The franchise (A) to use, for transmitting, conducting and distributing gas within the City of Sebastopol for any and all purposes other than those authorized under Section 19 of Article XI of the Constitution of the State of California as said section existed prior to its amendment on October 10, 1931, all gas mains, pipes, conduits and connections therewith that are now or may hereafter be lawfully placed in the public streets, ways and places within said City, and (B) to construct, maintain and operate in said public streets, ways and places, all mains, pipes, conduits and connections necessary or proper for said purposes, is hereby granted to Pacific Gas and Electric Company, its successors and assigns, for the term of 50 years from and after the effective date of the ordinance codified in this chapter upon the terms and conditions in this chapter prescribed.