Census 2000 figures from 41 states show commuting times increased in some of the nation's biggest and fastest-growing cities and suburbs. In many of those metropolitan areas, an increasing share of workers traded in the car pool to make the trip solo.
"They're filling up on coffee, getting gas and going," Shannon Tenley said about the many solo drivers who stop by the Sheetz gas station in Frederick, Md., 50 miles north of Washington and 47 miles west of Baltimore. The morning rush there starts at 5 a.m., she says, as more people leave earlier to avoid heavy traffic.
National figures will not be available until after all 50 states get their data next week. But among findings in data released Wednesday for eight states and the District of Columbia are:
While most workers by far drive to work, commuting times also account for people who walk or take public transportation.
"Car pooling is still the most efficient form of alleviating traffic congestion. We proved that during various energy crises," said Ray Mundy, director of the Center for Transportation Studies at the University of Missouri-St. Louis.
"But typically, you have to get very crowded and run out of money" for other transportation projects before planners turn to car-pooling, he said.
The latest figures come from the 2000 census "long form," a survey, distributed to 20 million households that asked more detailed questions on topics such as income and education. Census 2000 figures released last year came from questions asked of all U.S. residents.
A separate Census Bureau survey released last year found the average one-way trip to work nationally lasted 24 minutes in 2000. Though not directly comparable, the 1990 census found the average trip to be 22 minutes.
Transportation planners say getting more people to use car pools remains an essential strategy for dealing with growing traffic problems around the country.
In fact, car-pooling rates increased a little or were relatively stable in several fast-growing metro areas such as Atlanta, Phoenix and Dallas. While there remain high numbers of solo drivers, residents of those places rely less on mass transit as an alternative.
Other factors - suburban office parks, more employers allowing flexible working hours - have increased the numbers driving solo, said Charles Dougherty of the Delaware Valley Regional Planning Commission
For instance, in the Philadelphia area, many jobs have relocated from downtown to the suburbs, where rents are cheaper.
"As development spreads out across the region, the density of travel along a particular route downtown decreases and the opportunities for ride-sharing go down," said Dougherty, who works on transportation issues in the Philadelphia region. "That's another problem of suburban sprawl."
Cheaper gas prices at the end of the decade also gave people less incentive to share rides, analysts said.
Richard Enkeboll of Burke, Va., said he would drive to and from his job in downtown Washington if he had a permanent parking space. Instead, he waits on car-pool lines that form on several downtown street corners during afternoon rush hour.
At these so-called slug lines, a solo driver typically picks up two or three people from the line headed toward the same destination. The payoff: being able to drive on HOV - "high-occupancy vehicle" - lanes, lanes reserved for car-poolers.
"It's the best thing there is," said Enkeboll, who cuts his travel time home in half to 20 minutes by car-pooling because the reduced HOV traffic generally allows faster driving. "Instead of driving, I can read a book."
Other states that received census data Wednesday were Delaware, Kentucky, Tennessee, Virginia and West Virginia.
By Genaro C. Armas