The American Water Works Association estimated in 2016 that 6.1 million water service lines in the U.S. are lead-based, meaning a significant number of American households—somewhere between 15 and 22 million people—are routinely exposed to trace amounts of lead in their water. The industry group said a "reasonable estimate" for replacing each affected line was $5,000, a total cost of more over $30 billion. The 2016 figure was down from 10.2 million lines in 1991.
A more detailed 2019 report from the University of Minnesota found that while replacing the 100,000 existing lead-containing service lines in the state would cost between $1.52 billion and $4.12 billion over 20 years, it would lead to projected benefits of between $4.24 billion and $8.47 billion over that same period.