Big Bass Lake
Marathon County, Wisconsin177 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Big Bass Lake. Here is what has been measured.
- Mesotrophic
- Impaired · Mercury
- 13 ft max depth
- Public access
Big Bass Lake in Marathon County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 6 ft visibility. Phosphorus: 19 µg/L. Maximum depth: 13 ft. Surface area: 177 acres.
Wisconsin DNR lists Panfish as common on Big Bass Lake. DNR survey details →
Big Bass Lake is a 177-acre mesotrophic lake in Marathon County, Wisconsin with a maximum depth of 13 feet. Overall water quality is improving over recent sampling years. The lake supports 3 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Public access is available with 1 public boat landing. Compared to the 3 other monitored lakes in Marathon County, Big Bass Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-09-27. Methodology: how these readings are compared.
Big Bass Lake covers about 180 acres in Marathon County. It has one public boat landing. For a place on the water, look through cabin and lake-house rentals near Big Bass Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Big Bass Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing3 species recorded
Swimming conditions
Readings onlyLow 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. Big Bass Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Big Bass 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 Big Bass Lake
These are the measurements Wisconsin DNR publishes for Big Bass 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 6 ft. Phosphorus 19 µg/L. TSI 49.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 19µg/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. | 49 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Big Bass Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Big Bass Lake typically sits around 56°F at the surface in October. Summer average is about 78°F. Usually warmest in Jun (about 80°F) and coldest in Oct (about 56°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (56°F) to its warmest (80°F).
Typical surface water temperature by month, from 99 field readings (2024–2025) via the EPA Water Quality Portal. See the full Big Bass Lake water temperature breakdown →
Wisconsin DNR lists Panfish as common on Big Bass Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Big Bass Lake’s water-quality measurements separately, and the water-quality trend over 6 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 1994. 1 station on file (most recent sample 2025).
Fish Species (DNR-rated)
Lake Details
Max depth
13 ft
Surface area
177 acres
Public access
Yes
Listed by Wisconsin DNR
Lake Size & Watershed
Watershed (drainage) area
2 sq mi
HydroLAKES / HydroSHEDS
Shoreline
1.9 mi
HydroLAKES / HydroSHEDS
Elevation
1,171 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Big Bass 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 Big Bass Lake
Compare lakeside cabins, hotels, and vacation rentals near Big Bass Lake in Marathon 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 Big Bass 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 →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Big Bass 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: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Improving-2.06 µg/L/yr6 years
EPA Impairment Status
Big Bass 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 WI10008654 · Official waterbody report
Nearby Lakes in Marathon County
Frequently asked questions about Big Bass Lake
Where is Big Bass Lake?
- Big Bass Lake is a lake in Marathon County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Big Bass Lake?
- Big Bass Lake in Marathon County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 6 ft visibility. Phosphorus: 19 µg/L. Maximum depth: 13 ft. Surface area: 177 acres.
Is Big Bass Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Big Bass 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 Big Bass Lake?
- Big Bass Lake typically sits around 56°F at the surface in October, from 99 EPA Water Quality Portal field readings (2024–2025). That is a typical value for the month, not a live reading.
How deep is Big Bass Lake?
- Big Bass Lake has a maximum depth of 13 feet. The lake covers 177 acres.
What fish are in Big Bass Lake?
- Fish species found in Big Bass Lake include Panfish, Largemouth Bass, Northern Pike. Big Bass Lake is located in Marathon County, Wisconsin.
What did the DNR fisheries survey find at Big Bass Lake?
- Wisconsin DNR lists Panfish as common on Big Bass Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Big Bass Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Big Bass Lake?
- Big Bass Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Big Bass Lake. Public access is listed as yes.
Can I fish at Big Bass Lake?
- Big Bass 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.
Explore Big Bass Lake across LakeQuality
Fish species and the cleanest lakes across Wisconsin
Fish species and best lakes in Marathon County
Species activity outlook by water temperature and season
Where to stay at Wisconsin's top lakes, each with its readings
Lakes in the Wisconsin River Watershed, ranked by water quality
Wisconsin's cleanest lakes, ranked on agency measurements
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Mesotrophic Lakes in Wisconsin
Where this data comes from
97 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX97 samples · 2020–2025
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
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