Brown County, Wisconsin: drinking water report. Brown County in northeast Wisconsin has about 268,000 residents, anchored by Green Bay.
Brown County in northeast Wisconsin has about 268,000 residents, anchored by Green Bay. The Green Bay Water Utility draws from Lake Michigan, providing high-quality Great Lakes water to most of the county's population. The Fox River flows through the county into Green Bay, carrying a legacy of paper mill contamination that shaped the region's environmental history.
The lower Fox River was one of the most PCB-contaminated waterways in the country, the result of decades of paper mill operations that used PCB-containing carbonless copy paper. According to the Wisconsin DNR's 2024 remediation status report, over 6 million cubic yards of contaminated sediment have been removed or capped since the cleanup began, but fish consumption advisories remain in effect for the river and lower Green Bay.
Green Bay's Lake Michigan water supply avoids the Fox River contamination, but PFAS is a newer concern. The former Austin Straubel International Airport and Oneida Nation facilities have documented AFFF use. Wisconsin DNR's 2024 investigation found PFOS at 11 ppt in groundwater wells near the airport area.
Green Bay residents on the Lake Michigan supply benefit from a clean source that avoids the Fox River entirely. If you are on a private well in the county, particularly near the airport or industrial areas, testing for both PCBs and PFAS is recommended.
Check your water for data at your specific address. For private well users, a comprehensive test panel is a worthwhile investment. Our water filter guide covers systems for both municipal and well water. Pull your detailed report for trends, and visit our Wisconsin page for statewide data.
Drinking water is one exposure route. These federal datasets also cover Brown County, WI.
The EPA places Brown County, WI in Zone 2 - a moderate-risk category, with a predicted average indoor radon level between 2 and 4 pCi/L. Zone maps predict an area's radon potential from geology and existing indoor readings; they say nothing about a specific house. Testing is the only way to know your own level.
50% of homes in Brown County, WI were built before 1980, and 14% before 1950. Residential lead paint was banned in 1978, so housing age is the strongest available proxy for lead-paint exposure. This describes the county's housing stock, not any one home.
Modelled annual fine-particle pollution (PM2.5) in Brown County, WI averages 7.2 µg/m³, within the EPA's annual standard of 9 µg/m³. These are CDC modelled county estimates rather than readings from a specific monitor.
How radon zones work · Air quality by county · Lead exposure guide