PORTLAND — Workers in Maine’s largest metropolitan area enjoy shorter commuting times than the national average despite the area’s status as an employment hub for the state.

Commuters in the Portland-South Portland area spent an average of 24.1 minutes getting to work in 2013, slightly less than the national average of 25.8 minutes. Portland’s solo drivers and mass transit users also enjoy commute times quicker than the national average, while carpooling averages in Maine and nationwide are about the same.

Maine state officials and transit experts said the state’s favorable commuting climate exists despite its status as a rural state with a fanned-out workforce. Many workers commute long distances to the Bath Iron Works, government offices in Augusta, paper mills or other employment hubs.

State officials said proposals to create more rail service could reduce congestion and provide job access to more people. Also, carpooling remains a key piece of the puzzle.

An examination of traffic congestion in Maine is part of a yearlong series by The Associated Press that looks at the country’s infrastructure and traffic congestion. Without adequate planning, U.S. transportation officials warn that congestion will worsen over the next three decades as the nation’s population rises by an expected 70 million people, making gridlock the norm in many cities and suburbs.

About three-fourths of Maine’s workforce commutes alone by car, a feature in line with the national average, according to 2013 federal data. Maine has few major employers and they aren’t concentrated in one city, which means many workers commute long distances every day, putting stress on the roads. The toll on infrastructure is compounded by Maine’s cold, snowy winters and limited construction season.

The trend toward long-distance commuting also reflects trends at the national level, said Per Garder, a professor of civil engineering at the University of Maine.

“We have seen the same trend as the rest of the U.S. — that people are moving out of the service centers and living not only in nearby suburban municipalities but even ex-urban places 30 minutes away or so,” Garder said. “Workplaces on the other hand seem to be concentrating to the traditional urban centers.”

In Maine, solo driver commutes are partly offset by the number of residents who work from home, nearly 6 percent, said Ted Talbot, spokesman for the Maine Department of Transportation.

Maine has encouraged the use of carpooling to cut down on single-user car trips on highways. Federal data show about 10 percent of Mainers carpooled in 2013 and about 9 percent nationwide.

State government and the Maine Turnpike Authority have collaborated on the Go Maine program to link commuters with carpools and emergency rides home, Talbot said.

Even with carpools, long commuting distances keeps some Mainers in cars for long periods of time, but the state doesn’t suffer from much congestion, he said.

“My 50 miles commute from Portland to Augusta would be much different around Los Angeles,” Talbot said.

Some state legislators have pushed for commuter rail service between Portland and the Lewiston area, the state’s second-largest metro region. Drivers put about 1.45 million miles on the road per day in the Lewiston-Auburn area in 2013, federal data say.

Lewiston City Administrator Ed Barrett said linking Lewiston to rail would get cars off the road, reduce congestion and open up employment opportunities for people without cars.

“If we can find ways to help that traffic move, both to give people an alternative to a private automobile and give transit access to individuals who may not have an automobile, that would be economically beneficial,” he said.