Lenawee County, Michigan: drinking water report. Lenawee County sits in southeastern Michigan, bordered by Ohio to the south.
Lenawee County sits in southeastern Michigan, bordered by Ohio to the south. Adrian, the county seat, along with Tecumseh, Hudson, and smaller communities depend on a mix of groundwater wells and Lake Erie-sourced water delivered through the Great Lakes Water Authority system. The county's agricultural landscape and aging infrastructure create distinct water quality challenges for its roughly 99,000 residents.
Michigan's legacy of industrial contamination and agricultural runoff affects water supplies across the southern tier of the state, and Lenawee County faces both issues. The county's groundwater wells draw from shallow aquifers vulnerable to nitrate contamination from decades of fertilizer application. Communities connected to the Lake Erie water system benefit from more consistent treatment, but face different concerns related to aging distribution pipes and potential lead service lines that remain in older neighborhoods throughout Adrian and Tecumseh.
PFAS contamination has emerged as a statewide concern in Michigan, with the state conducting more aggressive testing than most others. While Lenawee County hasn't appeared on the highest-profile PFAS cleanup lists like some northern Michigan counties, the widespread use of these chemicals in manufacturing and agriculture means detection is likely in some systems. Michigan adopted some of the nation's strictest PFAS standards in 2020, requiring utilities to test and report results that many other states wouldn't flag as violations.
Lead remains the most pressing concern for homes built before 1986, particularly in Adrian's older districts where partial lead service line replacements may have occurred over the years. The disruption from these partial replacements can actually increase lead levels temporarily. Agricultural counties like Lenawee also show elevated nitrate readings during spring runoff seasons when fertilizer application peaks, though most public systems keep levels below the federal 10 mg/L standard through blending and treatment adjustments.
Test your water if you live in a home built before 1986 or rely on a private well, which roughly 30 percent of county residents do. Michigan's agricultural patterns mean well water testing for nitrates and bacteria should happen annually, particularly if you have young children or pregnant family members. Check your water to see current data for your specific address, review our water filter guide for treatment options that address lead and PFAS, or get your detailed report showing contaminant trends over time. For broader context on Michigan's water challenges and regulations, visit our state page.