CALGreen · California Green Building Standards Code (CALGreen)
How does CALGreen define 'potable water' and related nonpotable terms?
CALGreen keeps its glossary of terms in Chapter 2 (**§ 202**) and refers to the California Plumbing Code for the operational definitions and technical rules for **potable** and **nonpotable** (graywater, reclaimed, rainwater, on‑site treated) systems — including required separation distances, filtration (**100 µm**), minimum pressure (**15 psi**), color coding (green/yellow/purple), signage, and cross‑connection testing — all of which are enforced by following the CPC provisions cited by CALGreen. filefile
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
CALGreen places its official definitions in Chapter 2, § 202 (Definitions) — see the CALGreen table of contents and definitions references in the code . CALGreen (Chapter 5 and the voluntary Appendices) refers to those Chapter 2 definitions for terms such as potable water, graywater, recycled (reclaimed) water, and alternate water source . The published CALGreen text retrieved here points the reader to Chapter 2 for the definitions but the verbatim wording of § 202 (Chapter 2 definitions) was not present in the retrieved CALGreen excerpts; therefore operational definitions and technical requirements that govern nonpotable systems in CALGreen rely on the California Plumbing Code (referenced throughout CALGreen) for detailed definitions and installation/control rules (e.g., alternate water source and graywater definitions and requirements) .
The code locates definitions in § 202 (Chapter 2); for installation and operational rules CALGreen defers to the California Plumbing Code definitions and provisions for alternate/nonpotable water systems.
Requirements in detail
Summary of how CALGreen structures the topic and where to find the operational rules:
- CALGreen identifies that Chapter 2 contains the defined terms — § 202 (Definitions) — and other divisions (e.g., Division 5.3) point back to those Chapter 2 terms .
- For technical definitions and mandatory technical controls (color coding, separation, filtration, pressure, cross‑connection testing, signage, permitted uses), CALGreen relies on the California Plumbing Code (CPC) chapters on Alternate Water Sources, Graywater, Reclaimed (recycled) water, and Rainwater Catchment; those CPC sections are referenced directly from CALGreen (see CALGreen Appendix/Divisions that require CPC compliance) .
Key defined terms (how CALGreen points to them)
- Potable water — listed as a defined term to be found in Chapter 2 (§ 202) of CALGreen; operational plumbing requirements for potable systems are in the California Plumbing Code (see CPC definitions and Chapters referenced by CALGreen) .
- Alternate Water Source — CALGreen/Plumbing Code treat this as a nonpotable source that includes gray water, on‑site treated nonpotable gray water, rainwater, and reclaimed (recycled) water; the CPC definition for Alternate Water Source enumerates these examples and is the operative technical definition used by the code (CPC Chapter 2 / definitions) .
- Graywater and On‑site treated nonpotable gray water — CALGreen references graywater as a defined term in Chapter 2 and uses CPC chapters for what graywater systems may supply and how they must be designed and tested (no direct connection to potable supply, diverter valves, prohibited spray irrigation, etc.) file.
- Reclaimed (recycled) water and Rainwater — treated separately in CPC chapters that CALGreen requires be followed for nonpotable uses; CALGreen voluntary measures encourage use but require CPC compliance for system design/marking/permits .
Decision‑relevant dimensions and values (quick reference table)
| Decision / threshold | Required value or marking | Code Reference |
|---|---|---|
| Where definitions live | Chapter 2, § 202 (Definitions) — CALGreen directs users to Chapter 2 for defined terms | § 202 |
| What counts as an Alternate Water Source | Includes graywater, on‑site treated nonpotable gray water, rainwater, reclaimed (recycled) water | CPC definition (Chapter 2) — § 202 (CPC definitions reference) |
| Minimum underground separation (potable vs treated nonpotable) | 12 inches (305 mm) vertical/horizontal where materials approved; otherwise 60 inches (1524 mm) | § 1502.4 (CPC) |
| Required filter for on‑site treated nonpotable graywater to toilets/urinals | 100 microns (100 µm) maximum particle passage | § 1506.10.5 (CPC) |
| Minimum residual pressure for graywater to toilets/urinals | 15 psi (103 kPa) at most remote outlet | § 1506.5 (CPC) |
| Maximum service pressure for on‑site treated nonpotable system outlets | Pressure reduced to ≤ 80 psi (552 kPa) where supply exceeds that | § 1506.10.4 (CPC) |
| Color coding / marking — potable piping | Green background with white lettering | § 601.3.1 (CPC) |
| Color coding / marking — nonpotable piping | Yellow background with black lettering (general nonpotable) | § 601.3.2 (CPC) |
| Color coding — alternate water sources | Purple background (graywater, reclaimed, rainwater markings per CPC) | § 601.3.3 (CPC) — wording examples (e.g., “CAUTION: NONPOTABLE GRAY WATER, DO NOT DRINK”) |
| Required system sign text (equipment rooms) | Example: “CAUTION: ON‑SITE TREATED NONPOTABLE GRAY WATER, DO NOT DRINK…” with 1 in (25.4 mm) letters for certain signs | § 1501.9 (CPC) |
| Cross‑connection testing required | Initial visual inspection and cross‑connection test before operation; potable may be temporarily connected for testing in certain cases | § 1502.3 and § 1502.3.2 (CPC) — exception allowing temporary potable connection for initial test file |
(Notes: CALGreen points users to Chapter 2 for definitions § 202 and to the CPC for technical implementation; the table entries reference the CPC sections CALGreen relies on for technical requirements.) file
Exceptions & special cases
- Temporary potable connection for initial cross‑connection testing of on‑site treated nonpotable systems is allowed by exception for the initial test only (must follow the CPC procedure) — see § 1502.3.2 and related exceptions file.
- Potable or reclaimed water may be used as make‑up for a non‑pressurized storage tank provided the inlet is protected by an air gap (exception in the CPC) — see § 1506.4 / related exceptions .
- Recycled water supply systems located within or as part of a building often have additional, separate provisions; CPC sections for recycled water (e.g., Chapter 15 sections on reclaimed water) include special exceptions and additional requirements (see § 1505.x series) .
- CALGreen voluntary measures (Appendices A4 / A5) encourage potable water elimination and alternate water use but explicitly require compliance with the California Plumbing Code when installing alternate water sources (see A4.303.2, A5.305.1) file.
If you need the verbatim CALGreen entry text for a specific defined term in § 202, the retrieved CALGreen excerpts here do not contain the full wording of those Chapter 2 definitions; for exact word‑for‑word definitions you should consult the full CALGreen Chapter 2 text (the code locates them at § 202) .
Common mistakes
- Assuming CALGreen’s “definitions” are spelled out in each water‑use chapter — CALGreen centralizes definitions in § 202 (Chapter 2) and often defers technical details to the California Plumbing Code; users sometimes read chapter text but miss that the operational definition is in Chapter 2 .
- Forgetting to follow CPC marking/labeling requirements for nonpotable piping and outlets (color, wording, and frequency of marking) — CPC § 601.3 must be followed when dual systems exist .
- Overlooking cross‑connection testing and the prohibition on direct connections between potable and nonpotable/recycled systems — CPC § 1502.3 and § 1506.4 explain required isolation, tests, and limited exceptions file.
- Using graywater for prohibited applications (spray irrigation, surface discharge) — graywater rules in CPC (referenced by CALGreen) forbid spray irrigation and direct discharge to storm drains or surface waters (see § 1503.1 and related) .
- Treating CALGreen Appendix guidance (voluntary measures) as standalone technical authority — even voluntary CALGreen sections require compliance with the CPC for the actual plumbing installation (e.g., rainwater catchment, graywater systems) .
Worked example — concrete scenario with numbers
Scenario: A new 50‑unit multiunit building will use an on‑site treated nonpotable graywater system to flush toilets and urinals in part of the building.
Steps and code checkpoints (with numbers):
- Definitions and scope: Confirm graywater and alternate water source terms are applied per CALGreen Chapter 2 (§ 202) and the building follows CALGreen Division 5.3 water‑efficiency provisions referencing the Plumbing Code file.
- Permits & plans: Submit full plumbing plans to the Authority Having Jurisdiction before issuing permits (CPC § 1506.2) — no system activation before approval .
- Filtration & pressure: Provide a filter that passes no particles larger than 100 µm for graywater intended for toilets/urinals (CPC § 1506.10.5) and ensure at least 15 psi (103 kPa) residual pressure at the highest, most remote outlet (CPC § 1506.5) .
- Pipe separation: If running treated nonpotable and potable piping in the same trench, maintain 12 inches (305 mm) vertical/horizontal separation (or 60 inches (1524 mm) if materials aren't acceptable) and install potable piping at a higher elevation — see § 1502.4 (CPC) .
- Marking and signs: Mark nonpotable/alternate water piping with purple labeling and the required wording such as “CAUTION: ON‑SITE TREATED NONPOTABLE GRAY WATER, DO NOT DRINK” (CPC § 601.3.3) and post the equipment room sign required by § 1501.9 (CPC) file.
- Cross‑connection test: Before initial operation perform the visual inspection and initial cross‑connection test with the Authority Having Jurisdiction (CPC § 1502.3.1 and § 1502.3.2); potable water may only be temporarily connected to the nonpotable system for that initial test under the CPC exception and in accordance with testing procedures file.
- Operation & maintenance: Maintain the system per manufacturer and CPC maintenance tables (inspections every 3 months to 12 months depending on the item) — see CPC maintenance/inspection frequency tables (e.g., § 1505.16) .
Outcome: If you size and install filters and pumps so that toilets receive ≥15 psi residual and you follow the 100 µm filtration, 12 in / 60 in separations, purple marking, signage, and cross‑connection testing above, you meet the principal CALGreen/CPC requirements for on‑site treated nonpotable graywater used for toilet flushing as referenced in CALGreen (definitions in § 202) and implemented through the CPC chapters cited by CALGreen file.
Related provisions (CALGreen / referenced CPC sections)
- CALGreen Chapter 2 — § 202 (Definitions) — location of defined terms referenced throughout CALGreen (CALGreen Table of Contents) .
- CALGreen Division 5.3 — § 5.302.1 (Definitions reference to Chapter 2) and water‑efficiency provisions that call out definitions such as POTABLE WATER and GRAYWATER .
- CALGreen Appendix A4 — A4.303.2 (Alternate water sources for nonpotable applications — requires CPC compliance) .
- CALGreen Appendix A5 — A5.305.1 (Nonpotable water systems must comply with the California Plumbing Code) .
- California Plumbing Code (as referenced by CALGreen): § 1501 – § 1510 series on Alternate Water Sources / Graywater / Reclaimed Water (technical requirements, separation, testing) — e.g., § 1502.3 (cross‑connection testing), § 1506.5 (pressure), § 1506.10.5 (filter), § 1502.4 (separation) filefile.
- California Plumbing Code — § 601.3 (identification color/marking for potable, nonpotable, and alternate water systems) .
If you want, I can:
- Pull the verbatim CALGreen § 202 definitions (exact text) if you can provide the full CALGreen Chapter 2 file, or I can search the provided files again for any missing Chapter 2 snippets.
- Produce a one‑page checklist (permit plan checklist) tailored to a graywater toilet‑flushing system that you can drop into plan submittals.
Code references
Grounded in the retrieved California Green Building Standards Code (CALGreen) — click a citation to read the verbatim passage:
CALGreen § 0.293 High relevance — show source text
For SI units: 1000 British thermal units per hour = 0.293 kW
1203.3 Tankless Water Heaters. Tankless water heaters used in space-heating applications shall be rated by the manufacturer for space-heating applications, and the output performance shall be determined by the temperature rise and flow rate of water through the unit. The ratings shall be expressed by the water temperature rise at a given flow rate. Manufacturer’s flow rates shall not be exceeded.
1204.0 Identification of Potable and Nonpotable Water Systems. 1204.1 General. In buildings where potable water and nonpotable water systems are installed, each system shall be clearly identified in accordance with Section 1204.2 through Section 1204.7.
1204.2 Color and Information. Each system shall be identified with a colored pipe or band and coded with paint, wraps, and materials compatible with the piping. 1204.3 Potable Water. Potable water systems shall be identified with a green background with white lettering. The minimum size of letters and length of the color field shall be in accordance with Table 1204.3.
TABLE 1204.3
MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS
OUTSIDE DIAMETER OF
PIPE OR COVERING
(inches)MINIMUM LENGTH
OF COLOR FIELD
(inches)MINIMUM SIZE OF
LETTERS
(inches)1_/2 to 11/_4 8 1_/_2
11_/_2 to 28 3_/_4
21_/_2 to 612 11_/_4
8 to 1024 21_/_2
over 1032 31_/_2 For SI units: 1 inch = 25.4 mm
TABLE 1203.2
WATER HEATERS
1204.4 Nonpotable Water. Nonpotable water systems shall have a yellow background with black uppercase lettering, with the words: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 1204.3.
TABLE 1204.3
MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS
For SI units: 1 inch = 25.4 mm
1204.5 Location of Piping Identification. The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.
1204.6 Flow Directions. Flow directions shall be indicated
on the system.
1204.7 Heat Transfer Fluid. Hydronic piping shall be identified with an orange background with black uppercase lettering, with the words “CAUTION: HEAT TRANSFER FLUID, DO NOT DRINK.” Each hydronic system shall be identified to designate the fluid being conveyed. The minimum size of the letters and length of the color field shall comply with Table 1204.3.
Each outlet on the hydronic piping system shall be posted with black uppercase lettering as follows:
“CAUTION: HEAT TRANSFER FLUID, DO NOT DRINK.”
CALGreen § 601.2.1.1 High relevance — show source text
601.2.1.1 Approved Submeters. [HCD 1] Sub- meters (or meters) shall be approved in accordance with the Business and Professions Code, Division 5.
601.2.1.2 Submeter Testing. [HCD 1] Submeter (or meter) testing shall be in accordance with the California Code of Regulations, Title 4, Division 9, Chapter 3, Article 1; Civil Code, Division 3, Part 4, Title 5; and Business and Professions Code, Divi- sion 5.
601.2.2 Hot and Cold Water Required. In occupancies where plumbing fixtures are installed for private use, hot water shall be required for bathing, washing, laundry, cooking purposes, dishwashing or maintenance. In occupancies where plumbing fixtures are installed for public use, hot water shall be required for bathing and washing purposes. This requirement shall not supersede the requirements for individual temperature control limitations for public lavatories and public and private bidets, bathtubs, whirlpool bathtubs, and shower control valves.
601.3 Identification of a Potable and Nonpotable Water System. In buildings where potable water and nonpotable water systems are installed, each system shall be clearly identified in accordance with Section 601.3.1 through Section 601.3.5.
601.3.1 Potable Water. Green background with white lettering.
601.3.2 Color and Information. Each system shall be identified with a colored pipe or band and coded with paints, wraps, and materials compatible with the piping.
Except as required by Section 601.3.3, nonpotable water systems shall have a yellow background with black uppercase lettering, with the words “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 601.3.2.
[HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601 for all nonpotable water
systems.
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WATER SUPPLY AND DISTRIBUTION
FIGURE 601
INTERNATIONAL SYMBOL
The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.
601.3.3 Alternate Water Sources. Alternate water source systems shall have a purple (Pantone color No. 512, 522C, or equivalent) background with uppercase lettering and shall be field or factory marked as follows:
(1) Gray water systems shall be marked in accordance with this section with the words “CAUTION: NONPOTABLE GRAY WATER, DO NOT DRINK” in black letters.
CALGreen § 1502.3.2. High relevance — show source text
(2) A potable water supply may be connected temporarily for the initial cross-connection test of the on-site treated non- potable gray water system as provided in Section 1502.3.2. 1506.5 Water Pressure. On-site treated non-potable gray water systems supplying water to water closets, urinals, and trap primers shall be capable of delivering not less than 15 pounds-force per square inch (psi) (103 kPa) residual pressure at the highest and most remote outlet served. Where the
TABLE 1505.16 MINIMUM RECLAIMED (RECYCLED) WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY
DESCRIPTION MINIMUM FREQUENCY*
Inspect and clean filters and screens, and replace (where necessary). [Every 3 months.]
Inspect pumps and verify operation. After initial installation and every 12 months thereafter.
Inspect valves and verify operation. After initial installation and every 12 months thereafter.
Inspect pressure tanks and verify operation. After initial installation and every 12 months thereafter.
Clear debris from and inspect storage tanks, locking devices, and verify operation.
After initial installation and every 12 months thereafter.
Inspect caution labels and marking. After initial installation and every 12 months thereafter.
* Note: Frequency is as described in this table, or more frequently as required by manufacturer’s instructions and/or the Authority Having Jurisdiction.
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ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS
1506.10.3 Deactivation and Drainage. The on-site treated nonpotable gray water system and the potable water system within the building shall be provided with the required appurtenances (e.g., valves, air/vacuum relief valves, etc.) to allow for deactivation or drainage as required for a cross-connection test in accordance with Section 1502.3.
1506.10.4 Near Underground Potable Water Pipe. On-site treated nonpotable gray water pipes 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 piping materials do not meet 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 on-site treated nonpotable gray water piping. 1506.10.5 Required Filters. A filter permitting the passage of particulates no larger than 100 microns (100 µm) shall be provided for on-site treated nonpotable gray water supplied to water closets, urinals, trap primers, and drip irrigation system s . 1506.10.6 Disinfection. Where the intended use of onsite treated nonpotable gray water requires disinfec- tion and/or other treatment, on-site treated nonpotable gray water shall be disinfected as needed to ensure the required water quality is obtained at the point of use. Where chlorine is used for disinfection or treatment, water shall be tested for residual chlorine in accordance with ASTM D1253.
CALGreen § 1502.3.1 High 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.
CALGreen § 1506.6 Medium relevance — show source text
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water pressure in the on-site treated non-potable gray water supply system within the building exceeds 80 psi (552 kPa), a pressure reducing valve reducing the pressure to 80 psi (552 kPa) or less to water outlets in the building shall be installed.
1506.6 Initial Cross-Connection Test. A cross-connection test is required in accordance with Section 1502.3. Before the building is occupied or the system is activated, the installer shall perform the initial cross-connection test in the presence of the Authority Having Jurisdiction and other authorities having jurisdiction. The test shall be ruled successful by the Authority Having Jurisdiction before final approval is granted. 1506.7 On-Site Treated Nonpotable Gray Water Sys- tem Materials. On-site treated nonpotable gray water supply, and distribution system materials shall comply with the requirements of this code for potable water supply and distribution systems unless otherwise provided for in this section.
1506.8 On-Site Treated Nonpotable Gray Water Devices and Systems. Devices or equipment used to treat on-site treated nonpotable gray water to maintain the minimum water quality requirements determined by the Authority Having Jurisdiction shall be listed and labeled (third-party certified) by a listing agency (accredited conformity assessment body) or approved for the intended application. Devices or equipment used to treat on-site treated nonpotable gray water for use in the water closet and urinal flushing, surface irrigation, and similar applications shall comply with IAPMO IGC 324, NSF/ANSI 350 or approved by the Authority Having Jurisdiction. 1506.9 On-Site Treated Nonpotable Gray Water Sys- tem Color and Marking Information. On-site treated nonpotable gray water systems shall have a colored background and marking information in accordance with Section 601.3 of this code.
1506.10 Design and Installation. The design and installation of on-site treated nonpotable gray water systems shall be in accordance with Section 1506.10.1 through Section 1506.10.6 .
1506.10.1 Listing Terms and Installation Instruc- tions. On-site treated nonpotable gray water systems shall be installed in accordance with the terms of its listing and the manufacturer’s installation instructions. 1506.10.2 Minimum Water Quality. [BSC-CG & HCD 1] On-site treated nonpotable gray water supplied to toilets or urinals or for other uses in which it is sprayed or exposed shall be disinfected. Acceptable disinfection methods shall include chlorination, ultraviolet sterilization, ozone, or other methods as approved by the Authority Having Jurisdiction. The minimum water quality for on-site treated nonpotable gray water systems shall meet the applicable water quality requirements for the intended applications as determined by the public health Authority Having Jurisdiction. In the absence of local water quality requirements for on-site treated nonpotable gray water, the requirements of IAPMO IGC 324 or NSF/ANSI 350 shall apply.
2025 CALIFORNIA PLUMBING CODE 323
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CALGreen § 1.11.0. Medium relevance — show source text
0||||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 29
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30 2025 CALIFORNIA PLUMBING CODE
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CHAPTER 2
DEFINITIONS
201.0 General.
201.1 Applicability. For the purpose of this code, the following terms have the meanings indicated in this chapter.
No attempt is made to define ordinary words, which are used in accordance with their established dictionary meanings, except where a word has been used loosely, and it is necessary to define its meaning as used in this code to avoid misunderstanding.
202.0 Definition of Terms.
202.1 General. The definitions of terms are arranged alphabetically according to the first word of the term.
203.0 – A –
ABS. Acrylonitrile-butadiene-styrene. Accepted Engineering Practice. That which conforms to technical or scientific-based principles, tests, or standards that are accepted by the engineering profession. Accessible. Where applied to a fixture, connection, appliance, or equipment, “accessible” means having access thereto, but which first may require the removal of an access panel, door, or similar obstruction. Accessible, Readily. Having a direct access without the necessity of removing a panel, door, or similar obstruction. Accessory Dwelling Unit. [HCD 1 & HCD 2] An attached or detached residential dwelling unit that provides complete independent living facilities for one or more per- sons and is located on a lot with a proposed or existing pri- mary residence. Accessory dwelling units shall include permanent provisions for living, sleeping, eating, cooking, and sanitation on the same parcel as the single-family or mul- tifamily dwelling is or will be situated. (See Government Code Section 65852.2.) Air Break. A physical separation which may be a low inlet into the indirect waste receptor from the fixture, appliance, or device indirectly connected. Air Gap, Drainage. The unobstructed vertical distance through the free atmosphere between the lowest opening from a pipe, plumbing fixture, appliance, or appurtenance conveying waste to the flood-level rim of the receptor. Air Gap, Water Distribution. The unobstructed vertical distance through the free atmosphere between the lowest opening from a pipe or faucet conveying potable water to the flood-level rim of a tank, vat, or fixture.
Alternate Water Source. Nonpotable source of water that includes but not limited to gray water, on-site treated nonpotable water, on-site treated nonpotable gray water, rainwater, and reclaimed (recycled) water. Anchors. See Supports. Anodeless Riser. An assembly of steel-cased plastic pipe used to make the transition between plastic piping installed
underground and metallic piping installed aboveground.
[NFPA 54:3.3.3] **Appliance.
CALGreen § 1506.10.3 Medium relevance — show source text
1506.10.3 Deactivation and Drainage. The on-site treated nonpotable gray water system and the potable water system within the building shall be provided with the required appurtenances (e.g., valves, air/vacuum relief valves, etc.) to allow for deactivation or drainage as required for a cross-connection test in accordance with Section 1502.3.
1506.10.4 Near Underground Potable Water Pipe. On-site treated nonpotable gray water pipes 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 piping materials do not meet 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 on-site treated nonpotable gray water piping. 1506.10.5 Required Filters. A filter permitting the passage of particulates no larger than 100 microns (100 µm) shall be provided for on-site treated nonpotable gray water supplied to water closets, urinals, trap primers, and drip irrigation system s . 1506.10.6 Disinfection. Where the intended use of onsite treated nonpotable gray water requires disinfec- tion and/or other treatment, on-site treated nonpotable gray water shall be disinfected as needed to ensure the required water quality is obtained at the point of use. Where chlorine is used for disinfection or treatment, water shall be tested for residual chlorine in accordance with ASTM D1253.
1506.11 Valves. Valves, except fixture supply control valves, shall be equipped with a locking feature. 1506.12 Signs. Signs in buildings using on-site treated nonpotable gray water shall comply with Section s 1501.9, 1501.9.1 and 1501.9.2 and applicable requirements of the Cal- ifornia Building Code . 1506.13 Inspection and Testing. On-site treated nonpotable gray water systems shall be inspected and tested in accordance with Section 1502.1 and/or as required by the Authority Having Jurisdiction .
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water pressure in the on-site treated non-potable gray water supply system within the building exceeds 80 psi (552 kPa), a pressure reducing valve reducing the pressure to 80 psi (552 kPa) or less to water outlets in the building shall be installed.
1506.6 Initial Cross-Connection Test. A cross-connection test is required in accordance with Section 1502.3. Before the building is occupied or the system is activated, the installer shall perform the initial cross-connection test in the presence of the Authority Having Jurisdiction and other authorities having jurisdiction. The test shall be ruled successful by the Authority Having Jurisdiction before final approval is granted. 1506.7 On-Site Treated Nonpotable Gray Water Sys- tem Materials. On-site treated nonpotable gray water supply, and distribution system materials shall comply with the requirements of this code for potable water supply and distribution systems unless otherwise provided for in this section.
1506.8 On-Site Treated Nonpotable Gray Water **Devices and Systems.
CALGreen § 1.12 Medium relevance — show source text
Includes water closets with an effective flush rate of 1.12 gallons or less when tested per ASME A 112.19.2 and ASME A 112.19.14.
2. See Table A5.503.2.2 for additional notes and references.
3. Where complying faucets are unavailable, aerators rated at 0.35 gpm or other means may be used to achieve reduction.
4. Floor-mounted urinals @ 0.5 GPF or wall-mounted urinals @ 0.125 GPF.|A5.303.2.3.2 Tier 2 – 20-percent savings. A schedule of plumbing fixtures and fixture fittings that will reduce the overall use of potable water within the building by 20 percent shall be provided. A calculation demonstrating a 20-percent reduction in the building “water use baseline” as established in Table A5.303.2.2 shall be provided. A5.303.2.3.3 25-percent savings. A schedule of plumbing fixtures and fixture fittings that will reduce the overall use of potable water within the building by 25 percent shall be provided. A calculation demonstrating a 25-percent reduction in the building “water use baseline” as established in Table A5.303.2.2 shall be provided. A5.303.2.3.4 Nonpotable water systems for indoor use. Utilizing nonpotable water systems (such as captured rainwater, treated graywater and recycled water) intended to supply water closets, urinals and other allowed uses, may be used in the calculations demonstrating the 12-, 20- or 25-percent reduction. The nonpotable water systems shall comply with the current edition of the California Plumbing Code.
A5.303.3 Appliances and fixtures for commercial application. Appliances and fixtures shall meet the following:
- Clothes washers shall have a maximum Water Factor (WF) that will reduce the use of water by 10 percent below the California Energy Commissions’ WF standards for commercial clothes washers located in Title 20 of the California Code of Regulations.
- Dishwashers shall meet the following water use standards: a. Residential—ENERGY STAR.
i. Standard Dishwashers – 4.25 gallons per cycle. ii. Compact Dishwashers – 3.5 gallons per cycle. b. Commercial—Shall be in accordance with ENERGY STAR requirements. Refer to Table A5.303.3. 3. Ice makers shall be air cooled.
- Food steamers shall be connectionless or boilerless – and shall consume no more than 2 gallons of water per pan per hour, including condensate water, for batch type steamers, and no more than 5 gallons of water per pan per hour, including condensate water, for cook to order steamers.
- The use and installation of water softeners that discharge to the community sewer system may be limited or prohibited by local agencies if certain conditions are met.
- Combination ovens shall use a maximum of 1.5 gallons of water per hour per pan, including condensate water.
- Food waste pulping systems shall use no more than 2 gpm of potable water. 7.1. Note: potable water excludes on-site graywater use, such as dishwasher discharge water.
|TABLE A5.303.
CALGreen § 1505.7 Medium relevance — show source text
(2) Reclaimed (recycled) water systems for outdoor applications shall be marked in accordance with this section with the words: “CAUTION: NONPOTABLE RECLAIMED (RECYCLED) WATER, DO NOT DRINK” in black letters.
(3) On-site treated water systems shall be marked in accordance with this section with the words: “CAU TION: ON-SITE TREATED NONPOTABLE WATER, DO NOT DRINK” in black letters.
(4) Rainwater catchment systems shall be marked in accordance with this section with the words: “CAU TION: NONPOTABLE RAINWATER, DO NOT DRINK” in black letters.
Exception: [DWR] For recycled water supply systems that are within or a part of a building, the provisions of Section 1505.7 shall apply.
TABLE 601.3.2
MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS
OUTSIDE DIAMETER
OF PIPE OR
COVERING
(inches)MINIMUM LENGTH OF
COLOR FIELD
(inches)MINIMUM SIZE OF
LETTERS
(inches)
1⁄2 to 11⁄48 1⁄2
11⁄2 to 28 3⁄4
21⁄2 to 612 11⁄4
8 to 1024 21⁄2
Over 1032 31⁄2 For SI units: 1 inch = 25.4 mm
601.3.4 Fixtures. Where vacuum breakers or backflow preventers are installed with fixtures listed in Chapter 17, identification of the discharge side shall be permitted to be omitted.
601.3.5 Outlets. Each outlet on the nonpotable water line that is used for special purposes shall be posted with black uppercase lettering as follows: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”
601.4 Schools of Cosmetology and Cosmetological Establishments. [CA]
601.4.1 Hot- and Cold-Running Water. At least one sink with hot-and cold-running water shall be provided in each work area or workroom where hairdressing is performed in each school and establishment. 601.4.2 Handwashing Facilities. Each school and establishment shall provide adequate handwashing facil- ities, including hot-and cold-running water, located within or adjacent to the toilet room or rooms in accor- dance with Table 422.1.
601.4.3 Drinking Water. Each school and establishment shall supply potable drinking water convenient to students, patrons and employees. Approved sanitary drinking foun- tains shall be installed and so regulated that a jet of at least 2 inches (51 mm) shall be constantly available.
601.5 Meat and Poultry Processing Plants. [AGR] Except as provided in Section 601.5.4, the water supply shall be ample and potable, with adequate pressure and facilities for its distribution in the plant, and its protection against con- tamination and pollution.
CALGreen § 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.
CALGreen § 1501.9. Medium relevance — show source text
“TO CONSERVE WATER, THIS BUILDING USES ON-SITE TREATED NONPOTABLE GRAYWATER TO
FLUSH TOILETS AND URINALS.”
1501.9. 2 Equipment Room Signs. Each room containing on-site treated nonpotable gray water equipment shall have a sign posted in a location that is visible to anyone working on or near nonpotable gray water equipment with the following wording in 1 inch (25.4 mm) letters:
“CAUTION: ON-SITE TREATED NONPOTABLE GRAY-
WATER, DO NOT DRINK. DO NOT CONNECT TO DRINKING WATER SYSTEM. NOTICE: CONTACT
BUILDING MANAGEMENT BEFORE PERFORMING
ANY WORK ON THIS WATER SYSTEM.”
1501.10 System Controls. Controls for pumps, valves, and other devices that contain mercury that come in contact with alternate water source water supply shall not be permitted.
1502.0 Inspection and Testing.
1502.1 General. Alternate water source systems shall be inspected and tested in accordance with Section 1502.2 through Section 1502.3.3, and/or as required by the Author- ity Having Jurisdiction .
Exception: [DWR] Recycled water supply systems that are within or a part of a building shall comply with Section 1505.14.
1502.2 Supply System Inspection and Test. Alternate water source systems shall be inspected and tested in accordance with this code for testing of potable water piping.
1502.3 Cross-Connection Inspection and Testing. An initial visual inspection and initial cross-connection test shall be performed on both the potable and alternate water source systems before the initial operation of the alternate water source system. During an initial or subsequent cross-con- nection test, the potable and alternate water source system shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection in accor dance with Section 1502.3.1 through Section 1502.3.3 .
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1502.3.1 Visual System Inspection. Before commencing the cross-connection testing, a dual system inspection shall be conducted by the Authority Having Jurisdiction and other authorities having jurisdiction as follows:
(1) Meter locations of the alternate water source and potable water lines shall be checked to verify that no modifications were made and that no cross-con nections are visible.
(2) Pumps and equipment, equipment room signs and exposed piping in equipment room shall be checked.
(3) Valves shall be checked to ensure that the valve lock seals are still in place and intact. Valve control door signs shall be checked to verify that no signs have been removed.
1502.3.2 Cross-Connection Test. A cross-connec- tion test shall be performed in the presence of the Authority Having Jurisdiction or other authorities having jurisdiction to determine whether a cross-connection has occurred as follows:
(1) The potable water system shall be activated and pressurized. The alternate water source system shall be shut down, depressurized, and drained.
CALGreen § 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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(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.
CALGreen § 1501.1.1 High relevance — show source text
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. [BSC-CG, HCD 1 & DWR] It shall be unlawful for a person to construct, install, alter, or cause to be constructed, installed, or altered an alternate water source system in a building or on its premise s without first obtaining a permit to do such work from the Authority Having Jurisdiction. No changes or connections shall be made to either the alternate water source system or the potable water system within a site containing an alternate water source system without approval by the Authority Having Jurisdiction. Exception: [BSC-CG & HCD 1] A construction permit shall not be required for a clothes washer system meeting the requirements of Section 1503.1.1. 1501.4 Component Identification. System components shall be properly identified as to the manufacturer. 1501.5 Maintenance and Inspection. [BSC-CG, HCD 1 & DWR] Alternate water source systems and components shall be inspected and maintained in accordance with the
manufacturer’s recommendations and/or as required by the Authority Having Jurisdiction. [BSC-CG] Where no manu- facturer’s recommendations exist, additional recommenda- tions are listed in Table 1501.5 .
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.
CALGreen § 14877.3. Medium relevance — show source text
** 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.
(2) A potable water supply may be connected temporarily for the initial cross-connection test of the on-site treated non- potable gray water system as provided in Section 1502.3.2. 1506.5 Water Pressure. On-site treated non-potable gray water systems supplying water to water closets, urinals, and trap primers shall be capable of delivering not less than 15 pounds-force per square inch (psi) (103 kPa) residual pressure at the highest and most remote outlet served. Where the
TABLE 1505.16 MINIMUM RECLAIMED (RECYCLED) WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY
DESCRIPTION MINIMUM FREQUENCY*
Inspect and clean filters and screens, and replace (where necessary). [Every 3 months.]
Inspect pumps and verify operation. After initial installation and every 12 months thereafter.
Inspect valves and verify operation. After initial installation and every 12 months thereafter.
Inspect pressure tanks and verify operation. After initial installation and every 12 months thereafter.
Clear debris from and inspect storage tanks, locking devices, and verify operation.
After initial installation and every 12 months thereafter.
Inspect caution labels and marking. After initial installation and every 12 months thereafter.
* Note: Frequency is as described in this table, or more frequently as required by manufacturer’s instructions and/or the Authority Having Jurisdiction.
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CALGreen § 303.1 Medium relevance — show source text
2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A4-11
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX A4-12 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
A4 RESIDENTIAL VOLUNTARY MEASURES
DIVISION A4.3 – WATER EFFICIENCY AND CONSERVATION
SECTION A4.301—GENERAL (RESERVED)
SECTION A4.302—DEFINITIONS (RESERVED)
SECTION A4.303—INDOOR WATER USE
A4.303.1 Kitchen faucets. The maximum flow rate of kitchen faucets shall not exceed 1.5 gallons per minute at 60 psi. Kitchen faucets may temporarily increase the flow above the maximum rate, but not to exceed 2.2 gallons per minute at 60 psi, and must default to a maximum flow rate of 1.5 gallons per minute at 60 psi.
Note: Where complying faucets are unavailable, aerators or other means may be used to achieve reduction.
A4.303.2 Alternate water sources for nonpotable applications. Alternate nonpotable water sources are used for indoor potable water reduction. Alternate nonpotable water sources shall be installed in accordance with the California Plumbing Code.
A4.303.3 Appliances. Install at least one qualified ENERGY STAR dishwasher or clothes washer.
Note: See Section A5.303.3 for nonresidential dishwashers and clothes washers.
A4.303.4 Nonwater urinals and waterless toilets. Nonwater urinals or composting toilets are installed.
Where approved, nonwater urinals with drain cleansing action (formerly hybrid urinals), as defined in Chapter 2, shall be considered nonwater urinals.
A4.303.5 Hot water recirculation systems. One- and two-family dwellings shall be equipped with a demand hot water recirculation system, as defined in Chapter 2. The demand hot water recirculation system shall be installed in accordance with the California Plumbing Code, California Energy Code and the manufacturer’s installation instructions.
SECTION A4.304—OUTDOOR WATER USE
A4.304.1 Rainwater catchment systems. An approved rainwater catchment system is designed and installed to use rainwater generated by at least 65 percent of the available roof area. Rainwater catchment systems shall be designed and installed in accordance with the California Plumbing Code.
A4.304.2 Potable water elimination. When landscaping is provided and as allowed by local ordinance, a water efficient landscape irrigation design that eliminates the use of potable water beyond the initial requirements for plant installation and establishment shall be provided. Methods used to accomplish the requirements of this section shall comply with the requirements of the California Building Standards Code and shall include, but not be limited to, the following:
- Use of captured rainwater.
- Use of recycled water.
- Water treated for irrigation purposes and conveyed by a water district or public entity.
- Use of graywater.
- Use of drought tolerant plants.
A4.304.3 Landscape water meters. For new water service connections, landscaped irrigated areas less than 5,000 square feet shall be provided with separate submeters or metering devices for outdoor potable water use.
CALGreen § 1505.16 Medium 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.
CALGreen § 1503.2.2 Medium relevance — show source text
Exception: It is not the intent of this section to require that all gray water must be handled by an irrigation field or disposal field. It is acceptable for excess gray water to be diverted to the building sewer through a diverter valve or overflow drain as permitted in this chapter. 1503.2.2 Diversion. The gray water system shall connect to the sanitary drainage system downstream of fixture traps and vent connections through an approved diverter valve. The diverter valve shall be installed in a readily accessible location and clearly indicate the direction of flow.
Exception: [HCD 1] A clothes washer system in com- pliance with Section 1503.1.1. 1503.2.3 Backwater Valves. Gray water drains subject to backflow shall be provided with a backwater valve at the point of connection to the building sewer system, so located as to be accessible for inspection and maintenance. 1503.3 Connections to Potable and Reclaimed (Recy- cled) Water Systems. Gray water systems shall have no direct connection to a potable water supply, on-site treated nonpotable gray water supply, or reclaimed (recycled) water sup- ply systems.
Exceptions:
(1) Potable water, on-site treated nonpotable gray water, reclaimed (recycled) water , or rainwater is permitted to be used as makeup water for a non-pressurized storage tank provided the connection is protected by an air gap in accordance with this code.
(2) A potable water supply may be connected temporarily for the initial cross-connection test of the untreated gray- water system as required in Section 1502.3.2. 1503.4 Location. No gray water system or part thereof shall be located on a lot other than the lot that is the site of the building or structure that discharges the gray water, nor shall a gray water system or part thereof be located at a point having less than the minimum distances indicated in Table 1503.4.
Exception: When there exists a lawfully recorded perpetual and exclusive covenant to an easement appurtenant and right-of- way between adjoining land-owners of two or more contiguous lots to discharge gray water from one lot to an adjoining lot. 1503.5 Plot Plan Submission. No permit for a gray water system shall be issued until a plot plan with data satisfactory to the Authority Having Jurisdiction has been submitted and approved. Exception: [HCD 1] A construction permit shall not be required for a clothes washer system in compliance with Sec- tion 1503.1.1.
1503.6 Prohibited Location. Where there is insufficient lot area or inappropriate soil conditions for adequate absorption, no gray water system shall be permitted.
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TABLE 1503.4 LOCATION OF GRAY WATER SYSTEM [7]
CALGreen § 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.
CALGreen § 1601.10 Medium relevance — show source text
1601.10 Separation Requirements. Underground rainwater catchment service piping shall be separated from the building sewer in accordance with Section 609.2. Treated nonpotable water pipes 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 meet 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. 1601.11 Abandonment. Rainwater catchment systems that are no longer in use, or fail to be maintained in accordance with Section 1601.5, shall be abandoned. Abandonment shall comply with Section 1601.11.1 and Section 1601.11.2.
1601.11.1 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. 1601.11.2 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. 1601.12 Sizing. Unless otherwise provided for in this chapter, rainwater catchment piping shall be sized in accordance with Chapter 6 for sizing potable water piping.
1602.0 Nonpotable Rainwater Catchment Systems. 1602.1 General. The installation, construction, alteration, and repair of rainwater catchments systems intended to supply uses such as water closets, urinals, trap primers for floor drains and floor sinks, irrigation, industrial processes, water features, cooling tower makeup and other uses shall be approved by the Authority Having Jurisdiction. Rainwater catchment systems for collecting precipitation from rooftops shall comply with ARCSA/ASPE/ANSI 63. 1602.2 Plumbing Plan Submission. No permit for a rainwater catchment system shall be issued until complete plumbing plans, with data satisfactory to the Authority Having Jurisdiction, have been submitted and approved. 1602.3 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. 1602.4 Connections to Potable or Reclaimed (Recy- cled) Water Systems. Rainwater catchment systems shall have no direct connection to a potable water supply or alternate water source system. Exceptions: (1) Potable water, on-site treated nonpotable gray water, or reclaimed (recycled) water is permitted to be used as makeup water for a rainwater catchment system provided the connection is protected by an air gap in accordance with this code.
(2) A potable water supply may be connected temporarily for the initial cross-connection test of the rainwater catchment system as required in Section 1605.3.2. 1602.5 Initial Cross-Connection Test. Where a portion of a rainwater catchment system is installed within a building, a cross-connection test is required in accordance with Section 1605.3.
Frequently asked questions
What if CALGreen and the Plumbing Code seem to differ about a term?
CALGreen points you to Chapter 2 for definitions and then to the California Plumbing Code for plumbing‑system technical rules. Where CALGreen calls for plumbing rules it explicitly requires compliance with the CPC; follow the CPC technical provisions cited by CALGreen and consult the AHJ if a local amendment applies file.
Where exactly are the CALGreen definitions located?
CALGreen places defined terms in Chapter 2 — § 202 (Definitions) — and other CALGreen sections reference those Chapter 2 terms (the retrieved CALGreen excerpts show the Chapter 2 index but did not include the full § 202 text in the files provided here) .
Can graywater be used for spray irrigation?
No — graywater used for irrigation is generally prohibited from spray irrigation and surface discharge per the graywater rules in the Plumbing Code referenced by CALGreen (see CPC § 1503.1 and related) .
How must nonpotable piping be marked?
Follow the CPC marking requirements: green for potable (§ 601.3.1), yellow for general nonpotable (§ 601.3.2), purple for alternate/recycled water (with specific wording such as “CAUTION: NONPOTABLE…”) (§ 601.3.3) — CALGreen requires compliance with these marking rules via the CPC file.
Is a cross‑connection test really required?
Yes — an initial visual and cross‑connection test must be performed before operation; CPC § 1502.3 describes the visual inspection and § 1502.3.2 the cross‑connection test procedure. CALGreen requires compliance with the CPC for alternate water systems .
More in California Green Building Standards Code (CALGreen)
- Administration (Chapter 1)
- Nonresidential Voluntary Measures (Appendix A5 — divisions A5.1–A5.6, electives & verification)
- Residential Mandatory Measures — Planning & Design; Energy; Water; Materials; Environmental Quality (Chapter 4)
- Definitions (Chapter 2)
- Voluntary Standards for Health Facilities (Appendix A6 / OSHPD guidance)
- Green Building – scope, mixed occupancies, phased projects (Chapter 3)
- Residential Voluntary Measures (Appendix A4 — divisions A4.1–A4.6, tiers & model ordinance)
- Nonresidential Mandatory Measures — Planning & Design; Energy; Water; Materials; Environmental Quality (Chapter 5)
- Compliance verification, construction documents & checklists (Section 102, Chapter 7, Appendix checklists)
- Referenced Organizations and Standards (Chapter 6)
- Voluntary Tiers and CALGreen Tier 1 / Tier 2 (performance tiers, thresholds)
- Installer and Special Inspector Qualifications (Chapter 7)
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