The Washington Post, citing new Census Bureau figures, reported that as jobs have spread out from metropolitan Washington and into the suburbs of Virginia and Maryland, so have the traffic snarls.
Nearly a quarter of the workers in Virginia's Prince William County and a fifth of workers in Maryland's Prince George's County log hour-plus commutes, more than double the national figure.
The new numbers also show, however, that a sizable number of the hour-plus commuters spend that time on mass transit. In addition, a growing share of people work at home, avoiding the commute entirely, although they remain a small fraction of the local workforce.
The Post notes that the Washington area's long commutes are not unique. Several suburbs of San Francisco, Chicago, and Atlanta also have one-way commutes averaging a half-hour or more. And the census figures show that workers in three New York boroughs commute an average of at least 40 minutes each way.
The Washington region's use of subways, buses, and trains to get to work already is well above the national level, according to the Post. Metrorail is jammed at commuting times, even though tourist traffic has fallen off lately. Virginia commuter rail is among the country's fastest growing, and ridership also is increasing on lines between Maryland and the District of Columbia.
Transportation experts said it's difficult to know from the census data how many people are traveling farther to work and how many are simply spending more time sitting in traffic.
But it is clear that more people are living and working farther apart, often in areas with little convenient public transportation, said Ronald Kirby, director of transportation planning for the Metropolitan Washington Council of Governments.
"Travel patterns now are more suburban cul-de-sac to suburban office park," Kirby said. "People tend to do that riding alone. There's no transit to make that trip convenient, and there's no benefit to carpooling."
Experts tell the Post that cheaper housing costs in the far suburbs and drivers' growing tendency to climb into their cars alone feed the sprawl.
"If you look at people's commutes and the cost of the long commutes, you could very easily reach the conclusion that they must be nuts," said Alan E. Pisarski, a national expert on commuting patterns. "But if you look at housing plus transportation costs as a total picture, you find that the sum in many instances is less."
Washington, D.C., area has emerged as one of the worst places in the country for commuting times, with an increasing number of workers spending an hour or more getting to work.