Decatur Lake

Green County, Wisconsin

OverviewFacts & Figures

Physical Characteristics

Surface Area (Acres)109
Maximum Depth (ft)10
Mean Depth (ft)
Shoreline (miles)
Bottom Composition0% sand, 0% gravel, 0% rock, 99% muck
Water Clarity — Secchi Depth (ft)
Trophic Status
Drainage BasinDRAINAGE
Lake Classflowage
Public Access
Township
GPS Coordinates42.65170° N, 89.41690° W
WBIC (DNR ID)879400

Fish Species

5 species documented

AbundantCommonPresentRare
SpeciesAbundanceLast Survey
CatfishCommon
Largemouth BassPresent
Northern PikePresent
PanfishPresent
Smallmouth BassPresent

Boat Landings

No boat landing data available.

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
Asiatic Clam (Corbicula)Confirmed
Curly-Leaf PondweedConfirmed
Eurasian Water-MilfoilConfirmed
Rusty CrayfishConfirmed

Data sourced from Wisconsin DNR lake surveys. Last scraped: 3/24/2026.

Decatur Lake — Facts & Figures | Stay Northern