Six teams of private companies have begun to compete for a long-term contract to design, build, operate and help pay for a light-rail Purple Line in the Maryland suburbs, state officials said Wednesday.

The companies met a deadline Tuesday to submit a “Statement of Qualifications” detailing their ability to carry out such a contract on a 16-mile rail line planned between Montgomery and Prince George’s counties.

Maryland Department of Transportation officials said they plan to narrow the group to four or fewer teams that will be invited to submit detailed proposals. That “short list” is to be announced early next month.

Those teams will have to submit their detailed proposals by next fall, and one will be selected late next year or early 2015, officials said. If the project is awarded federal aid, Maryland officials hope to begin construction in spring 2015 and open the line between Bethesda and New Carrollton in 2020.

The deadline for companies to enter the competition came one month after the state’s Board of Public Works approved a public-private partnership for a Purple Line. The contract, which would probably span 35 to 40 years, could be worth more than $6 billion.

It also would be the first public-private partnership for a Maryland transit project. Maryland officials say the winning team will be asked to contribute $400 million to $900 million toward construction. The state would then pay the team annually to operate and maintain the line based on certain performance standards.

The private teams represent local, national and international firms, officials said. Three of the teams are: Plenary Group USA and Bechtel Development Co.; VINCI Concessions, Walsh Investors, InfraRed Capital Partners, Alstom Transport, and Keolis S.A.; and John Laing Investments, Kiewit Development, and Edgemoor Infrastructure & Real Estate.

The other three are: CSCEC and United Labor Life Insurance; Meridiam Infrastructure Purple Line, Fluor Enterprises, and Star America Fund GP; and Macquarie Capital Group and Skanska Infrastructure Development.

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