Path of Diminished Potential

Some government decision-makers are skeptical of such sweeping visions. Although Gov. Timothy M. Kaine (D) campaigned for office in 2005 on a promise to do a better job linking planning for transportation and land use, the effects of that promise are still trickling through the Virginia Department of Transportation. Dennis C. Morrison, district administrator for VDOT's Northern Virginia office, said that shrinking Route 7, which carries 65,000 cars a day and is projected to carry more than 90,000 by 2030, would probably never be an option, even if the design process started over today.

"Would VDOT consider reducing capacity on Route 7 to make it more community-friendly, pedestrian-friendly, bicycle-friendly?" Morrison asked. "I'd love to say yes. But where would you send all that traffic?"

Federal money, which will help pay for the Route 7 changes, come with conditions -- including the ability to widen a road in the future. Such funds could be jeopardized if Route 7's function as an arterial highway was altered.

Critics of the rail project's design say VDOT's traffic projections don't account for drivers who will start taking Metro or for traffic that a city grid would eliminate from Route 7 by providing alternative routes. The threat of losing federal highway dollars frustrates them, too -- as does the Federal Transit Administration's stringent criteria for helping to pay for Dulles rail. The FTA's rigorous review of the Dulles budget made it difficult to go for big-ticket features, such as a tunnel, or better-sited stations requiring more land, that accomplish the larger goal of urban rebirth, they say.

"The way that we unfortunately look at a lot of these projects is to look at the minimum short-term cost versus the longer-term benefit and the longer-term payoff," said Tom Sanchez, associate professor of urban affairs and planning at Virginia Tech.

Those who have helped shaped the Dulles rail project note that a number of design changes have been made to accommodate Fairfax's goal of transforming Tysons. Rick Stevens, the county Transportation Department's point man on Dulles rail, said VDOT has agreed to narrow the eight future lanes of Route 7 to 11 feet from the standard 12, to allow for two additional pedestrian crossings beneath the aerial line and to build eight-foot sidewalks.

"We've always emphasized that we need wider sidewalks, we need more pedestrian crosswalks, we need to slow traffic down," Stevens said.

Stevens also said it is not too late for street grids to be built -- including level intersections along Route 7 that cross beneath the elevated track. And he said that the interchange of routes 7 and 123 might yet be remade. Stevens does not envision a level intersection because the volume of traffic is too high. But an underpass such as the one on Connecticut Avenue through Dupont Circle might be an option.

"The rail line hasn't precluded that," he said.

Finally, there is the rail line itself: white concrete pillars supporting the tracks, futuristic walkways from stations to sidewalks, bicycle boxes and, at some stations, entrances designed expressly to link to pedestrian plazas. Dulles Transit Partners, the consortium building the $5.1 billion project, has promised stations that welcome pedestrian-friendly development; their detractors criticize the aerial walkways and second-floor plazas that have failed in other places, and they say that the ground levels would continue to be dominated by the automobile.

Ultimately, much of the future look of Tysons will be determined by the private sector -- including the owners of Tysons' two malls, which both have proposed tall, mixed-use projects along Route 123.

In the end, it will be many years, perhaps decades, before the success or failure of Tysons can be measured.

"It's like landscaping -- there's a certain dynamism to it," said Sanchez, the urban affairs professor at Virginia Tech.

"What you originally anticipated isn't exactly going to work. But something else might take its place and bring some vitality to it."