnett County, Viola Lake ranks #7 for water quality.

Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-06-23. Methodology: how these readings are compared.

Viola Lake covers about 270 acres in Burnett County. It has one public boat landing. Vrbo is where to look for cabins and lake homes around Viola Lake, and Booking.com and Expedia search hotels near the lake for your dates.

What Viola Lake is good for

From access and monitoring records, not editorial picks.

  • Clear water17 ft of visibility
  • Boat launch1 documented ramp
  • Fishing4 species recorded
  • Deep water34 ft surveyed max depth

Swimming conditions

Readings only

Low algae

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. Check local advisories before you swim.

Whether Viola Lake 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.

Compare swimming lakes near Hayward →

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Water quality measurements for Viola Lake

These are the measurements Wisconsin DNR publishes for Viola Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

Crystal clear, you can see 17 ft down. Phosphorus 18.2 µg/L. TSI 41.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)17ftMeasured, not scored

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

Total phosphorus18.2µg/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.41Mesotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Viola Lake

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

Water Temperature

Viola Lake typically sits around 73°F at the surface in September. Summer average is about 76°F. Usually warmest in Jul (about 79°F) and coldest in Apr (about 51°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
51°
Apr
63°
May
73°
Jun
79°
Jul
76°
Aug
73°
Sep
Oct
Nov
Dec

Column height runs from this lake’s coldest month (51°F) to its warmest (79°F).

Typical surface water temperature by month, from 18 field readings (2024–2026) via the EPA Water Quality Portal. See the full Viola Lake water temperature breakdown →

Blue-Green Algae (Cyanobacteria)

No current satellite reading

There’s no recent EPA CyAN cyanobacteria estimate for Viola Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was low (8,091 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 ↗

DNR fisheries survey

Wisconsin DNR lists Largemouth Bass as common on Viola Lake.

A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Viola Lake’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 1987. 1 station on file (most recent sample 2025).

DNR Assessment
Excellent · Deep Seepage lake
Trophic State Index 39 (oligotrophic) · 5-year average

Fish Species (DNR-rated)

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

Lake Details

Max depth

34 ft

Surface area

265 acres

Public access

Yes

Listed by Wisconsin DNR

Lake Size & Watershed

Watershed (drainage) area

1 sq mi

HydroLAKES / HydroSHEDS

Shoreline

3.2 mi

HydroLAKES / HydroSHEDS

Elevation

974 ft

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

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Viola 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 Viola Lake

Compare lakeside cabins, hotels, and vacation rentals near Viola Lake in Burnett 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 Viola Lake

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.

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

Follow Viola Lake’s readings

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Fish Species

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

Fishing Viola 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 Pondweed

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

  • Water clarity

    Improving

    7 years

  • Phosphorus

    Improving

    -1.69 µg/L/yr7 years

See year-by-year chart →

Nearby Lakes in Burnett County

Frequently asked questions about Viola Lake

Where is Viola Lake?

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

What is the water quality of Viola Lake?

Viola Lake in Burnett County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 17 ft visibility. Phosphorus: 18.2 µg/L. Maximum depth: 34 ft. Surface area: 265 acres.

Measurements on this page ↑

Is Viola Lake safe to swim in?

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Swimming on this page ↑

What is the water temperature of Viola Lake?

Viola Lake typically sits around 73°F at the surface in September, from 18 EPA Water Quality Portal field readings (2024–2026). That is a typical value for the month, not a live reading.

Temp on this page ↑

How deep is Viola Lake?

Viola Lake has a maximum depth of 34 feet. The lake covers 265 acres.

What fish are in Viola Lake?

Fish species found in Viola Lake include Panfish, Largemouth Bass, Northern Pike, Walleye. Viola Lake is located in Burnett County, Wisconsin.

Fish on this page ↑

What did the DNR fisheries survey find at Viola Lake?

Wisconsin DNR lists Largemouth Bass as common on Viola Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Viola Lake’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 ↑

Does Viola Lake have blue-green algae?

There is no recent EPA CyAN cyanobacteria estimate for Viola Lake (clouds, ice, or an off-season gap). The most recent reading was low (8,091 cells/mL). Blue-green algae can appear and clear within days, so check Wisconsin's current advisory before swimming.

Algae on this page ↑

Are there boat ramps on Viola Lake?

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

Access on this page ↑

Can I fish at Viola Lake?

Viola 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 Wisconsin's fish and wildlife agency, so check its current regulations before you go.

Access on this page ↑

Where this data comes from

68 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_WQX68 samples · 2020–2026

Analytical methods

  • Phosphorus by Colorimetry
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

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