The department shall have the power and authority to adopt and amend all rules and regulations necessary to carry out the provisions of sections 39-891 to 39-8,122; Provided, that such rules and regulations shall not violate any law of the State of Nebraska, or any law, code, rule, or regulation of the United States, pertaining to or affecting interstate bridges.
Neb. Rev. Stat. §§ 39-8,120