It is determined upon the basis of an engineering and traffic investigation that the speeds hereinafter set forth upon the following streets or portions thereof would facilitate the orderly movement of vehicular traffic upon the streets hereinafter set forth. Accordingly, the prima facie speed limits are set forth upon such streets or portions thereof as follows.
(Ord. 3027 § 2; Ord. 3044 § 1; Ord. 3060 § 1; Ord. 3063 § 2)