Lead in Wisconsin Drinking Water

Wisconsin has roughly 150,000 lead service lines still in the ground — buried pipes connecting individual buildings to the water main. Milwaukee alone has more than 65,000. When water sits in those pipes overnight, lead leaches into the water; the longer it sits, the higher the concentration. There's no safe level of lead exposure for children — it impairs cognitive development at concentrations far below the federal Action Level of 15 parts per billion.

The current federal Action Level (15 ppb) is not a 'safe' threshold — it's a system-wide trigger requiring corrosion control and lead service line replacement when more than 10% of sampled homes exceed it. The 2024 Lead and Copper Rule Improvements tighten the action level to 10 ppb starting in 2027 and require all lead service lines in the country to be replaced within 10 years. Wisconsin is moving on this — Milwaukee is replacing about 1,200 lines per year, federal infrastructure money has accelerated programs in many smaller systems, and the DNR maintains a public service line inventory.