The Architect of the Capitol is charged by law with the care and maintenance of the Capitol Grounds and with any changes and improvements made to them. The Capitol Grounds, as defined by 40 U.S.C 193a, are comprised of approximately 222 acres on which the Capitol, Senate and House Office Buildings and the Capitol Power Plant reside. This area includes lawns, parks, trees, landscaping, horticultural display beds, plazas, terraces, reflecting pools, courtyards, roof gardens, child care center playgrounds, and atria; these areas are equipped with fountains, drinking fountains, outdoor seating, decorative stone retaining walls, lighting, an irrigation systems, streets, sidewalks, and parking areas which are all maintained under this appropriation. The Capitol Grounds are maintained collaboratively by five in-house crews: the Gardening Division, the Plumbing Branch, the Tree Care Branch, the Masonry Branch, and the Trash and Materials Handling Branch.