On December 16, 2008 Secretary of the Interior Dirk Kempthorne cut the ribbon opening for the new greenroof that has been planted on the third wing of the Main Interior Building in Washington, D.C. The greenroof is part of an ongoing modernization of the Main Interior Building, to be conducted in six phases. Each phase will correspond to one of the six wings of the building, with a scheduled completion date of 2011 at an estimated cost of $175 million.

“What more suitable place for a green roof than the headquarters of America’s conservation department in Washington, DC?” Secretary Kempthorne asked (ENS, 2008). 20,000 plants were expected to be planted.