With the federal government's formal commitment to an extension of Metrorail to Dulles International Airport, we are about to witness the most significant expansion in the national capital's transportation system since the original Metro lines were laid out. The politicians and planners who struggled for decades to create the new Metro line across Northern Virginia know that. More than a dozen of them grinned in triumph for a photo at the signing ceremony Tuesday as the federal government pledged $900 million for the line through Tysons Corner and out to Reston. But commuters will know it, too, as they drive across construction zones in Northern Virginia from now until 2013. Here's what's happening.
Preparatory work for rail construction began last winter. Ground was cleared along the Interstate 66/Route 267 corridor near the West Falls Church Metro station and along Route 123 in Tysons. Twenty-one utility services along Route 123 and Route 7 are being moved. Route 7 lane shifts have begun. But we haven't seen anything yet.
As construction progresses, Route 7 will be widened to four lanes in each direction and the service roads will disappear. Lanes will shift, and a new median will be created to accommodate the rail line and stations. The Route 7 work is likely to have the highest impact on drivers. Drivers will see many changes over the next year. By Memorial Day, under the current schedule, the ramp configuration from Route 123 to Route 7 will be shifted. Later, the lanes of Route 7 will bulb out away from their current path. That pattern will gradually progress north toward the Dulles Access Road.
The effects will be less dramatic on Route 123, because the rail line and stations will be built on the north side of the roadway rather than in the middle, but the line still must pass over the Capital Beltway and the big cross streets of Tysons.
In the next week or two, rail project crews will begin clearing trees in the median of the Dulles Airport Access Road from Route 7 west to Wiehle Avenue in Reston. Next week, there will be tree clearing along Route 123 near Scotts Crossing Road in McLean.
The rail line will be built almost entirely above ground. Only a 2,100 foot section at the junction of Routes 123 and 7 will be in a tunnel. That's where the grade is too steep to go up and down the natural high point of Fairfax County.
Compared with the construction through Tysons, the rail line's progress out along the Dulles Access Road will be relatively easy. The line will be built down the middle of that highway. Congestion might result from drivers slowing to watch the progress of the work.
In Tysons, meanwhile, some of the construction that motorists see on Route 123 and on Route 7 near the Beltway is part of the High Occupancy Toll lanes project, which will widen the Beltway and create new ramps for the HOT lanes. All this, plus commercial construction within Tysons, will continue for the next few years.