Streets and Highways Code § 30151
ARTICLE 4. General Powers and Duties of the Department of Transportation
No part of any additional transportation facilities authorized, however, shall be constructed or operated by the commission, or by any person or public or private corporation, within any county or city, unless and until the route thereof within the county or city has been approved by the board of supervisors, city council, or other legislative body thereof, as the case may be, notwithstanding any other provision in this chapter.