Johnson Falls Flowage 647

Marinette County, Wisconsin

OverviewFacts & Figures

Physical Characteristics

Surface Area (Acres)145
Maximum Depth (ft)37
Mean Depth (ft)9
Shoreline (miles)—
Bottom Composition70% sand, 10% gravel, 15% rock, 5% muck
Water Clarity — Secchi Depth (ft)—
Trophic Status—
Drainage BasinDRAINAGE
Lake Classflowage
Public Access—
Township—
GPS Coordinates45.26760° N, 88.17970° W
WBIC (DNR ID)533300

Fish Species

4 species documented

AbundantCommonPresentRare
SpeciesAbundanceLast Survey
Smallmouth BassCommon—
WalleyeCommon—
Northern PikePresent—
PanfishPresent—

Boat Landings

1 landing

NameTypeRampTrailersFee♿
Boat Launch #14 - Thunder RiverRAMP—6-10NoNo

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—
Eurasian Water-MilfoilConfirmed—
Rusty CrayfishConfirmed—

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

Johnson Falls Flowage 647 — Facts & Figures | Stay Northern