All service pipes used underground shall be of cast iron, galvanized steel, tin lined copper, laid not less than three feet (3') below the grade and of sufficient strength to withstand the water pressure; and all such work, alterations or extensions thereof, together with the size of the pipe, must be to the acceptance of the Superintendent. No extension of service pipes shall be made without first obtaining a permit therefor from the Superintendent, and no service pipe less than one inch (1") in diameter shall be connected with the water mains at the junction of any street in the City. (1990 Code § 3.04.080; amd. 2003 Code)