Maryland's planned light-rail projects. (The Washington Post)

A proposed light-rail Purple Line project has been recommended for $100 million in federal money in the next fiscal year as part of President Obama’s budget released Tuesday, marking a critical financial milestone for what would be the Maryland suburbs’ first direct rail link.

Just as significant to the project’s future is that the Purple Line was included on a list of seven large transit projects nationwide that the Federal Transit Administration recommends for a “full funding grant agreement,” a ­longer-term commitment by the federal government to help pay for the project’s construction.

The total amount of federal funding recommended for a Purple Line will be released Wednesday, federal officials said. Maryland transit officials are seeking $900 million in federal grants for the project’s $2.2 billion construction costs. The $100 million included in the president’s budget would be allocated in the federal fiscal year that begins Oct. 1.

“This is really good news,” said Rep. Donna Edwards (D-Md.), whose district includes part of the proposed Purple Line route in Prince George’s County. “This really keeps the Purple Line on the trajectory we need.”

The 16-mile light-rail line would have 21 stations from Bethesda in Montgomery County to New Carrollton in Prince George’s. Maryland transit officials have said they hope to begin construction in 2015 and begin service in 2020.

“It’s absolutely fundamental,” Ralph Bennett, president of the Purple Line NOW advocacy group, said of the federal funding. “It means the feds are in for their first major piece of their share. . . . This is just a fantastically positive sign.”

The Purple Line still needs federal environmental approval, which would allow the Maryland Transit Administration to begin condemning private property needed along the route. Building the line would require condemning 116 homes and businesses, according to the state’s environmental impact study.

Maryland transit officials say the Purple Line is needed to directly connect the state’s spokes of the Metrorail system with MARC commuter rail and Amtrak stations. It would provide faster, more reliable transit between suburbs than buses and would spur new investment around stations in older suburbs, state officials have said.

Opponents say that the state has not adequately considered the environmental destruction a rail line’s construction would cause, including cutting hundreds of trees along a popular wooded trail between Bethesda and Silver Spring. Others say state plans would not do enough to reduce train noise and vibrations along the route.

The project’s momentum could be slowed by litigation. The Town of Chevy Chase, whose leaders object to the current Purple Line proposal, recently approved $350,000 to hire a Washington law firm to provide legal advice and lobby Congress and the federal government.

Some environmentalists also have said they are considering a lawsuit, arguing that the Purple Line plans do not properly consider potential impacts on a crustacean called the Hay’s Spring amphipod, which is listed as an endangered species.

Ajay Bhatt, president of the Friends of the Capital Crescent Trail, which opposes the project, said he was “disappointed” that federal funding would come through before such concerns have been addressed.

“Many things need to be analyzed before the federal and state governments spend billions of dollars,” Bhatt said.

Obama’s budget also includes $102 million in fiscal 2015 for construction of Metro’s new Silver Line in Northern Virginia, an amount already determined in that project’s federal funding agreement. An additional $150 million would be allotted to Metro as annual federal matching funds for a 10-year, $3 billion program to improve Metrorail’s safety and reliability.

And the budget also includes $100 million to help build a planned 14-mile light-rail Red Line in Baltimore. That project is estimated to cost $2.6 billion.

The federal money isn’t a certainty. The multiyear “full funding grant agreement” spelling out how much federal money the state would receive annually must still be negotiated. Those allotments would then be subject to annual appropriations from Congress.

But the timing of the news that the Purple Line is officially being considered for a longer-term funding agreement was critical. The Maryland Transit Administration recently began pursuing private investors to help pay for another considerable chunk of the project’s construction, up to another $900 million. Wall Street investors eyeing the project now have more certainty that the federal aid will materialize.

The private investors are being pursued as four teams of private companies bid on a public-private partnership to design, build, operate, maintain and help finance a Purple Line. Such a contract would span 30 to 35 years. With an estimated value of more than $6 billion, it would be one of the largest government contracts ever in Maryland as well as one of the broadest public-private partnerships for a U.S. transit project.

The state’s Purple Line schedule calls for selecting a private partner by spring 2015, about the time that the state would finalize a federal funding agreement. That timing would allow construction to begin on schedule later in 2015.

The announcement of federal funding “gives risk managers for the [public-private partnerships] a much higher level of comfort about the viability of the project,” Bennett said.

The line would have 21 stations, including in Bethesda, Silver Spring, College Park, Langley Park, Riverdale Park and New Carrollton. Two-car trains would run mostly above ground, along local streets.

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