The kind of toll lanes that Northern Virginia officials want to study for local highways can shrink drive times significantly, shift traffic off local roads and shorten the duration of peak morning and afternoon congestion, according to studies of similar toll lanes in California.

The High Occupancy Toll systems, in which lone motorists pay to use carpool lanes, are used by drivers of every income, usually about four times a week when in a hurry, according to the studies conducted by universities and independent consultants. Motorists who use the lanes give them high marks, saying they provide another option when their time is more valuable than their money.

The California drivers said the toll lanes move faster, seem safer and are less stressful than the alternative of stop-and-go traffic.

But the toll systems, dubbed "Lexus lanes" by some drivers and political opponents, are priced out of some motorists' reach, the surveys found. While the income levels of toll lane drivers mirror those in the regular lanes, affluent drivers use them more often. In one of the toll lanes, the percentage of drivers earning $40,000 to $60,000 dropped 15 percent over three years.

The lanes also did not stop traffic from growing worse overall on the two California highways, in San Diego and Orange County.

The Virginia Department of Transportation wants to find out how such toll lanes might work in the traffic-choked Washington region.

It has applied for $1 million in federal funds to study the idea on Northern Virginia roads, including the Dulles Toll Road, parts of Interstate-95 and on I-66 inside the Capital Beltway, where all lanes are restricted to two or more passengers during peak times.

The goals are to make highways function more efficiently by using otherwise wasted road space and giving motorists in a hurry a new way to move faster.

As the population has grown in southern California, so, too, has the number of vehicles crowding the highways, including those with toll lanes. However, officials say, the ability to move more vehicles in the free-flowing carpool lanes has slowed the rate at which congestion worsens.

"If you're going through during the peak of the peak, the only consolation is that it would be a lot worse without HOT lanes," said Greg Hulsizer, general manager for Cofiroute Global Mobility, the private company that operates HOT lanes for the Orange County Transportation Authority. "But if you can travel on either side of the peak, you certainly see improvement."

The tolls enjoy support even from people who can't -- or won't -- pay, largely because motorists are happy to have the toll payers leave more room in the regular lanes, California officials said. In San Diego, two-thirds of motorists surveyed who didn't use the toll lanes still approved of them.

Dan Beal, of the Automobile Club of Southern California, the country's largest AAA affiliate, said some motorists still think they're unfair. However, he said the "Lexus lane" moniker has faded with time.

"There's good data now that everyone values their time," said Beal, whose organization represents 5 million motorists. "You don't have to be wealthy to value your time. People use it when it's best for them."

Motorists who now use the High Occupancy Vehicle, or carpool, lanes on the Dulles Toll Road and I-95/395 typically get to their destination in half the time of other drivers, according to VDOT. Tom Farley, VDOT's Northern Virginia administrator, said the agency will need to study whether the more crowded HOV lanes, such as those on I-395 and I-66 inside the Capital Beltway, would have room to spare for toll payers or whether new lanes would need to be added.

Washington area supporters also are eyeing HOT lanes for Maryland, particularly on Route 50 and I-270, where HOV lanes often have room to spare. Then Maryland governor Parris N. Glendening (D) killed a HOT lane study in 2001, saying the system is unfair to lower-income motorists. A spokesman for his successor, Robert L. Ehrlich Jr. (R), said the new governor might consider the idea.

Because of the "Lexus lane" argument, HOT lanes have been a tough sell across the country. Beyond southern California, only Houston has them. They are being considered in Denver, Dallas, Minneapolis and Phoenix, said C. Kenneth Orski, editor of Innovation Briefs transportation newsletter.

Virginia officials say Gov. Mark R. Warner (D) wanted to consider HOT lanes as a way to use existing highways more efficiently. Supporters say it's time traffic officials charge for time-based convenience. After all, they say, utility companies raise electricity rates at peak times, and restaurants charge more for Friday night dinner than an Early Bird special.

HOT lanes depend on motorists attaching electronic responders to their vehicles, similar to Virginia's Smart Tag or Maryland's E-ZPass.

In California, the transponders trigger the toll, which is deducted from the motorist's prepaid account. The toll price varies by time of day or by the amount of traffic. Tolls range from 50 cents to $4.75 but can be as high as $8 if traffic comes to a halt during a major incident. Motorists pay the price posted when they enter the lane. Some HOT lanes are free for carpools; others charge a reduced rate.

At a time when new road and transit projects are costly and controversial, transportation experts say HOT lanes allow them to attack the worst congestion. By increasing tolls during busy times, highway officials can encourage people to drive outside the heaviest hours, smoothing out the peaks that outstrip a road's capacity and cause regular backups. The tolls must be priced so that the carpool lanes remain free-flowing, or they lose their advantage over the regular lanes.

Hulsizer said drivers in the Orange County toll lanes save 30 to 60 minutes on a 10-mile drive during the rush. In San Diego, studies show the toll lanes save up to 20 minutes over eight miles, said Garry Bonelli, spokesman for the San Diego Association of Governments.

The $29 million in revenue from the Orange County tolls last year went to operate the road and pay off the debt of building the toll lanes, Hulsizer said. The $2 million in revenue that San Diego collected last year from its existing carpool lanes was split between operating the system and paying for new express bus service in the corridor, Bonelli said.