Summer 2024’s record heat is creating problems for transportation infrastructure, from roads to rails.

New York’s Third Avenue Bridge, which swings open for ship traffic on the Harlem River, was stuck for hours after its metal expanded in the heat and it couldn’t close. Roads have buckled on hot days in several states, including Washington and Wisconsin. Amtrak warned passengers to prepare for heat-related problems hours before a daylong outage between New York and New Jersey; the risks to power lines and rails during high temperatures are a growing source of delays for the train system.

It doesn’t help that the worsening heat is hitting a U.S. infrastructure system that is already in trouble.

The American Society of Civil Engineers gave U.S. infrastructure an overall grade of C– in its latest national Infrastructure Report Card, released in 2021. While there has been some improvement — about 7.5 percent of U.S. bridges were in poor condit