Gov. Rick Snyder of Michigan is scrambling to deal with a terrible water crisis created by his administration in the city of Flint, which is poor and has a black majority. The damage to the nearly bankrupt city and its nearly 100,000 residents by lead-tainted water caused by corrosion in the pipes has yet to be totaled, but there is no doubt that the state has a moral obligation to provide clean water immediately for the citizens and to devise a long-term solution, no matter how costly.

The governor, a Republican, did virtually nothing to help the city until an outpouring of rage from Flint residents, city leaders, journalists and independent researchers forced him to wake up and focus on the calamity, which started more than a year ago.

He had turned a blind eye, possibly because it was a destitute city whose elected officials had little political power and were under the thumb of an emergency manager Mr. Snyder had appointed. Or possibly because he wanted to maintain state control, he failed to call on the most obvious source of assistance, the Federal Emergency Management Agency. He finally sought, and got, aid from FEMA, which this week agreed to help with a long-term recovery plan.

Because of the state’s actions, some part of the water distribution system within Flint, possibly all of it, may need to be replaced at a cost that city officials estimate could be as high as $1.5 billion. And thousands of children with potential brain damage from lead poisoning may need monitoring, nutritional support and special education to mitigate the harm caused by this man-made disaster.