Four teams of contractors and investors have been named to a short-list of companies that will be considered under a public-private partnership with Maryland to build the Purple Line.

The teams were selected from a pool of six respondents to an initial request for qualifications that the state put out in early December.

The 16-mile Purple Line will connect with Washington's metro system and include 21 stations between Bethesda in Montgomery County and New Carrollton in Prince George's County.

Transportation Secretary James Smith said in a statement that the teams selected "clearly demonstrated their qualifications to deliver this important project."

They will now have to "submit proposals to design, build, construct, finance, operate and maintain" the project, the state said.

The finalist teams are:

•Maryland Purple Line Partners, composed of Vinci Concessions, Walsh Investors, InfraRed Capital Partners, Alstom Transport and Keolis;

•Maryland Transit Connectors, composed of John Laing, Kiewit Development Co. and Edgemoor Infrastructure;

•Purple Line Transit Partners, composed of Meridiam Infrastructure, Fluor Enterprises and Star America Fund;

•Purple Plus Alliance, composed of Macquarie Capital and Skanska Infrastructure Development.

Under the public-private partnership, or P3, the private sector partner is expected to invest between $500 million and $900 million of the total $2.2 billion cost, according to the Maryland Transit Administration.

The private partner will also be responsible for long-term operations and maintenance.

Robert Smith, administrator of the MTA, said he was "quite pleased" with the selections.

"The interest expressed by so many well-regarded companies is a testament to both the value of the Purple Line as a transportation asset and the power of public-private partnership to deliver value for citizens over a long period," he said in a statement.

The state will select a private sector partner late this year or early next year, and construction could begin as early as spring 2015, the MTA said.

krector@baltsun.com

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