17 Del. C. § 178

In connection with the development of any controlled-access facility, the Department may plan, designate, establish, use, regulate, alter, improve, maintain and vacate local service roads and streets or may designate as local service roads and streets any existing road or street and may exercise jurisdiction over service roads in the same manner as is authorized over controlled-access facilities under the terms of this subchapter, if, in their opinion, such local service roads and streets are necessary or desirable. Such local service roads or streets shall be of appropriate design, and shall be separated from the controlled-access facility proper by means of all devices designated as necessary or desirable by the proper authority.