Delaware Code
Subchapter III. Jurisdiction, Powers and Duties of Department
§ 141. Regulation of traffic; exceptions.

(a) The Department shall have jurisdiction and control of all state highways of this State outside of the limits of incorporated cities and towns for the purpose of regulating traffic and for the use and operation of all vehicles thereover, and may adopt any and all rules and regulations respecting the use of such highways and the operation of all vehicles upon the same.
(b) Each rule and regulation adopted pursuant to this section shall be in the form of a resolution signed by the Secretary or the Secretary's designee. A permanent record of these shall be kept by the Department and at the time of adoption a copy of each shall be forwarded to the Department of Safety and Homeland Security and to the New Castle County police, if within their jurisdiction.
(c) Pursuant to this section, the Department is authorized to perform all engineering studies and traffic investigations necessary to implement this section and Chapter 41 of Title 21, and to install, maintain, operate and remove all traffic control devices necessary to implement Chapter 41 of Title 21 and regulations adopted thereunder.
(d) The Department, on the basis of engineering studies and traffic investigations, may prohibit the operation of trucks or other commercial vehicles or impose limitations as to the weight thereof on designated highways which prohibitions and limitations shall be posted as set forth in § 4505 of Title 21.
(e) Nothing in this section shall be construed as granting the Department the power to make any rules and regulations respecting the use of highways contrary to Delaware law.

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