Round Lake
Oneida County, Wisconsin151 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Round Lake. Here is what has been measured.
- Eutrophic
- Impaired · Mercury
- Rusty Crayfish
- 15 ft max depth
- Limited data
Round Lake in Oneida County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 4.4 ft visibility. Phosphorus: 20.9 µg/L. Maximum depth: 15 ft. Surface area: 151 acres.
Wisconsin DNR lists Musky as common on Round Lake. DNR survey details →
Round Lake is a 151-acre productive, nutrient-rich eutrophic lake in Oneida County, Wisconsin with a maximum depth of 15 feet. The lake supports 6 documented fish species including Musky, Panfish, and Largemouth Bass. Compared to the 66 other monitored lakes in Oneida County, Round Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-02-24. Methodology: how these readings are compared.
What Round Lake is good for
From access and monitoring records, not editorial picks.
- Fishing6 species recorded
Swimming conditions
Readings onlyLimited data
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. Round Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Round 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.
Water quality measurements for Round Lake
These are the measurements Wisconsin DNR publishes for Round Lake, 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 4.4 ft. Phosphorus 20.9 µg/L. TSI 52.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 4.4ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 20.9µg/L | Good 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. | 52 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Round Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Round Lake typically sits around 38°F at the surface in November. Summer average is about 68°F. Usually warmest in Jun (about 68°F) and coldest in Feb (about 37°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (37°F) to its warmest (68°F).
Typical surface water temperature by month, from 14 field readings (2025–2026) via the EPA Water Quality Portal. See the full Round Lake water temperature breakdown →
Wisconsin DNR lists Musky as common on Round Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Round Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is stable. 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. 1 station on file (most recent sample 2026).
Fish Species (DNR-rated)
Lake Details
Max depth
15 ft
Surface area
151 acres
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Stays near Round Lake
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Fish Species
Click a species to see every lake where it is documented.
Fishing Round 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.
Water Quality Trend: Stable
Based on 7 years of monitoring (2020–2026).
Water clarity
Stable7 years
EPA Impairment Status
Round Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption.
Source: EPA ATTAINS assessment unit WI10007418 · Official waterbody report
Nearby Lakes in Oneida County
Frequently asked questions about Round Lake
Where is Round Lake?
- Round Lake is a lake in Oneida County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Round Lake?
- Round Lake in Oneida County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 4.4 ft visibility. Phosphorus: 20.9 µg/L. Maximum depth: 15 ft. Surface area: 151 acres.
Is Round Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Round Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
What is the water temperature of Round Lake?
- Round Lake typically sits around 38°F at the surface in November, from 14 EPA Water Quality Portal field readings (2025–2026). That is a typical value for the month, not a live reading.
How deep is Round Lake?
- Round Lake has a maximum depth of 15 feet. The lake covers 151 acres.
What fish are in Round Lake?
- Fish species found in Round Lake include Musky, Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike, Walleye. Round Lake is located in Oneida County, Wisconsin.
What did the DNR fisheries survey find at Round Lake?
- Wisconsin DNR lists Musky as common on Round Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Round Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
Explore Round Lake across LakeQuality
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Where this data comes from
18 measurements from 1 monitoring station, 2025–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX18 samples · 2025–2026
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
Impairment status from EPA ATTAINS 303(d) database
Fish and recreation data from Wisconsin DNR Lakes