Throughout the length of the sewerage system, there have been provided Y's and one- eighth bends, duly marked by one by two-inch scantling which extend to within about twelve inches of the surface of the ground. The Assistant Service Director shall ascertain the exact location of these Y's which are definitely recorded in the office of the Clerk of Council. Care shall be exercised in making house connections when removing the stopper in the one-eighth bend to prevent the breakage of the bell of the same.