Del. Code tit. 2 § 945
Each political subdivision, acting jointly with another, pursuant to this chapter, may enact, concurrently with the other political subdivisions involved, such ordinances as are provided for by subdivision (2) of § 909 of this title, and to fix by such ordinances penalties for the violation thereof, which ordinances, when so concurrently adopted, shall have the same force and effect within the political subdivisions and on any property jointly controlled by them or adjacent thereto, whether within or without the territorial limits of either or any of them, as ordinances of each political subdivision involved, and may be enforced in any one of the political subdivisions in like manner as are its individual ordinances. The consent of the Department of Transportation to any such ordinance, where the State is a party to the joint venture, shall be equivalent to the enactment of the ordinance by a political subdivision. The publication provided for in subdivision (2) of § 909 of this title, shall be made in each political subdivision involved in the manner provided by law or charter for publication of its individual ordinances.
2 Del. C. § 945