Tests reveal elevated PFAS levels in Madison lakes

MADISON, Wis. (AP) — Tests have revealed elevated levels of man-made chemicals known as PFAS in Madison-area lakes, state environmental officials said Thursday.

The Department of Natural Resources collected samples last year from lakes Mendota, Monona, Upper Mud, Waubesa and Kegonsa, as well as along sections of the Yahara River between the lakes. Tests show PFAS levels in those water bodies that are higher than Lake Mendota upstream, the DNR said.

The department is working on establishing health standards for the chemicals. Even without them the study still provides a picture of the extent of contamination in the lake system, DNR Environmental Management Division Administrator Darsi Foss said.

Testing in 2019 showed PFAS in Starkweather Creek, which empties into Lake Monona. The Dane County Regional Airport's storm water system empties into Starkweather Creek. PFAS are found in fire-fighting foam used to extinguish blazes sparked by aircraft crashes.

The department next plans to sample fish from the lake system to decide whether to issue a consumption advisory, Foss said.