(1) Barricades and Lighting. Adequate barricades and warning lights shall be so placed as to protect the public from hazard.

(2) Public Convenience. Streets and alleys shall be opened in the manner which will cause the least inconvenience to the public and admit the uninterrupted passage of water along the gutter on the street.

(3) Pipe Bed. Immediately prior to installing the pipe, the trench bottom shall be accurately shaped and graded by hand and bell holes shall be excavated so that the pipe will have uniform contact with a longitudinal bearing on undisturbed earth along its entire barrel length. Bell holes shall be excavated by the pipe layer immediately prior to laying the pipe and shall be of such depth that the pipe bell does not come in contact with the bottom of the bell hole. All sewer pipe shall be laid with the bell end upgrade. Where the floor of the trench at the proper grade is of hard or rock material, the floor shall be excavated four inches or more below grade and backfilled with fine gravel or material approved by the superintendent. Where the floor of the trench at the proper grade is of unstable material the same treatment as described above shall be provided.

(4) Backfill. All sewer pipe shall be provided with adequate bottom and lateral support by thoroughly, carefully and adequately tamping and ramming suitable and proper backfill material beneath, around and to the top of the pipe between the bell holes and sewer joints. All material used for pipe embedment and tamped backfill shall be free of stones, sticks, large clods, lumps of earth, debris, or similar material. When backfill is made in and across a roadway ditch or other watercourse it shall be protected from surface erosion by adequate means. Backfill shall be made with dirt and tamped by hand to a depth of six inches over the pipe. The remainder of the trench shall be backfilled and tamped with gravel or materials approved by the superintendent. All excess dirt will be removed immediately and before the connection is approved by the superintendent.

(5) Restoration of Public Property. Streets, sidewalks, parkways and other public property disturbed in the course of the work shall be restored in a manner satisfactory to the city, at the expense of the property owner.

(6) Completion by the City. Should any excavation in any street or alley be left open or unfinished, for a period of 24 hours or should the work be improperly done, the superintendent shall have the right to finish or correct such work and the expense shall be charged to the property owner. [Code 1975 § 3-3.0114.]