D.C. Code § 10-117
In order to extend Beach Parkway northward to Western Avenue as provided for by the plans of the National Capital Planning Commission for the park system of the District of Columbia and to preserve the flow of water in Rock Creek Park and to extend West Beach Drive to connect Beach Drive and Rock Creek Park with Western Avenue, the Secretary of the Interior is authorized to convey by and on behalf of the United States of America to the owners of parcel 78/5, or to such party or parties as said owner or owners shall designate, the title of the United States in and to a piece of land containing approximately 55,000 square feet at and near the intersection of Western Avenue and West Beach Drive as proposed in accordance with the plan of the permanent system of highways of the District of Columbia, being a part of reservation 339; provided, that the owners of said parcel 78/5 shall furnish the United States of America with a good and sufficient title in fee simple, free of all encumbrances, to that piece of land lying along and east of the center line of West Beach Drive as proposed in accordance with the plan of the permanent system of highways of the District of Columbia, and extending east to the creek immediately north of the present north line of United States reservation 432 and extending north to United States reservation 339 and containing approximately 58,500 square feet; provided further, that the owners of parcel 78/5 dedicate to the District of Columbia for street purposes the west half, 45 feet in width, of West Beach Drive as proposed in accordance with the plan of the permanent system of highways of the District of Columbia, along their property immediately north of the north line of reservation 432.
D.C. Code § 10-117