Michigan Gov. Gretchen Whitmer (D) is seeking to boost state drinking water spending by $120 million to help local water systems faced with having to spend $2.5 billion to replace lead service lines.

Whitmer called on the GOP-controlled legislature on March 5 to pass a budget that includes the increased spending, with more than half of the money going toward upgrading drinking water infrastructure.

The move is an attempt to pay part of the immense replacement costs mandated by the state’s strictest-in-the-nation lead and copper rule that took effect in the wake of the Flint water-contamination crisis....