It 's biggest federal building project in DC area since Pentagon 200 years ago . Complex to be on top of historic buildings in long - time part of Washington Project to gather more than 15,000 employees now scattered in federal offices . First new building : President Franklin Roosevelt planned the defense consolidation , Lieberman said , because he knew war was imminent and felt it could be coordinated more efficiently from one location . Coast Guard headquarters , costing about $ 435 million .
It 's biggest federal building project in DC area since Pentagon 200 years ago . Complex to be on top of historic buildings in long - time part of Washington Project to gather more than 15,000 employees now scattered in federal offices . First new building : Coast Guard headquarters , costing about $ 435 million .