By Amy Gardner
Washington Post Staff Writer
Wednesday, March 11, 2009

The federal government's formal commitment yesterday to a long-planned extension of Metro to Dulles International Airport allows the region, finally, to focus on this reality: a public transit line serving Washington's busiest airport and Virginia's most prosperous -- and congested -- jobs corridor.

But those who live, work or drive near the corridor also must focus on another reality: six years of debilitating construction that will further slow Northern Virginia's busiest thoroughfares. Although some light construction began months ago, the coming weeks and months will bring an entirely new level of din, dust and general havoc to McLean, Vienna, Tysons Corner and beyond.

"There was certainly good news in this because we support the concept of rail," said Rob Jackson of the McLean Citizens Association. "But there are some ugly things here. There's going to be some disruptions. We all wish that there weren't going to be, but there's an understanding that you can't just magically snap your fingers and these projects magically appear."

U.S. Transportation Secretary Ray LaHood sealed the fate of one of the largest transit projects in the country yesterday when he signed an agreement that commits $900 million of federal funds to help build the $5.2 billion Silver Line from northwest Arlington County to Loudoun County.

"If this is not the greatest day for Virginia, then I don't know what is," LaHood said at his agency's headquarters in Southeast Washington. Virginia Gov. Timothy M. Kaine (D), U.S. Rep. Frank R. Wolf (R-Va.), former Virginia Republican senator John W. Warner, Sen. Mark Warner (D-Va.), Democratic Reps. James P. Moran Jr. and Gerald E. Connolly and former representative Tom Davis were among those there to revel in -- and take credit for -- the project's success.

"We in Virginia are fortunate to have Dulles . . . to connect us to the world," Kaine said. "But Dulles can only work and the region can only work if there are transportation options that enable it to be all that it can be. Those options have to include a vigorous road network, but also a very vigorous public transportation network."

The expansion of that network toward the airport will begin in earnest in the next week or two. The Silver Line will extend 23 miles from the East Falls Church Metro station to the airport and will terminate in Ashburn. The tracks will branch off the Orange Line, follow the median of the Dulles Connector Road, trundle through Tysons Corner and then settle into the median of the Dulles Access Road for the bulk of the westward journey.

Through Tysons, trains will travel along an aerial track supported by piers. Huge flyovers will carry the tracks from highway medians onto local roads. A tunnel about 2,000 feet long will carry trains underneath Tysons' main intersection at routes 7 and 123.

To put it all in place, an enormous assemblage of cranes, heavy equipment and construction crews will become visible along the route of the project's first phase, which will extend to Wiehle Avenue in Reston. That phase is scheduled for completion by 2013, with the remainder to be done two years later.

Pile-driving and drilling will begin for the piers to support overhead tracks, some of which, at the Capitol Beltway and Route 123, will rise 55 feet. Excavation of the tunnel will require large staging areas at either end. And lane closures and shifts along routes 123 and 7 will grow in number and duration -- on top of the disruption stemming from the nearby construction of high-occupancy toll lanes on the Beltway.

"People are going to see lots of work going on, not only on 123 and 7, but along the Dulles Connector Road and in the median of the Dulles Access Road," said Marcia McAllister, a project spokeswoman.

Project boosters say the short-term pain will be worth it. The rail line is projected to carry as many as 60,000 riders a day, providing a major commuting alternative for the thousands of drivers who take the jammed Dulles Toll Road from their homes in Reston, Herndon and the outer suburbs to jobs in Tysons Corner and the District.

"This project is going to make a huge difference in helping to ease traffic congestion in our region and improve the quality of life for thousands of Northern Virginians," Wolf said.

The efforts of Wolf, Kaine, Warner and former transportation secretary Mary Peters were crucial last year after it became clear that the Federal Transit Administration, citing costs, schedule overruns and poor management, was inclined to reject Virginia's application for federal assistance. The Bush administration's transportation team reversed itself in December.

The Silver Line's aerial configuration through Tysons continues to trouble detractors who pressed for a tunnel; one grass-roots organization, Tysonstunnel.org, announced yesterday that it is still exploring legal options to encourage competitive bidding on a tunnel.

Regulators and politicians said a tunnel would have been prohibitively expensive and would have set the regulatory process back at least a year, imperiling the project. They say there is no possibility now for a change in plans.