The Denver Regional Transportation District’s (RTD) Eagle P3 project, which comprises three commuter rail lines and a commuter rail maintenance facility, reached the halfway-to-completion point.

The three lines are the East Rail Line to Denver International Airport (DIA), the Gold Line to Arvada and Wheat Ridge, and the first segment of the Northwest Rail Line to south Westminster.

The three lines and the maintenance facility will open in 2016.

The Eagle P3 project is the nation’s first full public-private partnership for transit. Local RTD taxes combine with a $1.03 billion federal grant and $450 million from Denver Transit Partners, the 34-year concessionaire that will build, operate and maintain the trains, to make up the $2.2 billion project.

In addition to East and Gold, Eagle is building the first six-mile segment of Northwest Rail Line to Westminster. That became possible because the first four miles are shared with the Gold Line. In all, the project will add 36 miles of rail service to the metro area.

FasTracks is RTD’s voter-approved transit expansion program to build 122 miles of commuter rail and light rail, 18 miles of bus rapid transit service, add 21,000 new parking spaces, redevelop Denver Union Station and redirect bus service to better connect the eight-county district.