(A)   (1)   The building sewer for all structures other than detached single-family residential units shall be constructed of a size not less than six inches internal diameter, with a minimum slope of one-fourth inch per lineal foot.
      (2)   A four-inch building sewer is permitted only of detached single-family residential units subject to the following conditions:
         (a)   The building sewer from the street sewer to the right-of-way must be six inches;
         (b)   The building sewer from the right-of-way to the structure may be four inches; and
         (c)   Clean outs on four-inch laterals must be provided at all changes in grade or alignment. The maximum span shall be 50 feet between clean outs.
   (B)   The building sewer shall be laid at uniform grade, and in the straightest alignment possible. Prior to the installation, both ends of the building sewer should be exposed and the elevations verified to establish proper grade and to disclose any problems in elevation prior to installation. Changes in direction shall be made only with properly curved pipe and fittings, with all such fittings being less than 45 degrees with at least an 18-inch separation maintained between fittings. The use of 90 degree bends shall not be permitted.
   (C)   The depth shall be sufficient to afford protection from frost.
   (D)   All material and workmanship shall be in strict accord with the Specifications for Sanitary Sewers of the Water and Sewer Department.
   (E)   A minimum of four inches of well-compacted sand or gravel bedding must be provided below the pipe to support it over its full length. If rock is encountered, six inches of bedding must be provided. If the material at or below the normal grade of the bottom of the pipeline is unsuitable for foundation, it shall be removed to such depths and widths as the inspector may direct and be replaced with gravel.
   (F)   The building sewer must be centered in a dry trench of minimum width. The maximum allowable trench width is 30 inches. All excavation shall be kept dry and free of water during installation.
   (G)   (1)   Hand backfill shall be placed and compacted around and over the pipe in six-inch layers to one-foot above the top of the pipe. Sand or an approved granular backfill material shall be required for this purpose.
      (2)   Material for hand backfill should under no circumstances be dumped on the exposed pipe, but should be moved along the trench which then may then be machine backfilled. Backfilled entering the trench must come upon previously placed machine backfill. All excavation in paved areas shall be backfilled with well-compacted sand and gravel, or in accordance with the requirements of the road opening permit, if stricter.
   (H)   (1)   Approved adapters must be used to connect dissimilar pipe sizes or materials between the building sewer and the sewer lateral provided as part of the street improvements, and the building sewer and the house connection. Only acceptable adapters are permitted and no building sewer shall be installed with non-compatible materials. When a connection is made to a sewer lateral, the cap or plug must be cut off and removed.
      (2)   The actual tapping of a connection into the sanitary sewer and the connection at the house shall be performed only in the presence of an inspector.
   (I)   The connection between the interior plumbing and the building sewer shall be made at a point approximately five feet outside the foundation wall.
   (J)   A minimum of one clean out must be provided on the building sewer to permit future maintenance by the property owner, with the maximum spacing between clean outs being 100 feet and one clean out being provided near the structure to be served.
(Ord. 97-104, passed 2-3-1997)  Penalty, see § 50.999