Water Treatment, Alternate Sources, and Special Systems

Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:

• CPC § 1505.16 High relevance — show source text

  0 - 1505.16|†|†||†||||||||||||||||X||||| |Figure 1505.10||||||||||||||||||||X||||| |Table 1505.16||†||†||||||||||||||||X||||| |1506.0 - 1506.4 Exceptions||X||X||||||||||||||||||||| |1506.4 & Exceptions||||||||||||||||||||X||||| |1506.5||X||X||||||||||||||||||||| |1506.6 -1506.10.6||X||X||||||||||||||||||||| |1506.12||X||X|X|||||||||||||||||||| |1506.13||X||X|||||||||||||||||||||

  This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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  CHAPTER 15

  ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

  1501.0 General.

  1501.1 Applicability. [BSC-CG, DWR & HCD 1] The provisions of this chapter shall apply to the construction, alteration, discharge, use and repair of alternate water source systems for nonpotable applications.

  1501.1.1 Allowable Use of Alternate Water. Where approved or required by the Authority Having Jurisdiction, alternate water sources [reclaimed (recycled) water, gray water, and on-site treated nonpotable gray water] shall be permitted to be used instead of potable water for the applications identified in this chapter. 1501.2 System Design. [BSC-CG, HCD 1 & DWR] Alternate water source systems shall be designed in accordance with this chapter by a registered design professional or licensed person who demonstrates competency to design the alternate water source system as required by the Authority Having Jurisdiction . Components, piping, and fittings used in any alternate water source system shall be listed.

  [BSC-CG & HCD 1] Irrigation design plans shall meet the requirements of the California Code of Regulations, Title 23, Division 2, Chapter 2.7, Model Water Efficient Landscape Ordinance.

  Exceptions:

  (1) A registered design professional or a licensed person who demonstrates competency to design the alternate water source system is not required to design gray water systems having a maximum discharge capacity of 250 gallons per day (gal/d) (0.011 L/s) for single family and multi-family dwellings.

  (2) A registered design professional or a licensed person who demonstrates competency to design the alternate water source system is not required to design an on-site treated nonpotable water system for single-family dwellings having a maximum discharge capacity of 250 gal/d (0.011 L/s).

  **1501.3 Permit.

• CPC § 1501.5.1 High relevance — show source text

  Exception: [DWR] Recycled water supply systems that are within or a part of a building shall comply with Section 1505.16 .

  1501.5.1 Maintenance Responsibility. The required maintenance and inspection of alternate water source systems shall be the responsibility of the property owner unless otherwise required by the Authority Having Jurisdiction.

  1501.6 Operation and Maintenance Manual. [BSC- CG, HCD 1 & DWR] An operation and maintenance manual for gray water, on-site treated nonpotable water , [DWR] and recycled water supply systems required to have a permit in accordance with Section 1501.3, Section 1505.2, and Section 1506.2 shall be supplied to the building owner by the system designer or installer . The operation and maintenance manual shall include the following:

  (1) Diagram(s) of the entire system and the location of system components.

  (2) Instructions for operating and maintaining the system.

  (3) Instructions on maintaining the required water quality for on-site treated nonpotable water systems.

  (4) Details on startup, shutdown, and deactivating the system for maintenance, repair, or other purposes.

  (5) Applicable testing, inspection, and maintenance frequencies in accordance with Section 1501.5 [DWR] or Section 1505.16 as applicable .

  (6) A method of contacting the installer and/or manufacturer(s).

  (7) Directions to the owner or occupant that the manual shall remain with the building throughout the life cycle of the structure.

  1501.7 Minimum Water Quality Requirements. [BSC- CG, HCD 1 & DWR] The minimum water quality for alternate water source systems shall meet the applicable water quality requirements for the intended application as determined by the Authority Having Jurisdiction. In the absence of water quality requirements, for on-site treated nonpotable systems, the water quality requirements of IAPMO IGC 324 or NSF/ANSI 350 shall apply. [BSC-CG & HCD 1] Water quality requirements for on-site treated nonpotable graywa- ter shall comply with this section and Section 1506.10.2.

  Exception s :

  (1) Water treatment is not required for gray water used in a disposal field or for subsurface or subsoil irrigation.

  (2) [DWR] Recycled water shall comply with the water quality requirements of Section 1505.15.

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  ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

  TABLE 1501.5 [BSC-CG] RECOMMENDED MINIMUM ALTERNATE WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY

  DESCRIPTION	MINIMUM FREQUENCY
  Inspect and clean filters and screens, and replace (where necessary).	In accordance with manufacturer’s instructions, and/or the Authority Having Jurisdiction, or every 3 months.
  Inspect and verify that disinfection, filters,

• CPC § 1701.1 High relevance — show source text

  Chapter 16 Nonpotable Rainwater Catchment Systems.

  Chapter 16 regulates nonpotable rainwater catchment systems that include irrigation; toilet and urinal flushing with proper treatment; provisions where permits are required; maintenance of alternate water sources; and minimum water quality. This chapter provides guidance on how to optimize rainwater use while ensuring there is a decrease of risk to consumers from poor design, installation, and maintenance. Rainwater harvesting is the process of capturing, channeling, and storing water runoff for later use. Most systems are constructed of three principal components: the catchment area, the collection device, and the conveyance system.

  Chapter 17 Referenced Standards.

  Chapter 17 provides two comprehensive tables with referenced standards. The standards listed in Table 1701.1 are applied as indicated in the applicable reference section(s). A list of additional approved standards, publications, practices, and guides that are not referenced in specific sections appear in Table 1701.2.

  Referenced standards set forth specific details of accepted practices, materials specifications, or test methods in many specialized applications. Standards provide an efficient method of conveying complex information and specifications on the performance requirements for materials, products, systems, application, and installation. The manner and purpose for a standard’s use and, in turn, code compliance, must be definitive in all references to the standard. If the standard is intended to be a requirement for judging code compliance, the code must state its intent for use. The standard should adequately address a defined need and at the same time specify the minimum performance requirements, technical characteristics and methods of testing, and required test results.

  The referenced standards tables are organized in a manner that makes it easy to find specific standards in alphabetical order, and by acronym of the publishing agency of the standard. The tables list the title of the standard, the edition, and any addenda. Contact information for each publishing agency is provided at the end of the chapter.

  Appendix A Recommended Rules for Sizing the Water Supply System.

  Appendix A provides a method of sizing the water supply and distribution system that provides precise calculations to establish the proper pressures and flow to the system’s fixtures. The goal of sizing the system is to deliver an acceptable volume of water to the most hydraulically remote fixture during minimum pressure and maximum flow conditions; provide satisfactory water pressure to the most hydraulically remote fixture during minimum pressure and maximum flow conditions; and to prevent excessive water velocity during maximum flow conditions.

  Appendix B Explanatory Notes on Combination Waste and Vent Systems.

  Appendix B contains general guidelines for the design and installation of combination waste and vent systems. These systems are designed for waste piping and are purposely oversized to serve as both a waste and vent pipe to avoid excessive pneumatic effects at fixture drains.

  Appendix C Alternate Plumbing Systems.

  The intent of this appendix is to provide clarification of procedures for the design and approval of engineered plumbing systems, alternate materials, and equipment that are not specifically covered in other parts of the code. Alternative methods are allowed to be used where approved by the authority having jurisdiction. Approval of alternatives is based on a demonstration showing that the method or material used is at least equivalent in strength, deflection, and capacity to that provided by the prescriptive methods and materials.

  Appendix D Sizing Storm Water Drainage Systems.

  Appendix D provides general guidelines for the sizing of stormwater drainage systems. There are two pieces of information that must always be a given. They are the roof size and the rate of rainfall f

• CPC § 1505.15. High relevance — show source text

  Exception s :

  (1) Water treatment is not required for gray water used in a disposal field or for subsurface or subsoil irrigation.

  (2) [DWR] Recycled water shall comply with the water quality requirements of Section 1505.15.

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  ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

  TABLE 1501.5 [BSC-CG] RECOMMENDED MINIMUM ALTERNATE WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY

  DESCRIPTION	MINIMUM FREQUENCY
  Inspect and clean filters and screens, and replace (where necessary).	In accordance with manufacturer’s instructions, and/or the Authority Having Jurisdiction, or every 3 months.
  Inspect and verify that disinfection, filters, and water quality treatment devices and systems are operational and maintaining minimum water qual- ity requirements as determined by the Authority Having Jurisdiction.	In accordance with manufacturer’s instructions, and the Authority Having Jurisdiction.
  Inspect pumps and verify operation.	In accordance with manufacturer’s instructions, and/or the Authority Having Jurisdiction, or after installation and every 12 months thereafter.
  Inspect valves and verify operation.	In accordance with manufacturer’s instructions, and/or Authority Having Jurisdiction, or after installation and every 12 months thereafter.
  Inspect pressure tanks and verify operation.	In accordance with manufacturer’s instructions, and/or the Authority Having Jurisdiction, or after installation and every 12 months thereafter.
  Clear debris from and inspect storage tanks, lock- ing devices, and verify operation.	In accordance with manufacturer’s instructions, and/or the Authority Having Jurisdiction, or after installation and every 12 months thereafter.
  Inspect caution labels and marking.	In accordance with manufacturer’s instructions, and/or the Authority Having Jurisdiction, or after installation and every 12 months thereafter.
  Inspect and maintain mulch basins for gray water irrigation systems.	As needed to maintain mulch depth and prevent ponding and runoff.
  Cross-connection inspection and test*	In accordance with this chapter, and/or the Authority Having Jurisdiction, or after installation and every 12 months thereafter.

  • The cross-connection test shall be performed in the presence of the Authority Having Jurisdiction in accordance with the requirements of this chapter , unless site conditions do not require it. Alternate testing requirements shall be permitted by the Authority Having Jurisdiction ..

  1501.8 Material Compatibility. Alternate water source systems shall be constructed of materials that are compatible with the type of pipe and fitting materials, water treatment, and water conditions in the system.

  1501.9 Signage. [BSC-CG, HCD 1, HCD 2 & HCD 1- AC] Signage for on-site treated nonpotable gray water shall comply with Sections 1501.9.1 and 1501.9.2. [DWR] Signage for reclaimed (recycled) water shall comply with Section 1505.13.

• CPC § 1502.3.3 Medium relevance — show source text

  (3) The drain on the alternate water source system shall be checked for flow during the test and fixtures, potable and alternate water source, shall be tested and inspected for flow. Flow from an alternate water source system outlet indicates a cross-connection. No flow from a potable water outlet shall indicate that it is connected to the alternate water source sys tem.

  (4) The potable water system shall then be depressurized and drained.

  (5) The alternate water source system shall then be activated and pressurized. When an alternate water source is not available for the initial cross-connec- tion test, a temporary connection to a potable water supply shall be required. At the conclusion of the ini- tial cross-connection test, the temporary connection to the potable water supply shall be disconnected.

  (6) The alternate water source system shall remain pressurized for a minimum period specified by the Authority Having Jurisdiction while the potable water system is empty. The minimum period the potable water system is to remain depressurized shall be determined on a case-by-case basis, but in no case shall that period be less than 1 hour.

  (7) Fixtures, potable, and alternate water source shall be tested and inspected for flow. Flow from a potable water system outlet indicates a cross-connection. No flow from an alternate water source outlet will indicate that it is connected to the potable water system.

  (8) The drain on the potable water system shall be checked for flow during the test and at the end of the

  test.

  (9) Where there is no flow detected in the fixtures which would indicate a cross-connection, the potable water system shall be repressurized. 1502.3.3 Discovery of Cross-Connection. If a cross-connection is discovered, the following procedure, in the presence of the Authority Having Jurisdiction, shall be activated immediately:

  (1) Notify the Authority Having Jurisdiction of the cross connection.

  ( 2 ) The alternate water source piping to the building and its premises shall be shutdown at the meter, and the alternate water source riser shall be drained.

  ( 3 ) Potable water piping to the building and its prem- ises shall be shutdown at the meter.

  ( 4 ) The cross-connection shall be uncovered and disconnected.

  ( 5 ) The building and its premises shall be retested in accordance with Section 1502.3.1 and Section

  1502.3.2.

  ( 6 ) The potable water system shall be chlorinated with 50 parts-per-million (ppm) chlorine for 24 hours.

  ( 7 ) The potable water system shall be flushed after 24 hours, and a standard bacteriological test shall be performed. Where test results are acceptable, the potable water system shall be permitted to be recharged. 1502.4 Separation Requirements. Underground alternate water source service piping other than gray water shall be separated from the building sewer in accordance with this code. Pipes carrying treated nonpotable water shall be permitted to be run or laid in the same trench as potable water pipes with a 12 inch (305 mm) minimum vertical and horizontal separation where both pipe materials are approved for use within a building. Where horizontal piping materials do not comply with this requirement, the minimum separation shall be increased to 60 inches (1524 mm). The potable water piping shall be installed at an elevation above the treated nonpotable water piping.

• CPC § 1502.3.1 Medium relevance — show source text

  (1) Notify the Authority Having Jurisdiction of the cross connection.

  ( 2 ) The alternate water source piping to the building and its premises shall be shutdown at the meter, and the alternate water source riser shall be drained.

  ( 3 ) Potable water piping to the building and its prem- ises shall be shutdown at the meter.

  ( 4 ) The cross-connection shall be uncovered and disconnected.

  ( 5 ) The building and its premises shall be retested in accordance with Section 1502.3.1 and Section

  1502.3.2.

  ( 6 ) The potable water system shall be chlorinated with 50 parts-per-million (ppm) chlorine for 24 hours.

  ( 7 ) The potable water system shall be flushed after 24 hours, and a standard bacteriological test shall be performed. Where test results are acceptable, the potable water system shall be permitted to be recharged. 1502.4 Separation Requirements. Underground alternate water source service piping other than gray water shall be separated from the building sewer in accordance with this code. Pipes carrying treated nonpotable water shall be permitted to be run or laid in the same trench as potable water pipes with a 12 inch (305 mm) minimum vertical and horizontal separation where both pipe materials are approved for use within a building. Where horizontal piping materials do not comply with this requirement, the minimum separation shall be increased to 60 inches (1524 mm). The potable water piping shall be installed at an elevation above the treated nonpotable water piping.

  Exception: [DWR] Recycled water supply systems that are within or a part of a building shall comply with Section 1505.12.

  1502.5 Abandonment. Alternate water source systems that are no longer in use or fail to be maintained in accordance with Section 1501.5 shall be abandoned. Abandonment shall comply with Section 1502.5.1 and Section 1502.5.2.

  1502.5.1 General. An abandoned system or part thereof covered under the scope of this chapter shall be disconnected from remaining systems, drained, plugged, and capped in an approved manner.

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  ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

  1502.5.2 Underground Tank. An underground water storage tank that has been abandoned or otherwise discontinued from use in a system covered under the scope of this chapter shall be completely drained and filled with earth, sand, gravel, concrete, or other approved material or removed in a manner satisfactory to the Authority Having Jurisdiction. 1502.6 Sizing. Unless otherwise provided for in this chapter, alternate water source piping shall be sized in accordance with Chapter 6 for sizing potable water piping.

• CPC § 1505.14.2.1 Medium relevance — show source text

  (1) Notify the Authority Having Jurisdiction of the cross-connection.

  (2) The reclaimed (recycled) water piping to the building and its premises shall be shut down at the meter, and the reclaimed (recycled) water riser shall be drained.

  (3) Potable water piping to the building and its premises shall be shut down at the meter.

  (4) The cross-connection shall be uncovered and disconnected.

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  ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

  (5) The building and its premises shall be retested in accordance with Section 1505.14.2.1 and

  Section 1505.14.2.2.

  (6) The potable water system shall be chlorinated with 50 parts-per-million (ppm) chlorine for 24 hours.

  (7) The potable water system shall be flushed after 24 hours, and a standard bacteriological test shall be performed. Where test results are acceptable, the potable water system shall be permitted to be recharged. 1505.14.2.4 Periodic Inspection. Periodic visual inspections of recycled water supply systems shall be required by the recycled water supplier or designee following the procedures in Section 1505.14.2.1. Pursuant to California Code of Regu- lations, Title 22, Section 60316, annual visual inspections shall be required for recycled water sup- ply systems that are within or a part of a building. 1505.15 Minimum Water Quality Requirements for Reclaimed (Recycled) Water. The minimum water qual- ity for reclaimed (recycled) water shall meet the applicable water quality requirements of California Code of Regulations, Title 22, Division 4, Chapter 3 (commencing with Section 60301) for disinfected tertiary recycled water and the appli- cable reclaimed (recycled) water use. The reclaimed (recy- cled) water supplier shall supply water in accordance with permits issued by the State Water Resources Control Board or Regional Water Quality Control Board. 1505.16 Maintenance and Inspection. Recycled water supply systems and components shall be inspected and main- tained in accordance with the manufacturer’s recommendations and/or as required by the Authority Having Jurisdiction. The frequency of testing, inspection, and maintenance shall be in accordance with Table 1505.16. The required inspection and maintenance shall be the responsibility of the property owner, unless otherwise required by the Authority Having Jurisdiction.

  1506.0 On-Site Treated Nonpotable Gray Water Sys- tems.

  1506.1 General. The provisions of this section shall apply to the installation, construction, alteration, and repair of onsite treated nonpotable gray water systems intended to supply uses such as water closets, urinals, trap primers for floor

  drains and floor sinks, above and belowground irrigation, and other uses approved by the Authority Having Jurisdiction.

• CPC § 4.2.1 Medium relevance — show source text

  1101.4.2.1, 1104.4.2.2

  AIR GAPS

  Backflow prevention . . . . . . 603.2, Table 603.2, 603.3.1, Table 603.3.1, 603.4.4

  Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0

  Discharge from drinking

  water treatment units . . . . . . . . . . . . . . . . . . . . . 611.2

  AIR TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .710.11

  ALTERATIONS AND REPAIRS

  Fuel gas piping . . . . . . . . . . . .1203.1, 1213.1.2, 1213.4.2

  Health care facilities . . . . . . . . . . . . . . . . . . . . . . .1301.5

  Plumbing systems . . . . . . . . . . . . . . . . . .102.4, 301.2.5 ALTERNATE MATERIALS, DESIGN,

  AND METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . .301.3

  ALTERNATE WATER SOURCE

  Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203.0

  For nonpotable applications . . .Chapter 15, Chapter 16 For special water features . . . . . . . . . . . . . . . . .L 406.1

  Future connections . . . . . . . . . . . . . . . . . . . . .1504.9.1

  Identification of piping . . . . . . . . . . . . . . . . . . . . .601.3.3 Nonpotable rainwater catchment system . . . . . . . . . . .Table 1601.5, 1602.4

  Potable rainwater

  catchment system . . . . . . . . . . . . . . . . . . . . . .K 102.2 ANODELESS RISER, DEFINITION . . . . . . . . . . . . . . .203.0

  APPLIANCES

  Automatically operated . . . . . . . . . . . .509.3.4, 509.5.7.1 Categorized vent diameter/area, definition . . . . . . . . . . . . . . . . . .203.0 Connections to building fuel gas piping . . . . . . . . . . . . . . . . . . . . . . . . .1212.0

  Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203.0

  Direct-vent . . . . . . . . . . . . . . . .206.0, 509.2.6, 509.5.10.1,

  509.8.1, 509.12

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• CPC § 103.3 Medium relevance — show source text

  R 103.3 Water Heaters. Water heaters shall be installed in accordance with Chapter 5 and the manufacturer’s recommendations and instructions.

  R 103.4 Potable Water Sources. Where a public water supply system is available, it shall be used. Private or alternate water sources shall comply with the potable water standards of the state, and local health authority. R 103.5 Water Supply to Fixtures. Each plumbing fixture shall be provided with an adequate supply of potable water in accordance with Chapter 6.

  R 103.6 Protection of Potable Water. The potable water supply shall be protected from pollution and contamination in accordance with Section 602.0 and Section 603.0. Backflow prevention shall be in accordance with Table 603.2.

  R 103.7 Water-Treatment Equipment. Where installed, water-treatment equipment shall comply with the requirements of Section 611.0.

  R 103.8 Testing. Installations of water supply, drainage, and venting systems shall be tested and inspected in accordance with the requirements of this code.

  R 201.0 Tiny House Fixtures.

  R 201.1 Fixtures. Plumbing fixtures shall comply with the requirements of Chapter 4.

  R 201.2 Kitchen. Each tiny house shall be provided with a kitchen sink.

  R 201.3 Bathroom. Each tiny house shall be provided with not less than one water closet, one lavatory, and one bath, shower or combination bath/shower.

  R 201.4 Bathtubs and Whirlpool Bathtubs. Where installed, bathtubs and whirlpool bathtubs shall be in accordance with Section 409.0.

  R 201.5 Showers Compartments. Where installed, shower compartment enclosures shall be not less than 30 inches (762 mm) wide by 30 inches (762 mm) long.

  R 201.6 Water Closet. Water closets shall be in accordance

  with Section 411.0.

  R 201.7 Lavatories. Lavatories shall be in accordance with

  Section 407.0.

  R 202.0 Tiny House Water Supply System. R 202.1 Water Service Outlet. Each tiny house shall be provided with a water service outlet delivering potable water. The water service outlet riser shall be not less than ¾ of an inch (20 mm) nominal pipe size. R 202.2 Sizing Water Supply and Distribution Sys- tems. Water distribution systems shall be sized in accordance with Section 610.0. Water supply piping, joints, and connections shall be installed in accordance with Chapter 6. R 202.3 Pressure. Each tiny house water distribution system shall be so designed and maintained at not less than 15 pounds force per square inch (psi) (103 kPa) at each fixture inlet in accordance with Section 608.1. Water pressure exceeding 80 psi (552 kPa), shall be limited in accordance with Section 608.2.

  R 203.0 Tiny House Drain, Waste, and Vent (DWV) System. R 203.1 General. Sanitary drain, waste, and vent (DWV) systems shall be installed in accordance with Chapter 7 and Chapter 9. The DWV system shall connect to the public sanitary waste system. Private sewage disposal systems shall be permitted where approved by the Authority Having Jurisdiction. See Appendix H for private sewage disposal system general guidelines.

• CPC § 406.0 Medium relevance — show source text

  L 406.0 Fountains and Other Water Features.

  L 406.1 Use of Alternate Water Source for Special Water Features. Special water features such as ponds and water fountains shall be provided with reclaimed (recycled) water, rainwater, or on-site treated nonpotable water where the source and capacity are available on the premises and approved by the Authority Having Jurisdiction.

  L 407.0 Meters.

  L 407.1 Required. A water meter shall be required for each building site connected to a public water system, including municipally supplied reclaimed (recycled) water. In other than single-family houses, a dedicated meter shall be installed in accordance with Table L 407.1.

  L 407.2 Approval. Dedicated meters, other than water utility meters shall be approved by the Authority Having Jurisdiction for the intended use.

  L 407.3 Remote Data Transfer Requirements. Where more than 10 non-utility-owned water meters are located at a building site, the meters shall include remote data transfer capability to collect and analyze the data at a single location.

  L 407.4 Access. Meters and submeters shall be accessible.

  L 408.0 Condensate Recovery. L 408.1 General. Condensate is permitted to be used as onsite treated nonpotable water when collected, stored, and treated in accordance with Section 1506.0.

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  APPENDIX L

  TABLE L 407.1

  DEDICATED WATER METERING REQUIREMENTS

  APPLICATION	REQUIREMENTS
  Cooling Towers	The makeup water supply to cooling towers, evaporative condensers, and fluid coolers. Cooling towers sharing a common basin can be grouped together using one meter.
  Evaporative Coolers	The makeup water supply to an evaporative cooler having an air flow exceeding 30 000 cubic feet per minute (ft3/min).
  Fluid Coolers and Chillers – Open Systems	The makeup water supply on water-cooled fluid coolers and chillers not utilizing closed- loop recir- culation.
  Hydronic Cooling Systems – Closed Loop	Systems with 50 ton or greater of cooling capacity and where a make-up water supply is connected.
  Hydronic Heating Systems	The makeup water supply to one or more boilers collectively exceeding 1 000 000 British thermal units per hour (Btu/h).
  Industrial Processes	The water supply to an industrial water-using process where the average consumption exceeds 1000 gallons per day (gal/d). Like equipment sharing one common water supply can be grouped together using one meter. Exception: Processes using untreated water where the water is directly returned to the original source after use.
  Landscape Irrigation	Landscape irrigation water where either of the following conditions exist: (1) Total accumulated landscape area with in-ground irrigation system exceeds 2500 square feet (ft2), or (2) Total accumulated landscape area using an automatic irrigation controller exceeds 1500 square feet (ft2) Exception: Where the water purveyor provides a separate water supply meter that serves only the irrigation system, an additional dedicated meter is not required.

• CPC § 1505.16 Medium relevance — show source text

  **_ The minimum water qual- ity for reclaimed (recycled) water shall meet the applicable water quality requirements of California Code of Regulations, Title 22, Division 4, Chapter 3 (commencing with Section 60301) for disinfected tertiary recycled water and the appli- cable reclaimed (recycled) water use. The reclaimed (recy- cled) water supplier shall supply water in accordance with permits issued by the State Water Resources Control Board or Regional Water Quality Control Board. 1505.16 Maintenance and Inspection. Recycled water supply systems and components shall be inspected and main- tained in accordance with the manufacturer’s recommendations and/or as required by the Authority Having Jurisdiction. The frequency of testing, inspection, and maintenance shall be in accordance with Table 1505.16. The required inspection and maintenance shall be the responsibility of the property owner, unless otherwise required by the Authority Having Jurisdiction.

  1506.0 On-Site Treated Nonpotable Gray Water Sys- tems.

  1506.1 General. The provisions of this section shall apply to the installation, construction, alteration, and repair of onsite treated nonpotable gray water systems intended to supply uses such as water closets, urinals, trap primers for floor

  drains and floor sinks, above and belowground irrigation, and other uses approved by the Authority Having Jurisdiction.

  Other approved nonpotable water sources including swim- ming pool backwash operations, air conditioner condensate, rainwater, cooling tower blow-down water, foundation drainage, steam system condensate, fluid cooler discharge water, food steamer discharge water, combination oven dis- charge water, industrial process water, and fire pump test water may be permitted to be collected for re-use by gray water sys- tems, as approved for the intended application. 1506.2 Plumbing Plan Submission. No permit for an on-site treated nonpotable gray water system shall be issued until complete plumbing plans, with data satisfactory to the Authority Having Jurisdiction, have been submitted and approved. [BSC-CG & HCD 1] Prior to commencing the issuance of permits for indoor gray water systems pursuant to state requirements relating to graywater, a city, county, city and county or other local agency shall seek consultation with the local public health department to ensure that local pub- lic health concerns are addressed in local standards or ordi- nances, or in issuing permits. See California Water Code Section 14877.3.

  1506.3 System Changes. No changes or connections shall be made to either the on-site treated nonpotable gray water system or the potable water system within a site containing an on-site treated nonpotable gray water system without approval by the Authority Having Jurisdiction. 1506.4 Connections to Potable or Recycled Water Supply Systems. On-site treated nonpotable gray water systems shall have no direct connection to a potable water supply or recycled water supply system.

  Exceptions:

  (1) Potable or reclaimed (recycled) water is permitted to be used as makeup water for a non-pressurized storage tank provided the makeup water supply inlet is protected by an air gap in accordance with this code.

• CPC § 411.3 Medium relevance — show source text

  Exceptions: (1) Where average annual rainfall is less than 12 inches (305 mm) and in landscape areas where the plant materials have an annual ETc of not exceeding 15 inches (381 mm), an in-ground irrigation system shall be allowed. (2) Where neither potable or reclaimed (recycled) water is used in the irrigation system, an in-ground irrigation system shall be allowed in 100 percent of the landscaped area and vegetative roofs. L 411.3 Vegetative Roofs and Walls. Irrigation systems using potable water for vegetative roofs and walls are prohibited.

  L 411.4 Maximum Velocity. Velocity of water flow shall not exceed 5 feet per second (1.5 m/s) for thermoplastic irrigation pipes. Velocity of water flow shall not exceed 7.5 feet per second (2.3 m/s) for metal irrigation pipes.

  L 411.5 Backflow Protection. Potable water and reclaimed water supplies to landscape irrigation systems shall be protected from backflow in accordance with this code and the Authority Having Jurisdiction.

  L 411.6 Use of Alternate Water Sources for Land- scape Irrigation. Where available by pre-existing treatment, storage, or distribution network, and where approved by the Authority Having Jurisdiction, alternative water source(s) shall be utilized for landscape irrigation. Where adequate capacity and volumes of pre-existing alternative water sources are available, the irrigation system shall be designed to use a minimum of 75 percent of alternative water for the annual irrigation demand before supplemental potable water is used. Exception: Plants grown for food production for direct human consumption. L 411.6.1 Master Valve. Where continuously pressurized alternate water sources supply an existing irrigation system, a master valve shall be installed at the point where the alternate water sources supply piping connects to the existing irrigation system downstream of the backflow preventer where required.

  L 411.6.2 Identification. Where alternate water sources supply an existing irrigation system, the existing sprinkler heads, valve boxes, the continuously pressurized line supplying the irrigation master valve, or any other components required by the Authority Having Jurisdiction, shall be colored purple. The piping supplying the irrigation master valve shall be identified in accordance with Chapter 15 of this code. L 411.6.2.1 Additional Zones. Newly installed zones shall have purple pipe.

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  2025 CALIFORNIA PLUMBING CODE 505

  ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

  APPENDIX L

  L 411.10 Mulched Planting Areas. Only low flow emitters with flow rates not to exceed 6.3 gallons (24 L) per hour are allowed to be installed in mulched planting areas with vegetation taller than 12 inches (305 mm). L 411.11 System Performance Requirements. The landscape irrigation system shall be designed and installed to:

  (1) Prevent irrigation water from runoff out of the irrigation

  zone.

  (2) Prevent water in the supply line drainage from draining out between irrigation events.

  (3) Not allow irrigation water to be applied onto or enter nontargeted areas including adjacent property and vegetation areas, adjacent hydrozones not requiring the irrigation water to meet its irrigation demand, non-vegetative areas, impermeable surfaces, roadways, and structures.