Power plant emissions account for 30% of water pollution from industrial sources in the United States. Heavy metals like lead, mercury, and arsenic don’t degrade.

Experts said the decision would sharply undercut the agency’s authority to protect millions of acres of wetlands under the Clean Water Act, leaving them subject to pollution without penalty.

In theory, pollution in those ephemeral streams will ultimately influence water many kilometers away that is, at least nominally, still regulated by the Clean Water Act," he said In 2023, during ...