For the first time in three decades, the federal government on Tuesday overhauled a rule aimed at reducing lead in drinking water across the country — a long-standing scourge made worse by the nation’s weathered and crumbling infrastructure.

The Environmental Protection Agency’s lead and copper rule, widely criticized as complicated, poorly enforced and too weak to protect the health of many Americans, has not been revised since 1991, when George H.W. Bush was president.