All excavation for sewers shall be by open cut from the surface. The sides of the trench shall be substantially vertical, using such sheeting and bracing as may be necessary to accomplish this result. The trench shall be excavated two inches below the required grade for the bottom of the pipe barrel and refilled to the proper grade with pea gravel, sand or stone not over ¾-inch in diameter. The width of the trench at the top of the pipe shall not exceed two feet plus the outside diameter of the pipe.
(Ord. 1049, passed 8-13-63)