D.C. Code § 10-511.01: Tunnel under Capitol Grounds and Botanic Garden grounds — Required.

The Mayor of the District of Columbia is authorized and directed, in constructing, maintaining, and operating a vehicular tunnel in the City of Washington, District of Columbia, extending from the vicinity of 2nd and C Streets Southwest, to the vicinity of 3rd and Constitution Avenue Northwest, as a part of the Innerloop Freeway System, to locate a portion of such tunnel under square W-576, which is a part of the United States Botanic Garden grounds, and reservation 12, which is a part of the United States Capitol Grounds.