The Dulles Corridor Metrorail Project, informally dubbed the Silver Line due to its color on maps, is a planned extension of the Washington Metro rapid transit system, consisting of 29 stations from Route 772 in Loudoun County, Virginia, to Stadium-Armory in Washington, D.C., United States. The current plan calls for stations in Loudoun, Fairfax, and Arlington counties in Virginia, and the District of Columbia. Eighteen stations will be shared with the Orange Line, including all thirteen shared between the Orange and Blue Lines from Rosslyn to Stadium-Armory.
The Silver Line has two primary goals. The first is to link the District of Columbia by rail to Washington Dulles International Airport and the edge cities of Tysons Corner, Reston, Herndon, and Ashburn. The second is to spur urban development in Tysons Corner and reduce overall reliance on vehicle traffic in the business district, Virginia's largest and the 12th-largest in the nation. This will be a great challenge for an area that is comparable in size to downtown Washington, D.C., but is rather insulated from its surrounding neighborhoods and has no existing grid pattern in its streets.
The Silver Line would also improve public access to the Udvar-Hazy Center, an annex of National Air and Space Museum located near Dulles Airport; Virginia Regional Transit runs a shuttle bus from the Airport to Udvar-Hazy.
Unlike all prior segments of the Metrorail system, which were designed and constructed by the Washington Metropolitan Area Transportation Authority (WMATA), this line will be designed and constructed by the Metropolitan Washington Airports Authority and operated by WMATA. The first phase of the project is funded 43% by $900 million of federal funding, 28% by a special tax district on commercial property proximate to the Silver Line route, and 28% by a $0.50 toll increase on the Dulles Toll Road. Funding for the second phase of the project will be shared by Loudoun County, Fairfax County, the Commonwealth of Virginia, and the Metropolitan Washington Airports Authority.
The federal government which, before Congress created the Metropolitan Washington Airports Authority, owned and operated Dulles Airport built the Dulles Access Road in the 1960s to connect the airport to Washington by way of Interstate 66. The government opted, as the access road was built, to reserve the median of the road for some form of rail transit.
Local residents and officials had talked of a Metro extension to Dulles since the Washington Metro began service in 1976, but a significant plan only developed in 2000. The Dulles Corridor Rapid Transit Project "scoping" process began in April 2000 with a series of meetings with local and federal officials, designed to collect the necessary authorities for the project. Local and federal law required extensive analysis of alternatives – the two most likely being bus lanes or inaction – and of the environmental impact. The rail-only line won over the other alternatives. Initial environmental hearings, which closed on August 28, 2002, were positive. The project received formal approval on June 10, 2004. Although construction was set to begin in 2005, delays in funding have pushed back the start date for construction.
The extension will run in its own right-of-way on a route similar to that of the Dulles Access Road, running above ground both at grade and via aerial structure. The only significant diversions from the access road route are for the stops in Tysons Corner and at Dulles International Airport, where the Metro will alternate between subway and elevated track to maintain the exclusive right-of-way.
Service on the Silver Line is expected to begin in 2013 between Wiehle Avenue and Stadium-Armory, with five new stations being added to the existing network west of East Falls Church. The full line to Route 772, including a station at Dulles International Airport, is expected to be completed in 2016. There will also be a provision made for a future in-fill station at Wolf Trap, between Wiehle Avenue and Tysons West.
There has been controversy over the contract between the Metropolitan Washington Airports Authority and the contractor, Dulles Transit Partners, which consists of Bechtel and Washington Group International. The $2.7 billion project is part of the Virginia Public-Private Partnership; however, it has not been subject to competitive bidding, and there is no upper cap on its cost. The state of Virginia has not made details of the contract publicly available. The contract provides for price escalation of $3 million to $6 million a month for delays.
The method of construction through the Tysons Corner area generated much debate. In the end, however, plans were made to build the extension above ground. Early plans called for a tunnel running from before Tysons East to beyond Tysons West with all four stations in between being below ground. When the contractor hired to design the Silver Line—a consortium of Bechtel and Washington Group International—found the costs to be too high, the design was changed to use a short tunnel only between Tysons 123 and Tysons 7 stations (underneath higher ground)with all four stations being at or above ground. In March 2006, the contractor was ordered to examine an alternative "large bore" tunnel digging technique (successfully used in Europe) with the potential to lower costs of a tunnel through the entire Tysons section. The contractor found that there would not be a significant cost reduction and proposed staying with the short tunnel option. In April 2006, the long tunnel concept was revived after allegations that the design contractor had inflated costs for the tunnel in order to avoid sharing the job with an outside tunneling contractor. The allegations led to calls for an outside cost estimate to determine more realistic tunnel costs.
On May 15, 2006, Virginia Transportation Secretary Pierce R. Homer announced the creation of an advisory panel headed by the American Society of Civil Engineers. The panel had about two months to evaluate options for completing the line through Tysons Corner, with the results presented to the state on July 27, 2006 and published on July 31, 2006. On September 6, 2006, Virginia Governor Tim Kaine announced his decision in favor of an elevated track through Tysons Corner. In his statement, Kaine said he believed a tunnel would be the best option, but decided against it, citing a fear of losing federal funding for the project. However, Virginia has until May 2008 to submit their final proposal to the Federal Transit Administration (FTA).
The tunnel controversy, however, is not over. Shortly after Governor Kaine's decision, the Greater McLean Chamber of Commerce formed a coalition of tunnel supporters and put forth a technical proposal to help revive consideration of building a tunnel through Tysons Corner. The Virginia Department of Rail and Public Transportation hired an independent consultant to assess the coalition's proposal. The consultant's report—sent on March 7, 2007, to Secretary Homer—stated, however, that "[t]here is a significant risk that the project cost of a Large Bore Tunnel would not meet the FTA's cost effectiveness ratio criteria, which could compromise federal funding for the project.
On November 26, 2007, Tysons Tunnel, Inc. filed a lawsuit against the United States Department of Transportation and the FTA in the Eastern District of Virginia challenging the denial of their petition to reopen and consider additional evidence regarding the benefits of a tunnel over the aerial option. Gary Baise, the Republican challenger to Gerry Connolly's Fairfax County's Board of Supervisor's Chairmanship, represents Tysons Tunnel. Start of construction has been delayed as approval of the $900 million federal contribution to project costs awaits the conclusion of a review by FTA of the proposal submitted by Virginia.
On January 24, 2008, Virginia government representatives including Governor Tim Kaine and Senators John Warner (R) and Jim Webb (D) arrived at the FTA to address last minute concerns by FTA staff and administrators. FTA Administrator James Simpson presented Governor Kaine with a letter which included stark criticisms with the project as presented. The project as presented was given a "Medium-Low" rating (projects must receive a "Medium" or higher rating to be approved under the Federal New Starts Funds project) and was ineligible to receive the $900 million in federal funding. FTA's concerns included the Metropolitan Washington Airports Authority's inexperience in large design-build contracts, an exaggeration of funding numbers from the Dulles Toll Road, and an inability for Metro to maintain the 23 mile line once it had been built. Virginia leaders vowed to address the concerns by Monday, January 28, 2008, as several fixed priced contracts for building materials costs were due to expire on February 1. Governor Kaine requested an extension of the deadline to February 1, which was granted by the FTA.
On April 30, 2008, the FTA reversed the earlier decision and approved the project, saying that it met standards for cost efficiency, construction and ridership and moving it closer to receiving the $900 million in federal funding. Officials told The Washington Post that the project would move into the final design stage.