Mercer Lake
Oneida County, Wisconsin255 acresView mapDirections
No nutrient or algae sampling on record from Wisconsin DNR for this lake.
- 2 aquatic invasives
- 23 ft max depth
- Limited data
Mercer Lake in Oneida County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Maximum depth: 23 ft. Surface area: 255 acres.
Wisconsin DNR lists Musky as common on Mercer Lake. DNR survey details →
Mercer Lake is a 255-acre lake in Oneida County, Wisconsin with a maximum depth of 23 feet. The lake supports 6 documented fish species including Musky, Panfish, and Largemouth Bass.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-11-16. Methodology: how these readings are compared.
What Mercer Lake is good for
From access and monitoring records, not editorial picks.
- Fishing6 species recorded
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Mercer 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 Mercer Lake
These are the measurements Wisconsin DNR publishes for Mercer Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data.
Ask about Mercer Lake
Answers come straight from the public measurements and survey records on this page.
Wisconsin DNR lists Musky as common on Mercer Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Mercer Lake’s water-quality measurements separately. 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 2025).
Fish Species (DNR-rated)
Lake Details
Max depth
23 ft
Surface area
255 acres
Lake Size & Watershed
Watershed (drainage) area
4 sq mi
HydroLAKES / HydroSHEDS
Shoreline
4 mi
HydroLAKES / HydroSHEDS
Elevation
1,565 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Mercer Lake
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Follow Mercer Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Mercer 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.
Nearby Lakes in Oneida County
Frequently asked questions about Mercer Lake
Where is Mercer Lake?
- Mercer 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 Mercer Lake?
- Mercer Lake in Oneida County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Maximum depth: 23 ft. Surface area: 255 acres.
Is Mercer Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Mercer Lake?
- Mercer Lake has a maximum depth of 23 feet. The lake covers 255 acres.
What fish are in Mercer Lake?
- Fish species found in Mercer Lake include Musky, Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike, Walleye. Mercer Lake is located in Oneida County, Wisconsin.
What did the DNR fisheries survey find at Mercer Lake?
- Wisconsin DNR lists Musky as common on Mercer Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Mercer Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
Explore Mercer Lake across LakeQuality
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Where this data comes from
2 measurements from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX2 samples · 2025
Analytical methods
- Total Phosphorus After Block Digestion
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