A $10 billion planned expansion of Union Station in Washington, D.C., could increase passenger capacity three-fold. Beyer Blinder Belle and Grimshaw Architects will work together over the next few years to determine how best to preserve some historical aspects of the station while making it more efficient. Meanwhile, Akridge, a real estate firm that is one of the station’s managers, plans to add 3 million square feet of development above the tracks behind the station. Read The Washington Post/Digger blog here