The Montgomery County Planning Board has endorsed a light rail system instead of buses for the proposed Purple Line.
The panel also decided Thursday to support placing the 16-mile suburban rail line next to the Georgetown Branch Trail, according to the Washington Post.
The planning board is the county's first public agency to officially take a position on the system. The Montgomery County Council could vote on the plan as soon as Jan. 27.
Light rail would be more expensive than a rapid bus system, but board members say rail would be quieter, better for the environment and capable of carrying more passengers.
Gov. Martin O'Malley is expected to decide next year whether to build a light rail or rapid bus system.