Rock Lake

Jefferson County, Wisconsin

OverviewFacts & Figures

Physical Characteristics

Surface Area (Acres)1,365
Maximum Depth (ft)60
Mean Depth (ft)16
Shoreline (miles)—
Bottom Composition30% sand, 30% gravel, 0% rock, 40% muck
Water Clarity — Secchi Depth (ft)—
Trophic Status—
Drainage BasinDRAINAGE
Lake Classlake
Public Access—
Township—
GPS Coordinates43.07830° N, 88.93040° W
WBIC (DNR ID)830700

Fish Species

5 species documented

AbundantCommonPresentRare
SpeciesAbundanceLast Survey
Largemouth BassCommon—
PanfishCommon—
Smallmouth BassCommon—
WalleyeCommon—
Northern PikePresent—

Boat Landings

4 landings

NameTypeRampTrailersFee♿
Rock Lake County Park Boat RampRAMP—Gr25YesNo
Elm PointRAMP—1-5YesNo
Ferry Park LandingRAMP—1-5YesNo
Sandy Beach Boat RampRAMP—Gr25YesYes

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
Banded Mystery SnailConfirmed—
Chinese Mystery SnailConfirmed—
Curly-Leaf PondweedConfirmed—
Eurasian Water-MilfoilConfirmed—
Hybrid Eurasian / Northern Water-MilfoilConfirmed—
Spiny NaiadConfirmed—
Yellow IrisConfirmed—
Zebra MusselConfirmed—

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