Lake Koshkonong

Jefferson, Dane, Rock County, Wisconsin

OverviewFacts & Figures

Physical Characteristics

Surface Area (Acres)10,595
Maximum Depth (ft)7
Mean Depth (ft)5
Shoreline (miles)—
Bottom Composition10% sand, 10% gravel, 0% rock, 80% muck
Water Clarity — Secchi Depth (ft)—
Trophic Status—
Drainage BasinDRAINAGE
Lake Classlake
Public Access—
Township—
GPS Coordinates42.87240° N, 88.96120° W
WBIC (DNR ID)808700

Fish Species

7 species documented

AbundantCommonPresentRare
SpeciesAbundanceLast Survey
PanfishCommon—
CatfishPresent—
Largemouth BassPresent—
MuskyPresent—
Northern PikePresent—
Smallmouth BassPresent—
WalleyePresent—

Boat Landings

4 landings

NameTypeRampTrailersFee♿
Bingham Road Boat RampRAMP—1-5NoNo
Vinne HaHa LandingRAMP—11-15NoNo
Lake Koshkonong AccessRAMP—6-10NoNo
Royce-Dallman County Park Boat RampRAMP—21-25NoNo

Invasive Species

Invasive species have been documented in or near this lake. Please clean, drain, and dry all watercraft and equipment before leaving to prevent spread.

SpeciesStatusFirst Detected
Curly-Leaf PondweedConfirmed—
Zebra MusselConfirmed—

Data sourced from Wisconsin DNR lake surveys. Last scraped: 4/30/2026.