Faucet Snail

Invasive SpeciesFound in 39 lakes

Faucet Snail appears on state infested-waters lists for 39 surface waters. Boaters and anglers moving gear in or out of those lakes carry a clean-drain-dry obligation under state law. 39 lakes — narrow enough that aggressive containment is still on the table. Most upper-Midwest invasives that established here did so quietly over a decade before anyone noticed, so a low number today is not a guarantee for tomorrow.

The presence of Faucet Snail does not directly change a lake's LakeGrade rubric score — the grade measures the water itself, not the species inhabiting it. But invasive presence is a meaningful adjacent signal worth reading alongside the grade.

Total Lakes

Minnesota

Wisconsin

Lakes with Faucet Snail

Lake	County	State	Grade	Depth
Lower Bottle Lake	Hubbard	MN	A	110 ft
Upper Bottle Lake	Hubbard	MN	A	55 ft
Superior Lake	Cook	MN	A	-
Superior Lake	St. Louis	MN	A	-
Paddock Lake	Kenosha	WI	A	32 ft
Long Lake	Hubbard	MN	A	135 ft
George Lake	Hubbard	MN	A	29 ft
Duck Lake	Hubbard	MN	A	23 ft
Boulder Lake	Hubbard	MN	A	28 ft
Tamarack Bay Lake	Cass	MN	A	69.8 ft
Second Crow Wing Lake	Hubbard	MN	A	35 ft
Sugar Lake	Itasca	MN	B	22 ft
Lake Winnibigoshish	Cass	MN	B	69.8 ft
Lower Phantom Lake	Waukesha	WI	B	12 ft
Little Lake Deep	Cook	MN	B	-
South Long Lake	Crow Wing	MN	B	47 ft
Upper Twin Lake	Hubbard	MN	B	12 ft
Fourth Crow Wing Lake	Hubbard	MN	B	10 ft
Third River Flowage Lake	Itasca	MN	B	69.8 ft
Teal Lake Deep	Cook	MN	C	-
Cut Foot Sioux Lake	Itasca	MN	C	-
Lower Twin Lake	Wadena	MN	C	26 ft
Stocking Lake	Wadena	MN	C	22 ft
Blackduck Lake	Beltrami	MN	C	28 ft
Bowstring Lake	Itasca	MN	C	32 ft
Little Winnibigoshish Lake	Itasca	MN	C	28 ft
Shawano Lake	Shawano	WI	C	39.5 ft
Third Crow Wing Lake	Hubbard	MN	C	35 ft
First Crow Wing Lake	Hubbard	MN	C	15 ft
Blackwater Lake	Itasca	MN	D	72 ft
Robinson Lake	Wabasha	MN	D	-
Little Cut Foot Lake	Itasca	MN	D	20 ft
Duluth Lake	St. Louis	MN	D	-
Knife Lake	Kanabec	MN	F	15 ft
Little Lake Inlet	Cook	MN	F	-
Little Lake Landing	Cook	MN	F	-
Lake Winneconne	Winnebago	WI	F	9 ft
Lake Butte des Morts	Winnebago	WI	F	9 ft
Lake Poygan	Winnebago	WI	F	11 ft

Frequently Asked Questions

How many lakes have faucet snail?

Faucet Snail has been documented in 39 graded lakes: 33 in Minnesota, 6 in Wisconsin.

Does faucet snail affect water quality?

Invasive species can significantly affect lake ecosystems. They may alter nutrient cycling, displace native species, and change water clarity. Lakes with faucet snail should be monitored for changes in water quality over time.

Invasives Found With Faucet Snail

Zebra Mussel

Co-occurs in 20 lakes · 688 total

Eurasian Watermilfoil

Co-occurs in 9 lakes · 859 total

New Zealand Mud Snail

Co-occurs in 7 lakes · 7 total

Round Goby

Co-occurs in 7 lakes · 19 total

Ruffe

Co-occurs in 7 lakes · 10 total

Spiny Waterflea

Co-occurs in 7 lakes · 93 total

Source: EPA National Aquatic Resource Surveys, 2026.