A train arrives at the Ronald Reagan Washington National Airport Metro Station. (Matt McClain/FOR THE WASHINGTON POST)

Metro’s board of directors Thursday all but finished its budget process for the next fiscal year as a key committee approved a $1.14 billion spending plan for capital improvements, including the purchase of new rail cars and buses and the redesigning of some of the transit system’s most crowded subway stations.

Added to the agency’s recently adopted $1.7 billion operating budget, the capital-improvement budget would put Metro spending at close to $3 billion in the 12 months beginning July 1. The overall budget includes a new fare structure that will increase the average cost of a subway ride by 10 cents, to $3.

The capital-spending plan was approved Thursday by the board’s finance committee. Because the committee is made up of the full board, the unanimous vote was tantamount to final approval. The members are expected to give that final approval later this month when they convene as a board rather than a committee.

Last year, Metro unveiled a long-term plan for the transit system’s projected growth through 2025. General Manager Richard Sarles described the $1.14 billion capital budget for fiscal 2015 as “the first downpayment” toward the immense cost of achieving the goals outlined in that decade-long strategic plan.

Among other changes, the long-term plan, dubbed “Metro 2025,” envisions major station improvements, a large expansion of the Metrobus fleet, an overhaul of subway tracks and a new generation of rail cars replacing hundreds of cars now in service. In setting Metro on course to fulfilling that plan, officials said, the capital-improvement budget will do more to shape the agency’s future than any capital budget in years.

In the next fiscal year, for example, Metro plans to acquire 64 new rails cars, part of what is called the 7000 series, and put them all into service.

Over time, the agency plans to buy 748 of the cars, which include digital information displays and an array of cutting-edge safety and operational features lacking in the current fleet. With the retirement of many older cars, Metro said, the new cars, by 2018, will make up half the agency’s inventory of rail cars.

Under the Metro 2025 plan, the agency eventually would cease running six-car trains and would run eight-car trains only. Toward that end, officials said, the capital-improvement budget includes money for upgrading the system’s tracks and the electrical system needed to run exclusively eight-car trains.

Metro also plans to buy 101 new “low-floor” buses in the coming fiscal year and 150 new vehicles for the MetroAccess shuttle service, used by people who are unable to ride buses or subway trains because of their disabilities.

As for station improvements envisioned by Metro 2025, the capital budget sets aside money for designing major renovations to the underground stops at Union Station and the L’Enfant Plaza and Gallery Place-Chinatown stations, all in the core of Washington.

At L’Enfant Plaza, where overlapping Orange-Blue and Green-Yellow stretches meet, the mezzanines and platforms are too small for the crowds. That is also the case at Gallery Place-Chinatown, where Red and Green-Yellow stretches intersect; and at Union Station, where commuter-rail and Amtrak passengers get on and off the Red Line.

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