Fish Lake
Burnett County, WisconsinOligotrophic
Fish Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.
The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Among the 57 graded lakes in Burnett County, Fish Lake ranks 11 — in the top quartile locally.
Fish Lake has no invasive species recorded in Wisconsin state databases as of 2026, though prevention practices still apply at all access points. The state fisheries records do not list documented species for Fish Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-05-23. Grade methodology: LakeGrade methodology.
Watch Fish Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Good clarity, visible to about 14 ft. Phosphorus level: 12.6 µg/L. Trophic State Index: 40.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 14 ft | B |
| Phosphorus | 12.6 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 40 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.625 m/yr | 5 |
| Phosphorus | ↑ Improving | -0.71 µg/L/yr | 6 |
Recreation & Access
Location
County Ranking
Ranked #11 of 57 lakes in Burnett County
Nearby Lakes in Burnett County
More Wisconsin Lake Rankings
Other Grade A Lakes in Wisconsin
Washington County · Clarity: 11.8 ft
Washington County · Clarity: 12.6 ft
Walworth County · Clarity: 11 ft
Waukesha County · Clarity: 11.3 ft
Walworth County · Clarity: 20.2 ft
Kenosha County · Clarity: 10 ft
Oligotrophic Lakes in Wisconsin
DNR Reports & Resources
Wisconsin DNR Fisheries scientists publish multi-year survey reports for Fish Lake covering fish populations, stocking, water quality, and management. 6 reports on file.
- 2024Upper Clam River Watershed fishery survey, 2024Fisheries Survey · WI DNR · 2024 (PDF)
- 2021Yellow Lake fishery survey, 2021Fisheries Survey · WI DNR · 2021 (PDF)
- 2018Middle McKenzie comprehensive fisheries survey 2018Comprehensive Survey · WI DNR · 2018 (PDF)
- 2017Clam Lake comprehensive fisheries survey, 2017Comprehensive Survey · WI DNR · 2017 (PDF)
- 2016Lipsett Lake comprehensive fisheries survey, 2016Comprehensive Survey · WI DNR · 2016 (PDF)
- 2014Yellow Lake comprehensive fisheries survey, 2014Comprehensive Survey · WI DNR · 2014 (PDF)
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Public boat-access points from the USGS National Boat Ramps inventory
Most recent sample: 2026-05-23
Monitoring stations: 2
Where to stay near Fish Lake
Compare lakeside cabins, hotels, and vacation rentals near Fish Lake in Burnett County, Wisconsin — live availability and prices for your trip.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.