D.C. Code § 43-105

It shall be the duty of the owner or owners of any cemetery or cemeteries in the District to inclose such cemetery or cemeteries with good and sufficient walls or fences to prevent entrance thereto or exit therefrom except by gates provided for that purpose. Such cemetery or cemeteries shall, if required by the Mayor of said District, be underdrained to such a depth as will prevent water remaining in any grave or vault therein.