Rainwater System Design & Components

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

• CPC § 1604.1 High relevance — show source text

  20
  1604.1 - 1604.3
  1605.3
  1605.3.2
  1605.3.3|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.

  2025 CALIFORNIA PLUMBING CODE 325

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  CHAPTER 16

  NONPOTABLE RAINWATER CATCHMENT SYSTEMS

  1601.0 General.

  1601.1 Applicability. The provisions of this chapter shall apply to the installation, construction, alteration, and repair of nonpotable rainwater catchment systems.

  1601.1.1 Allowable Use of Alternate Water. Where approved or required by the Authority Having Jurisdiction, rainwater shall be permitted to be used instead of potable water for the applications identified in this chap ter.

  1601.2 System Design. Rainwater catchment systems shall be designed in accordance with this chapter by a person registered or licensed to perform plumbing design work or who demonstrates competency to design the rainwater catchment system as required by the Authority Having Jurisdiction . Components, piping, and fittings used in a rainwater catchment system shall be listed.

  [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 person registered or licensed to perform plumbing design work is not required to design rainwater catchment systems used for irrigation with a maximum storage capacity of 360 gallons (1363 L).

  (2) A person registered or licensed to perform plumbing design work is not required to design rainwater catchment systems for single family dwellings where outlets, piping, and system components are located on the exterior of the building.

  1601.3 Permit. It shall be unlawful for a person to construct, install, alter, or cause to be constructed, installed, or altered a nonpotable rainwater catchment system in a building or on a premise without first obtaining a permit to do such work from the Authority Having Jurisdiction.

  Exceptions:

  (1) A permit is not required for exterior rainwater catchment systems used for outdoor non-spray irrigation with a maximum storage capacity of 5000 gallons (18 927 L) where the tank is supported directly upon grade and the ratio of height to diameter or width does not exceed 2 to 1 and it does not require electrical power or a makeup water supply connection. (2) [HCD 1 & HCD 2] A permit is not required for exterior rainwater catchment systems used for spray irrigation with a maximum storage capacity of 360 gallons (1363 L). 1601.4 Component Identification. System components shall be properly identified as to the manufacturer.

• CPC § 1601.3 High relevance — show source text

  2
  1601.3 & Exceptions 1 & 2
  1601.5
  1601.6
  1601.7
  1602.4_& Exceptions_
  1602.7
  1603.3
  1603.3.1 &Exception
  1603.4
  1603.4.1
  Table 1603.4
  1603.7
  1603.8
  1603.9
  1603.10_A & B_
  1603.12
  1603.20
  1604.1 - 1604.3
  1605.3
  1605.3.2
  1605.3.3|X|||X||||||||||||||||||||| |Adopting Agency
  Adopt Entire Chapter
  Adopt Entire Chapter as
  amended (amended
  sections listed below)
  Adopt only those sections
  that are listed below
  Chapter/Section
  1601.2
  1601.3 & Exceptions 1 & 2
  1601.5
  1601.6
  1601.7
  1602.4_& Exceptions_
  1602.7
  1603.3
  1603.3.1 &Exception
  1603.4
  1603.4.1
  Table 1603.4
  1603.7
  1603.8
  1603.9
  1603.10_A & B_
  1603.12
  1603.20
  1604.1 - 1604.3
  1605.3
  1605.3.2
  1605.3.3|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.

  2025 CALIFORNIA PLUMBING CODE 325

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  CHAPTER 16

  NONPOTABLE RAINWATER CATCHMENT SYSTEMS

  1601.0 General.

  1601.1 Applicability. The provisions of this chapter shall apply to the installation, construction, alteration, and repair of nonpotable rainwater catchment systems.

  1601.1.1 Allowable Use of Alternate Water. Where approved or required by the Authority Having Jurisdiction, rainwater shall be permitted to be used instead of potable water for the applications identified in this chap ter.

  1601.2 System Design. Rainwater catchment systems shall be designed in accordance with this chapter by a person registered or licensed to perform plumbing design work or who demonstrates competency to design the rainwater catchment system as required by the Authority Having Jurisdiction . Components, piping, and fittings used in a rainwater catchment system shall be listed.

• CPC § 1.11.0. High relevance — show source text

  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.

  2025 CALIFORNIA PLUMBING CODE 491

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  APPENDIX K

  POTABLE RAINWATER CATCHMENT SYSTEMS

  The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

  K 101.0 General.

  K 101.1 Applicability. The provisions of this appendix shall apply to the installation, construction, alteration, and repair of potable rainwater catchment systems. K 101.2 System Design. Potable rainwater catchment systems in accordance with this appendix shall be designed by a registered design professional or person deemed competent by the Authority Having Jurisdiction to perform potable rainwater catchment system design work. Where required, rainwater catchment systems shall be seismically restrained against earthquakes in accordance with the building code. K 101.3 Permit. It shall be unlawful for a person to construct, install, or alter, or cause to be constructed, installed, or altered a potable rainwater catchment systems in a building or on a premise without first obtaining a permit to do such work from the Authority Having Jurisdiction. K 101.3.1 Plumbing Plan Submission. No permit for a rainwater catchment system requiring a permit shall be issued until complete plumbing plans, with data satisfactory to the Authority Having Jurisdiction, have been submitted and approved. No changes or connections shall be made to either the rainfall catchment or the potable water system within a site containing a rainwater catchment water system without approval by the Authority Having Jurisdiction. K 101.3.2 System Changes. No changes or connections shall be made to either the rainwater catchment system or the potable water system within a site containing a rainwater catchment system requiring a permit without approval by the Authority Having Jurisdiction. K 101.4 Product and Material Approval. System components shall be properly identified as to the manufacturer. K 101.4.1 Plumbing Materials and Systems. Pipe, pipe fittings, traps, fixtures, material, and devices used in a potable rainwater system shall be listed or labeled (thirdparty certified) by a listing agency (accredited conformity assessment body) and shall be in accordance with approved applicable recognized standards referenced within this code, and shall be free from defects. Unless otherwise provided for in this appendix, materials, fixtures, or devices used or entering into the construction of plumbing systems, or parts thereof shall be submitted to the Authority Having Jurisdiction for approval.

  K 101.5 Maintenance and Inspection. Potable rainwater catchment systems and components shall be inspected and maintained in accordance with Section K 101.5.1 through Section K 101.5.3.

  K 101.5.1 Frequency. Potable rainwater catchment systems and components shall be inspected and maintained in accordance with Table K 101.5.1 unless more

  frequent inspection and maintenance are required by the manufacturer.

• CPC § 220.0 Medium relevance — show source text

  220.0 – R –

  Rainwater. [BSC-CG & HCD 1] Precipitation on any pub- lic or private parcel that has not entered an offsite storm drain system or channel, a flood control channel, or any other stream channel, and has not previously been put to beneficial use. Rainwater Catchment System. [BSC-CG & HCD 1] A facility designed to capture, retain, and store rainwater flow- ing off a building, parking lot, or any other manmade imper- vious surface for subsequent onsite use. Rainwater catchment system is also known as “Rainwater Harvesting System” or “Rainwater Capture System.” Rainwater Storage Tank. The central component of the rainwater catchment system. Also, known as a cistern or rain barrel.

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  DEFINITIONS

  Receiving Landscape. [BSC-CG & HCD 1] Includes features such as soil, basins, swales, mulch, and plants.

  Receptor. An approved plumbing fixture or device of such material, shape, and capacity as to adequately receive the discharge from indirect waste pipes, so constructed and located as to be readily cleaned.

  Reclaimed (Recycled) Water. [BSC-CG, HCD 1 & DWR] Nonpotable water that meets California State Water Resources Control Board statewide uniform criteria for dis- infected tertiary recycled water. Reclaimed (recycled) water is also known as “recycled water” or “reclaimed water”.

  Recycled Water Supply System. [DWR] The building supply pipe, the water distribution pipes, and the necessary connecting pipes, fittings, control valves, backflow preven- tion devices, and all appurtenances carrying or supplying reclaimed (recycled) water in or adjacent to the building or within the premises.

  Registered Design Professional. An individual who is registered or licensed by the laws of the state to perform such design work in the jurisdiction.

  Regulating Equipment. Includes valves and controls used in a plumbing system that is required to be accessible or readily accessible.

  Relief Vent. A vent, the primary function of which is to provide circulation of air between drainage and vent systems or to act as an auxiliary vent on a specially designed system.

  Remote Outlet. Where used for sizing water piping, it is the furthest outlet dimension, measuring from the meter, either the developed length of the cold-water piping or through the water heater to the furthest outlet on the hot-water piping.

  Rim. See Flood-Level Rim.

  Riser. A water supply pipe that extends vertically one full story or more to convey water to branches or fixtures.

  Roof Drain. A drain installed to receive water collecting on the surface of a roof and to discharge it into a leader, downspout, or conductor.

  Roof Washer. A device or method for removal of sediment

  and debris from a collection surface by diverting initial rainfall from entry into the cistern(s). Also, known as a first flush device.

• CPC § 0.293 Medium relevance — show source text

  For SI units: 1000 British thermal units per hour = 0.293 kW, 1 cubic foot = 0.0283 m [3]

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  CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

  APPENDIX K - POTABLE RAINWATER CATCHMENT SYSTEMS

  (Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
  Adopting Agency	BSC	BSC- CG	SFM	1	2	1-AC	AC	** SS**	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
  Adopt Entire Chapter
  Adopt Entire Chapter as amended (amended sections listed below)
  Adopt only those sections that are listed below
  Chapter/Section

  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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  APPENDIX K

  POTABLE RAINWATER CATCHMENT SYSTEMS

  The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

  K 101.0 General.

  K 101.1 Applicability. The provisions of this appendix shall apply to the installation, construction, alteration, and repair of potable rainwater catchment systems. K 101.2 System Design. Potable rainwater catchment systems in accordance with this appendix shall be designed by a registered design professional or person deemed competent by the Authority Having Jurisdiction to perform potable rainwater catchment system design work. Where required, rainwater catchment systems shall be seismically restrained against earthquakes in accordance with the building code.

• CPC § 1701.1 Medium 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 § 1602.6 Medium relevance — show source text

  The test shall be ruled successful by the Authority Having Jurisdiction before final approval is granted. 1602.6 Sizing. The design and size of rainwater drains, gutters, conductors, and leaders shall comply with Chapter 11 of this code.

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  NONPOTABLE RAINWATER CATCHMENT SYSTEMS

  1602.7 Rainwater Catchment System Materials. Rain- 1603.3 Rainwater Catchment Collection Surfaces. water catchment system materials shall comply with Section Rainwater shall be collected from roof surfaces or other 1602.7.1 through Section 1602.7.3 . impervious manmade, aboveground collection surfaces. 1602.7.1 Water Supply and Distribution Materi- 1603.3.1 Other Surfaces. Natural precipitation colals. Rainwater catchment water supply and distribution lected from surface water runoff, vehicular parking surmaterials shall comply with the requirements of this code faces, or manmade surfaces at or below grade shall be in for potable water supply and distribution systems unless accordance with the water quality requirements for onotherwise provided for in this section. site treated nonpotable gray water systems in Section

  1506.0.

  1602.7.2 Rainwater Catchment System Drainage Materials. Materials used in rainwater catchment Exception: Collected rainwater or storm water used

  exclusively for subsurface landscape irrigation.

  drainage systems, including gutters, downspouts, conductors, and leaders shall be in accordance with the 1603.3.2 Prohibited Discharges. Overflows and requirements of this code for storm drainage. bleed-off pipes from roof-mounted equipment and appli ances shall not discharge onto roof surfaces that are

  1602.7.3 Storage Tanks. Rainwater storage tanks shall

  intended to collect rainwater without prior approval from

  comply with Section 1603.5.

  the Authority Having Jurisdiction.

  1602.8 Rainwater Catchment System Color and

  1603.4 Minimum Water Quality. The minimum water

  Marking Information. Rainwater catchment systems shall

  quality for harvested rainwater shall meet the applicable water

  have a colored background in accordance with Section 601.3.

  quality requirements for the intended applications as deter Rainwater catchment systems shall be marked, in lettering in

  mined by the Authority Having Jurisdiction. In the absence of

  accordance with Section 601.3.3, with the words: “CAU water quality requirements determined by the Authority Hav TION: NONPOTABLE RAINWATER, DO NOT DRINK.”

  ing Jurisdiction, the minimum treatment and water quality

• CPC § 3.3.106.1 Medium relevance — show source text

  Private Sewage Disposal System. A septic tank with the effluent discharging into a subsurface disposal field, into one or more seepage pits, or into a combination of subsurface disposal field and seepage pit or of such other facilities as may be permitted under the procedures set forth elsewhere in this code.

  Private Sewer. A building sewer that receives the discharge from more than one building drain and conveys it to a public sewer, private sewage disposal system, or another point of disposal. Proportioning System for Medical Air USP. A central supply that produces medical air (USP) reconstituted from oxygen USP and nitrogen NF by means of a mixer or blender.

  [NFPA 99:3.3.106.1]

  Public or Public Use. Applies to plumbing fixtures that are not defined as private or private use. Public Sewer. A common sewer directly controlled by public authority. Public Water System. A system for the provision to the public of water for human consumption through pipes or other constructed conveyances, if such system has at least fifteen service connections or regularly serves an average of twenty-five individuals daily for at least 60 days per year. Push Fit Fitting. A mechanical fitting where the connection is assembled by pushing the tube or pipe into the fitting and is sealed with an o-ring. PVC. Polyvinyl Chloride.

  PVDF. Polyvinylidene Fluoride.

  219.0 – Q –

  Quick-Disconnect Device. A hand-operated device that provides a means for connecting and disconnecting a hose to a water supply, and that is equipped with a means to shut off the water supply when the device is disconnected. Quick-Disconnect Device, Fuel Gas. A hand-operated device that provides a means for connecting and disconnecting an appliance or an appliance connector to a gas supply and that is equipped with an automatic means to shut off the gas supply when the device is disconnected. [NFPA 54:3.3.27.3]

  220.0 – R –

  Rainwater. [BSC-CG & HCD 1] Precipitation on any pub- lic or private parcel that has not entered an offsite storm drain system or channel, a flood control channel, or any other stream channel, and has not previously been put to beneficial use. Rainwater Catchment System. [BSC-CG & HCD 1] A facility designed to capture, retain, and store rainwater flow- ing off a building, parking lot, or any other manmade imper- vious surface for subsequent onsite use. Rainwater catchment system is also known as “Rainwater Harvesting System” or “Rainwater Capture System.” Rainwater Storage Tank. The central component of the rainwater catchment system. Also, known as a cistern or rain barrel.

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  DEFINITIONS

  Receiving Landscape. [BSC-CG & HCD 1] Includes features such as soil, basins, swales, mulch, and plants.

• CPC § 2025 Medium relevance — show source text

  Appendix I Installation Standards.

  Installation standards are industry standards that specify procedures for the installation of plumbing and mechanical products, and the inspection methods and procedures employed for the examination of such systems. These comprehensive standards add detailed information and guidance that a manufacturer or product installation instructions may not fully address. These standards give the user confidence with options from industry experts for installing plumbing products and assemblies in a safe and professional manner.

  Appendix J Combination of Indoor and Outdoor Combustion and Ventilation Opening Design.

  Appendix J provides an example of how to determine the required combination of indoor and outdoor combustion air opening sizes for appliances. The combustion air example also provides a table that contains the required volume of a space per the appliance Btu/h input that is based on the standard method.

  Appendix K Potable Rainwater Catchment Systems.

  Potable rainwater catchment system is defined as a system that uses the principal of collecting and using rain from a rooftop or other man-made, aboveground collection surface. This appendix applies to new rainwater catchment installations, as well as changes, additions, maintenance, and repairs to existing installations. Rainwater harvesting is the practice of collecting the water produced during rainfall events before it has a chance to run off into a river or stream or soak into the ground and become groundwater.

  Appendix L Sustainable Practices.

  This appendix provides a comprehensive set of technically sound provisions that encourage sustainable practices and works toward improving the design and construction of plumbing systems that result in a positive long-term environmental impact. Environmental sustainability is important because it involves natural resources that human beings need for economic or manufactured capital. Their sustainability is defined by their reliance on infinitely available resources that are naturally occurring, constant, and free to access.

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  FORMAT OF THE UNIFORM PLUMBING CODE

  Appendix M Peak Water Demand Calculator.

  This appendix provides a method for estimating the demand load for the building water supply and principal branches for single- and multi-family dwellings with water-conserving plumbing fixtures, fixture fittings, and appliances.

  Appendix N Impact Of Water Temperature On The Potential For Scalding And Legionella Growth.

  Legionnaires’ disease is a serious issue that is a threat to many citizens. It is known that the higher the temperature, the lower the risk for Legionella growth, but the higher the temperature, the higher the possibility for scalding. This appendix addresses Legionella growth potential and scald potential within specified temperature ranges. It contains definitions for terms used to describe water temperatures such as cold, tepid, warm, tempered hot, and disinfecting hot. Since plumbing systems operate within various temperature ranges, the public has a document that identifies such temperature ranges and the “potential” dangers within these temperature ranges.

  Appendix O Non-Sewered Sanitation Systems.

  This appendix contains provisions on non-sewered sanitation systems which are suitable for use in temporary or permanent settlements, including refugee camps, and are equally suited to both public and private use in isolated locations. Additionally, the appendix provides general safety and performance requirements for design and testing of non-sewered sanitation systems for prefabricated integrated treatment units. These systems will apply to any integrated sanitation system that is not attached to a sewer.

  Appendix P Professional Qualifications.

  Appendix P provides a b

• CPC § 106.2.1 Medium relevance — show source text

  K 106.2.1 Size. The roof washer shall be sized to direct rainwater containing debris that has accumulated on the collection surface away from the storage tank. ARCSA/ASPE/ANSI 63 contains additional guidance on acceptable methods of sizing roof washers.

  K 106.2.2 Debris Screen. The inlet to the roof washer shall be provided with a debris screen or other approved means that protects the roof washer from the intrusion of debris and vermin. Where the debris screen is installed, the debris screen shall be corrosion resistant and shall have openings not larger than [1] ⁄ 2 of an inch (12.7 mm). K 106.2.3 Drain Discharge. Water drained from the roof washer, or pre-filter shall be diverted away from the storage tank and discharged to a disposal area that does not cause property damage or erosion. Roof washer drainage shall not drain over a public way. K 106.2.4 Automatic Drain. Roof washing systems shall be provided with an automatic means of self-draining between rain events.

  K 106.3 Roof Gutters. Gutters shall maintain a minimum slope and be sized in accordance with this code. K 106.4 Drains, Conductors, and Leaders. The design and size of rainwater drains, conductors, and leaders shall comply with this code. K 106.5 Size of Potable Water Piping. Potable rainwater system distribution piping shall be sized in accordance with this code for sizing potable water piping.

  K 107.0 Cleaning. K 107.1 General. The interior surfaces of tanks and equipment shall be clean before they are put into service.

  K 108.0 Supply System Inspection and Test. K 108.1 General. Rainwater catchment systems shall be inspected and tested in accordance with the applicable provisions of this code for testing of potable water and storm drainage systems. Storage tanks shall be filled with water to the overflow opening for 24 hours, and during the inspection, or by other means as approved by the Authority Having Jurisdiction. Seams and joints shall be exposed during the inspection and checked for water tightness.

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  CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

  APPENDIX L - SUSTAINABLE PRACTICES

  (Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

• CPC § 103.0 Medium relevance — show source text

  K 103.0 Potable Rainfall Catchment System Materials.

  K 103.1 Collections Surfaces. The collection surface for potable applications shall be constructed of a hard, impervious material and shall be approved for potable water use. Roof coatings, paints, and liners shall comply with NSF Protocol P151. K 103.1.1 Prohibited. Roof paints and coatings with lead, chromium, or zinc shall not be permitted. Wood roofing material and lead flashing shall not be permitted. K 103.2 Rainwater Catchment System Drainage Materials. Materials used in rainwater catchment drainage systems, including gutters, downspouts, conductors, and leaders shall be in accordance with the requirements of this code for storm drainage.

  K 103.3 Storage Tanks. Rainwater storage shall comply with Section K 105.0.

  K 103.4 Water Supply and Distribution Materials. Potable rainwater supply and distribution materials shall comply with the requirements of this code for potable water supply and distribution systems.

  K 104.0 Design and Installation.

  K 104.1 Collection Surfaces. Rainwater shall be collected from a roof or other cleanable aboveground surfaces specifically designed for rainwater catchment. A rainwater catchment system shall not collect rainwater from:

  (1) Vehicular parking surfaces

  (2) Surface water runoff

  (3) Bodies of standing water

  K 104.2 Prohibited Discharges. Overflows, condensate, and bleed-off pipes from roof-mounted equipment and appliances shall not discharge onto roof surfaces that are intended to collect rainwater.

  K 104.3 Minimum Water Quality. Upon initial system startup, the quality of the water for the intended application shall be verified at the point(s) of use as determined by the Authority Having Jurisdiction in accordance with Section K 104.3.1 and Section K 104.3.2. Water quality maintenance shall be in accordance with Section K 104.3.3.

  K 104.3.1 Private Potable Water System. In the absence of water quality requirements determined by the Authority Having Jurisdiction, the minimum water quality for a private potable water system at the point of use shall comply with Table K 104.3.1.

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  APPENDIX K

  TABLE K 104.3.1

  MINIMUM WATER QUALITY

  Escherichia coli (fecal coliform)	Non-detectable
  Protozoan Cysts	Non-detectable
  Viruses	Non-detectable
  Turbidity	<0.3 NTU

  K 104.3.2 Public Use Occupancies. The minimum water quality for a potable water system for public use occupancies at the point of use and testing procedures shall comply with the Environmental Protection Agency (EPA) Safe Drinking Water Act for a public water sys tem.

• CPC § 13000-2015 Medium relevance — show source text

  Qualifications Standard for Legionella Water Safety and Management
  Specialist|Professional
  Qualifications| |ASSE/IAPMO/ANSI Series
  13000-2015 (R2020)|Service Plumber and Residential Mechanical Service Technician Professional Quali-
  fications Standard|Professional
  Qualifications| |ASSE/IAPMO/ANSI
  13010-2015 (R2020)|Professional Qualifications Standard for the Service Plumber|Professional
  Qualifications| |ASSE/IAPMO/ANSI Series
  16000-2019|Professional Qualifications Standard for Inspectors and Plans Examiners|Professional
  Qualifications| |ASSE/IAPMO/ANSI
  16010-2019|Plumbing Inspector|Professional
  Qualifications| |ASSE/IAPMO/ANSI
  16040-2019|Plumbing Plan Examiner|Professional
  Qualifications| |ASSE/ARCSA/IAPMO/
  ANSI Series 21000-2017|Rainwater Catchment Systems Personnel|Professional
  Qualifications| |ASSE/IAPMO/ANSI
  21110-2017|Rainwater Catchment Systems Installers|Professional
  Qualifications| |ASSE/IAPMO/ANSI
  21120-2017|Rainwater Catchment Systems Designers|Professional
  Qualifications| |ASSE/IAPMO/ANSI
  21130-2017|Inspectors of Rainwater and Stormwater Catchment Systems|Professional
  Qualifications| |ANSI/CAN/IAPMO/ISO
  30500-2019|Non-Sewered Sanitation Systems - Prefabricated Integrated Treatment Units - Gen-
  eral Safety and Performance Requirements for Design and Testing|Miscellaneous| |IAPMO IGC 67-2014e1|Specialized ABS and PVC DWV Fittings|DWV Components| |IAPMO IGC 193-2020|Safety Plates, Plate Straps, Notched Plates and Safety Collars|Miscellaneous| |IAPMO IGC 226-2019|Drinking Water Fountains with or Without Chiller or Heater|Fixtures| |IAPMO IGC 244-2021|Tub and Shower Flow-Reduction Systems|Valves| |IAPMO IGC 262-2020|Corrugated Thermoplastic Tanks|DWV Components| |IAPMO IGC 267-2015e1|Hydrants Without Integral Backflow Preventers|Valves| |IAPMO IGC 276-2019|Bundled Expanded Polystyrene (EPS) Synthetic Aggregate Units|DWV Components| |IAPMO IGC 315-2016|Water Manifold Systems|Fittings| |IAPMO IGC 327-2016|Flexible Metallic Expansion Joints for Pressure Systems|Joints| |IAPMO IGC 330-2018|Recirculating Shower Systems|Fixtures| |IAPMO IGC 332-2017a|Hydronic Radiators|Miscellaneous| |IAPMO IGC 352-2020e1|Diverter Valves for use in Alternate Nonpotable Water Source System|Valves| |IAPMO IS 26-2019e2|Trenchless Insertion of Polyethylene (PE) Pipe for Sewer Laterals|Piping| |IAPMO PS 1-2019|Tank Risers|DWV Components| |IAPMO PS 23-2021|Dishwasher Drain Airgaps|Backflow Protection| |IAPMO PS 25-2019|Metallic Fittings Joining Polyethylene Pipe for Water Service and Yard