R309-550-8. Installation of Water Mains

  (1) Standards.

  The specifications shall incorporate the provisions of the manufacturer's recommended installation procedures or the following applicable standards:

  (a) For ductile iron pipe, AWWA Standard C600-10, Installation of Ductile Iron Water Mains and Their Appurtenances;

  (b) For PVC pipe, ASTM D2774, Recommended Practice for Underground Installation of Thermoplastic Pressure Piping and PVC Pipe and AWWA Manual of Practice M23, 2003;

  (c) For HDPE pipe, ASTM D2774, Recommended Practice for Underground Installation of Thermoplastic Pressure Piping and AWWA Manual of Practice M55, 2006; and,

  (d) For Steel pipe, AWWA Standard C604-11, Installation of Buried Steel Water Pipe- 4 inch and Larger.

  (2) Bedding.

  A continuous and uniform bedding shall be provided in the trench for all buried pipe. Stones larger than the backfill materials described below shall be removed for a depth of at least 6 inches below the bottom of the pipe.

  (3) Backfill.

  Backfill material shall be tamped in layers around the pipe and to a sufficient height above the pipe to adequately support and protect the pipe. The material and backfill zones shall be as specified by the standards referenced in Subsection (1), above. As a minimum:

  (a) for plastic pipe, backfill material with a maximum particle size of 3/4 inch shall be used to surround the pipe; and,

  (b) for ductile iron pipe, backfill material shall contain no stones larger than 2 inches.

  (4) Dropping Pipe into Trench.

  Under no circumstances shall the pipe or accessories be dropped into the trench.

  (5) Burial Cover.

  All water mains shall be covered with sufficient earth or other insulation to prevent freezing, unless they are part of a non-community system that can be shut-down and drained during winter months when temperatures are below freezing.

  (6) Thrust Blocking.

  All tees, bends, plugs, and hydrants shall be provided with thrust blocking, anchoring, tie rods, or restraint joints designed to prevent movement. Restraints shall be sized to withstand the forces experienced.

  (7) Pressure and Leakage Testing.

  All types of installed pipe shall be pressure tested and leakage tested in accordance with AWWA Standard C600-10.

  (8) Surface Water Crossings.

  (a) Above Water Crossings

  The pipe shall be adequately supported and anchored, protected from damage and freezing, and accessible for repair or replacement.

  (b) Underwater Crossings

  (i) A minimum cover of 2 feet or greater, as local conditions may dictate, shall be provided over the pipe.

  (ii) When crossing water courses that are greater than 15 feet in width, the following shall be provided:

  (A) Pipe with joints shall be of special construction, having restrained joints for joints within the surface water course and flexible restrained joints at both edges of the water course.

  (B) Isolating valves shall be provided on both sides of the water crossing at locations not subject to high ground water or flooding, so that the section can be isolated for testing or repair.

  (C) A means shall be provided, such as a sampling tap, not subject to flooding, to allow for representative water quality testing on the upstream and downstream side of the crossing.

  (D) A means shall be provided to pressure test the underground water crossing pipe.

  (9) Sealing Pipe Ends During Construction.

  The open ends of all pipelines under construction shall be covered and effectively sealed at the end of the day's work.

  (10) Disinfecting Water Lines.

  All new water mains or appurtenances shall be disinfected in accordance with AWWA Standard C651-05 or a method approved by the Director. The specifications shall include detailed procedures for the adequate flushing, disinfection and microbiological testing of all water mains. On all new and extensive distribution system construction, evidence of satisfactory disinfection shall be provided to the Division. Samples for coliform analyses shall be collected after disinfection is complete and the system is refilled with drinking water. A standard heterotrophic plate count is advisable. The use of water for public drinking water purposes shall not commence until the bacteriologic tests indicate the water is free from contamination.