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Lake Name:

a lake.
Lake Mendota ice boat

Lake Mendota ice boat
Photo by DNR

Contact information
For information on Lakes in Wisconsin, contact:
Wisconsin DNR Lakes
Division of Water
Bureau of Water Quality
DNR Contacts for Lake Mendota

Friends Of Lake Mendota (Flam) [exit DNR]

Middleton Beach Road Neighborhood Association [exit DNR]

Yahara Lakes Association Ltd [exit DNR]

Find A Lake > Dane County > Lake Mendota

Lake Mendota
Dane County, 9781 Acres

Water Quality

One measure of a lakes health is the trophic state, which relates to the amount of algae in the water. The average summer trophic state for the last 5 years was 54 (Eutrophic) and was determined using Secchi data. For a Two-Story lake, this is considered Poor.

Lake Mendota has been monitored by volunteers since 2016. Volunteers monitor water clarity with a black and white Secchi disk. Volunteers are the source of the majority of Wisconsin's lake water quality data, and their dedication is greatly appreciated. Additional monitoring has been done through projects funded in part by DNR Lake Grants and Aquatic Invasive Species Grants. Reports and graphs featuring data collected by volunteers, DNR staff and others can be viewed below.

Water Quality Reports and Graphs

Station NameStation IDMapMax YearReports
Lake Mendota - Central Deep Hole133318Map2020Details
Lake Mendota - Deep Central Region Coring Location10046986Map2016Details
Lake Mendota - Lake Mendota206Map1970Details
Lake Mendota - Pheasant Branch Deep Area10031991Map2016Details
Lake Mendota - West Side133536Map1990Details
Lake Mendota - Yahara Bay10031720Map2016Details
Lake Mendota - east end St. Cyr Rd10043399Map2014Details
Lake Mendota at Burrows Rd10043401Map2014Details
Lake Mendota at Upham Ct10043400Map2014Details