Experts say it will probably take years for such activities as air travel to return to normal. Meanwhile, governments will still have to figure out how to shore up aging infrastructure, alleviate traffic congestion, support mass transit and accommodate the flying public.

The Maryland Department of Transportation has proposed slashing nearly $3 billion from its six-year capital budget. The cuts include delaying $900 million in road projects and postponing construction of a $500 million baggage-handling system and terminal connection at Baltimore-Washington International Marshall Airport. The state also plans to temporarily scrap some service for commuter buses and MARC commuter trains, which have ridership hovering at about 10 percent of normal.

“Everything has been hit across our system,” Maryland Transportation Secretary Gregory Slater said. “We have to find the least amount of impact to people, but people will see and feel some of this.”

Slater said his agency is trying to avoid layoffs by scaling back in other areas. For example, roads that typically would get a new layer of asphalt might instead just have potholes patched. Road crews will mow less often.

“I think people are already starting to see grass getting a little bit longer or less litter cleanup,” Slater said.

Nationwide, 18 states and 25 localities have recently canceled or delayed transportation projects valued at $10.9 billion, according to the American Road & Transportation Builders Association (ARTBA).

With most governors having declared construction to be essential during the pandemic, many states took advantage of unusually light traffic during stay-at-home orders to step up paving and other work. But much of the work that continued in the spring and early summer fell under contracts signed in the one or two years before the pandemic.

Alison Black, ARTBA’s chief economist, said she was struck by a decline in new contracts