Oakland County, Michigan: drinking water report. Oakland County stretches north of Detroit, home to about 1.3 million residents in communities ranging from…
Oakland County stretches north of Detroit, home to about 1.3 million residents in communities ranging from affluent suburbs like Bloomfield Hills and Troy to more rural areas in the north. Most of the county receives treated water from the Great Lakes Water Authority, sourced from Lake Huron. Some northern communities operate independent groundwater systems drawing from glacial aquifers.
Lake Huron provides a clean source, and GLWA's treatment facilities are among the most advanced in the region. But Oakland County's industrial history – including automotive manufacturing, aerospace, and military operations – has left contamination in local groundwater. Selfridge Air National Guard Base in neighboring Macomb County has documented PFAS contamination that affects shared groundwater resources.
Michigan's adoption of MCLs for seven PFAS compounds means Oakland County utilities face stricter monitoring and treatment requirements than most states impose. According to the Michigan EGLE database, 11 public water systems in Oakland County reported PFAS detections during UCMR5 monitoring, with the highest readings in systems using supplemental groundwater.
If your provider draws primarily from GLWA's Lake Huron supply, your baseline quality is strong. Groundwater-dependent communities, particularly in northern and western Oakland County, should pay closer attention to PFAS monitoring data.
Check your water to see which source serves you and what has been detected. Our water filter guide covers options for both PFAS and lead, which remains a concern in older homes throughout metro Detroit. Pull your detailed report, and visit our Michigan page for statewide context.
Drinking water is one exposure route. These federal datasets also cover Oakland County, MI.
The EPA places Oakland County, MI 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.
59% of homes in Oakland County, MI were built before 1980, and 13% 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 Oakland County, MI averages 9.3 µg/m³, above 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