§ 15-153 SEWAGE COLLECTION AND DISPOSAL SYSTEMS.
   1.   In accordance with the standards and specifications of these and other applicable regulations, the subdivider shall install sanitary sewers whenever a sanitary sewer system is reasonably accessible, as determined by the city’s code of ordinances or the Planning Commission. If a public sanitary sewer is placed in a street or alley abutting any property, the owner thereof shall be required to connect to said sewer for the purpose of waste disposal, and it shall be unlawful for any such owner or occupant to maintain upon any such property an individual sewage disposal system, consistent with the code of ordinances of the city.
   2.   Whenever a sanitary sewer is not reasonably accessible, septic tanks or other unit disposal systems may be used; provided, that, such systems comply with the requirements of the State Department of Environmental Quality and are not located within 20 feet of the lot line of the lot on which the system is located. Where sanitary sewer systems are not reasonably accessible and will not become available for a period in excess of five years, the applicant may install sewage systems as follows.
      a.   Medium-density residential districts. Central sewerage system only; no individual disposal systems will be permitted. Where plans exist for a public sewer system to be built in a greater period than five years, the applicant shall install all sewer lines, laterals and mains to be in permanent conformance with such plans and ready for connection to such public sewer main.
      b.   Low-density residential districts. Individual disposal systems or central sewerage systems may be used; however, easements for future use shall be included on the final plat.
   3.   All sanitary sewer improvements shall be designed by an engineer registered in the state and shall be approved by the City Council, the Planning Commission, the State Department of Environmental Quality and other appropriate agencies. Sanitary sewer design shall be in accordance with the design criteria for sanitary sewers in this article. In no case shall the use of flexible PVC pipe or any rigid plastic pipe with a wall thickness and strength of less than SDR 35 be allowed. Locator wires shall be placed at all main connections.
   4.   When required, or proposed sanitary sewer improvements correspond with recommended improvements contained in the city’s comprehensive plan (or other approved sanitary sewer report or document), said facility shall be designed in accordance with said plan or report.
   5.   When an improvement required by the comprehensive plan (or other approved sanitary sewer report or document), exceeds the capacity needed to serve the proposed development, the city may participate in the excess cost of such facility, in accordance with said city’s adopted utility extension policies.
   6.   In low and medium density residential districts, where a public sanitary sewerage system is reasonably accessible, and will become available within a reasonable time (not to exceed five years), the developer may choose one of the following alternatives.
      a.   Central sewerage system. (Maintenance cost to be assessed against each property benefitted.) Where plans for future public sanitary sewerage systems exist, the developer shall install the sewer lines, laterals and mains to be in permanent conformance with such plans and ready for connection to such public sewer mains.
      b.   Individual disposal systems. The developer shall install sanitary sewer lines, laterals and mains from the easement or alley to a point in the subdivision boundary where a future connection with the public sewer main shall be made, in addition to allowing the use of individual systems on each site. As a condition of building permit approval on each housing unit in such an area, sewer lines shall be placed from the house to the street lines, and a connection shall be available in the home to connect from the individual disposal system to the sewer system when the public sewers become available. Such sewer systems shall be capped until ready for use and shall conform to all plans for installation of the public sewer system, where such exist, and shall be ready for connection to such public sewer main.
   7.   Sewage collection and disposal systems in high density residential and nonresidential districts shall connect with public sanitary sewerage systems. Sewers shall be installed to serve each lot and to grades and sizes required by local officials and approving agencies. No individual disposal systems or treatment plants (private or group disposal systems) shall be permitted. Sanitary sewerage facilities (including the installation of laterals in the right-of-way) shall at all times be subject to the specifications, rules, regulations and guidelines of the city and the State Department of Environmental Quality.
   8.   If public sewer facilities are not available and individual disposal systems are proposed, minimum lot areas shall conform to the requirements of the zoning ordinance, and percolation tests and test holes shall be made as directed by the Municipal Building Inspector and the results submitted to the State Department of Environmental Quality. The individual disposal system, including the size of the septic tanks and size of the tile fields or other secondary treatment devices, shall also be approved by the Municipal Building Inspector, and be in accordance with state statutes.