III. Standards of Design and Construction
1. General
A. The design and construction of the utility's water or wastewater system(s) shall conform to acceptable engineering standards and practices. Each system shall be designed and operated so as to provide reasonably adequate and safe service to its customers and shall conform to the requirements of the Department and this General Order.
(1) A professional Civil, Mechanical, or Electrical engineer registered in the State of California shall approve all design and construction documents of a utility's water or wastewater system(s) as required by the California Business and Professions Code Sections 6700 - 6799, or its successor.
(2) The design and construction of distribution reservoirs must conform to the requirements of the DPH's Waterworks Standards, CCR Title 22, Section 64585 with reference to sanitation and potability of water.
(3) All new mains, pumps, tanks, wells and other facilities for handling potable water and repaired mains and other facilities shall be thoroughly disinfected before being connected to the system. The method of disinfection shall be conducted in accordance with Waterworks Standards, CCR Title 22, Sections 64580, 64582, and 64583, or their successors.
B. For systems applying for federal funds, under the Drinking Water State Revolving Fund or its successors, applicants must describe the design basis of all new facilities to be constructed using the criteria contained in the technical, managerial, and financial requirements of Waterworks Standards, CCR Title 22, Chapter 12, Sections 63026, 63027, and 63028, or their successors.
2. Materials and Specifications
(1) Materials used to construct component parts of a water system including, but not limited to, conduits, pipes, couplings, caulking materials, protective linings and coatings, services, valves, hydrants, pumps, tanks, backflow devices, and reservoirs, shall be capable of withstanding the internal and external forces to which they may be subjected in service per applicable AWWA Standards.
(a) No person shall use any pipe, plumbing fitting or fixture, solder, or flux that is not "lead free" in the installation or repair of any water system, except when necessary for the repair of leaded joints of cast iron pipes.
For the purposes of this section, "lead free" means in compliance with California Health and Safety Code Section 116875, as amended by Stats. 2006 Ch. 853 or a subsequent enactment.
(b) Materials and equipment shall be selected to mitigate corrosion, electrolysis and deterioration.
(2) Materials used to construct component parts of wastewater system(s) including, but not limited to, conduits, pipes, couplings, caulking materials, protective linings and coatings, valves, pumps, tanks, backflow devices, and reservoirs, shall be capable of withstanding the internal and external forces to which they may be subjected in service per applicable standards.
Materials and equipment shall be specified by a properly qualified person.
C. Newly Developed Materials and Equipment
The Commission does not intend to prevent the use of newly developed materials and equipment that otherwise meet the requirements described above.
3. Distribution System
(1) Water mains shall be installed below the frost line or be otherwise protected to prevent freezing and shall have no less than 30-inches of cover over the top of the pipe in public streets or alleys except when it is necessary to avoid underground obstructions or rocky or hardpan conditions where such depth is not feasible.
(2) All pipe and service lines that are not electrically continuous and installed using the open cut method shall be installed with continuous tracer tape or wire.
Water mains shall be laid out only in segmented grids and looped, and should be located within streets, where practical. Dead-end water mains shall be installed only if:
(1) Looping or gridding is impractical due to topography, geology, pressure zone boundaries, unavailability of easements or locations of users; or
(2) The main is to be extended in the near future and the planned extension will eliminate the dead-end conditions.
(1) The distribution system shall be of adequate size, and designed in conjunction with related facilities to maintain the minimum flow and pressure requirements of this General Order.
(2) In no event shall the minimum pipe size for new mains be less than six inches in diameter when used in conjunction with a fire protection system. Otherwise, the minimum pipe size for new mains shall be no less than four inches in diameter.
The minimum separation distances shall be as set forth in the DPH's Waterworks Standards, CCR Title 22, Section 64572, or its successor.
(1) Sufficient valves shall be provided on water mains in accordance with the DPH's Waterworks Standards, CCR Title 22, Sections 64577 and 64578, or their successors.
(2) A flushing valve or blowoff shall be provided at the end of each newly installed dead-end water main (per Waterworks Standards, CCR Title 22, Section 64575.)
4. Materials Standards for Water Mains
All new water main materials used in the distribution system shall comply with the Department's Waterworks Standards, CCR Title 22, Section 64570, or its successor. The utility shall consider the cost effectiveness, for the intended application, of the material it selects.
5. Service Connection Pipe and Fittings
(1) Service connection pipe and fittings shall be designed for cold water working pressures of not less than 150 psi.
(2) Copper tubing shall be commercial designation of type K or L. Plastic tubing and fittings shall be products tested and certified as suitable for use in potable water piping systems by the National Sanitary Foundation, the Canadian Standards Association Testing Laboratory, or another testing agency acceptable to the Department.
B. Conditions for Adding Service Connections
(1) New service connections shall not be added to a water distribution system if the additional connections will cause system pressures or water supply to be reduced below the standards set forth in this General Order.
(2) New service connections shall not be added to a wastewater distribution system if the additional connections will cause the system to exceed the capacity requirements set forth in this General Order.
The size, design, material and installation of the water service line shall conform to the reasonable requirements of the utility, provided, however, that the minimum size of the pipe shall not be less than ¾-inch nominal size. The utility may require the customer to provide such data as may be necessary for the utility to properly size a service larger than ¾-inch nominal size consistent with the requirements of fire flow.
D. Depth of Water Service Line
Except in unusual conditions all service pipes shall be laid at a depth sufficient to prevent freezing, except where services are not intended for use during freezing weather and are drained prior to such weather, and at a depth of not less than 18 inches except at its termination in connecting with the meter or customer's piping.
6. Distribution Reservoirs
Distribution reservoirs (as defined in Waterworks Standards, CCR Title 22, Section 64551.10) shall meet the criteria specified in the DPH's Waterworks Standards, CCR Title 22, Section 64585.
7. Recycled Water and Reservoirs
No utility may use a reservoir that is directly augmented with recycled water as a source of supply, unless approved by the Department.
8. Reliability for Water Facilities
A. Surface Water Treatment Facilities shall meet the reliability standards set forth in the DPH's Waterworks Standards, CCR Title 22, Section 64659, or its successor.
B. All other critical equipment not addressed above shall have adequate redundancy and reliability, including fixed or portable backup power, incorporated as determined by the utility and approved by the Commission to meet the requirements of this General Order.
9. Sewer Systems
(1) Sewer mains shall be sized for the ultimate development of the area, and shall be designed for an average daily per capita flow of sewage of not less than 100 gallons per day.
(2) The minimum size for mains and submains shall be eight inches in diameter.
(3) Submains shall be designed to carry, when running full, not less than 400 gallons daily per capita contributions of sewage.
(4) New sewer mains shall be installed at least 10 feet horizontally from, and at least one foot vertically below, any parallel pipeline conveying potable water.
(1) Utility service laterals shall be designed to carry, when running full, not less than 400 gallons daily per capita contributions of sewage.
(2) The minimum size for a service lateral shall be 4 inches.
(3) Utility service laterals shall maintain a 2% minimum and 4% maximum slope.
