CPC · California Plumbing Code

What cross‑connection tests and inspections are required?

Q: How long must the non‑pressurized system remain empty during the test?

The AHJ sets the period case‑by‑case, but in no case shall it be less than 1 hour . § 1605.3.2 .

Q: Can I temporarily connect potable water to the rainwater system to do the test?

Yes — a temporary potable connection is permitted for the initial cross‑connection test only; it must be disconnected at the conclusion of that test. See the exception in § 1602.4 and the procedures in § 1605.3.2 .

Q: How often must cross‑connection testing/inspection occur after initial approval?

Minimum requirement is after initial installation and every 12 months thereafter (unless the AHJ sets a different schedule). See Table 1601.5 / § 1601.5 .

Before a rainwater catchment system inside a building can be used, the installer must run an AHJ‑witnessed visual inspection and cross‑connection test that isolates the potable and rainwater systems; the non‑pressurized system must be empty for at least one hour during testing, any discovered cross‑connection must be disconnected and the potable system disinfected (50 ppm, 24 hrs) and bacteriologically cleared, and routine rechecks are required (minimum annually).

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Last reviewed: July 6, 2026

What the code requires — plain English

Before a rainwater catchment system that is installed inside a building may be put into service, the installer must perform an initial cross‑connection test in the presence of the Authority Having Jurisdiction (AHJ). The potable and rainwater systems must be isolated and both visually inspected and tested to confirm no cross‑connection exists. These requirements are stated at § 1602.5 and in the cross‑connection inspection/testing rules at § 1605.3 and § 1605.3.2.

The single most important rule: the AHJ must witness an initial visual inspection and an isolation test of the potable and rainwater systems, and the systems must show no cross‑flow before final approval. § 1602.5, § 1605.3.

Requirements in detail

Who must be present and when

The AHJ (or its authorized representative) must be present for the initial cross‑connection test and any subsequent tests in which a cross‑connection is suspected. § 1602.5, § 1605.3.2.

Two steps required before initial operation

A visual system inspection of both systems (potable and rainwater) prior to testing. § 1605.3.1.
- Inspect pumps, equipment, room signage, exposed piping, valves, meter locations (as applicable).
A cross‑connection test performed with one system pressurized while the other is shut down, drained, and observed for unintended flow. § 1605.3.2.

Minimum test conditions and timing

The potable system is pressurized while the rainwater system is empty (and vice versa when required by test procedure). § 1605.3.2.
The AHJ determines the required test duration case‑by‑case, but the rainwater (or alternate/nonpotable) system shall remain depressurized for no less than 1 hour during the portion of the test when the other system is pressurized. § 1605.3.2.

What to do if a cross‑connection is found

The discovery procedure must be performed in the presence of the AHJ and includes:

Shut down rainwater piping at the supply source and drain the riser.
Shut down potable piping at the meter.
Uncover and disconnect the cross‑connection.
Retest per the visual and cross‑connection procedures.
Chlorinate the potable system to 50 ppm and hold 24 hours, then flush and perform a standard bacteriological test before recharging. § 1605.3.3.

Frequency and ongoing inspection

Initial test: required before initial operation/occupancy. § 1602.5, § 1605.3.
Routine periodic cross‑connection inspection and test frequency is listed in the minimum testing table — cross‑connection inspection and test is required after initial installation and every 12 months thereafter unless the AHJ sets a different schedule. See Table 1601.5 and § 1601.5.

Required appurtenances and preparation

Systems must have valves, air/vacuum reliefs and other appurtenances to allow deactivation/drainage and the testing sequences called for in § 1605.3. § 1602.9, § 1605.3.

Decision‑relevant quick reference table

Decision / value	Required action or threshold	Code Reference
Initial test required before occupancy	Installer performs test in presence of AHJ; test must be ruled successful before final approval	§ 1602.5
Visual inspection (pre‑test)	Dual‑system visual inspection (pumps, equipment, signs, exposed piping)	§ 1605.3.1
Cross‑connection test sequence	Potable pressurized; nonpotable shut down/drained; then reverse or follow full sequence as required	§ 1605.3.2
Minimum depressurized period	Not less than 1 hour while the other system is pressurized (AHJ may require longer)	§ 1605.3.2
Periodic re‑inspection	After initial installation and every 12 months thereafter (minimum)	Table 1601.5 / § 1601.5
If cross‑connection discovered	Shut systems at sources, uncover & disconnect, retest, chlorinate potable 50 ppm / 24 hrs, flush and bacteriological test	§ 1605.3.3
Appurtenances to enable testing	Systems must provide valves, reliefs, drains, etc., to allow deactivation and drainage	§ 1602.9

Exceptions & special cases

Temporary potable connections are permitted only for the initial cross‑connection test; temporary potable makeup must be disconnected at the conclusion of the initial test. This is explicitly allowed by exception in § 1602.4 and implemented in the test sequence in § 1605.3.2.
Where shutting off water is impractical (in certain residential, institutional or industrial buildings), the AHJ may authorize alternative testing procedures different than the sequences in the chapter. (See analogous allowance in the recycled/alternate water sections.)
The AHJ may require longer depressurization/testing times than the minimum 1 hour depending on system size and complexity. § 1605.3.2.

If any required text for a related topic is not present in the documents I reviewed, I have said so plainly above; the primary controlling text for the cross‑connection test and inspection requirements (the three sections you specified) is present and cited.

Common mistakes

Assuming the installer can certify the test without the AHJ present — the initial test must be witnessed by the AHJ per § 1602.5.
Failing to fully isolate and drain the non‑pressurized system before pressurizing the other (or failing to keep it depressurized for the required minimum 1 hour) — this defeats the test. § 1605.3.2.
Forgetting to provide the necessary appurtenances (valves/drains/relief valves) so the AHJ can de‑activate/drain the system for testing (see § 1602.9).
Leaving a temporary potable connection in place after the initial test — the code requires the temporary potable hookup be removed at test conclusion. § 1605.3.2; exception in § 1602.4.
Not following the discovery procedure (source shut‑offs, uncovering, disconnecting, chlorinating potable to 50 ppm for 24 hours, then bacteriological testing) if a cross‑connection is found — required by § 1605.3.3.

Worked example — concrete scenario

Scenario: A multi‑family building installs a rainwater catchment system that will supply toilet flushing. The permit requires the initial cross‑connection test before occupancy.

Steps applied (with code grounding):

Prepare appurtenances: installer ensures isolation valves, drains and reliefs are accessible per § 1602.9.
AHJ schedules on‑site test; installer performs pre‑test visual inspection (check pumps, signage, exposed piping) with AHJ present as required by § 1605.3.1.
Test sequence: energize and pressurize the potable water system; shut down and completely drain the rainwater catchment water system. Keep the rainwater system empty for the minimum test period — AHJ specifies a duration but it must be at least 1 hour. Monitor all fixtures/outlets for unintended flows during that hour. § 1605.3.2.
If any rainwater outlet discharges during the potable‑pressurized period, that indicates a cross‑connection. If a cross‑connection is detected, immediately follow the discovery procedure: shut rainwater at supply, shut potable at meter, uncover/disconnect the cross‑connection, retest, then chlorinate potable to 50 ppm for 24 hours, flush and do a bacteriological test before recharging. § 1605.3.3.
If the test passes, AHJ signs off and final approval to occupy is issued as required by § 1602.5.
Schedule annual cross‑connection inspection and test (minimum every 12 months) as shown in Table 1601.5.

Related provisions

§ 1602.5 — Initial cross‑connection test required before building occupancy.
§ 1605.3 — Cross‑connection inspection and testing general requirements (initial and subsequent tests).
§ 1605.3.1 — Visual system inspection (pre‑test).
§ 1605.3.2 — Cross‑connection test procedure and minimum depressurization period (1 hour minimum).
§ 1605.3.3 — Discovery of cross‑connection: shutdown, disconnect, retest, chlorination and bacteriological test.
§ 1602.4 — Connections to potable water; exception allowing temporary potable hookup for initial test (must be disconnected after).
§ 1602.9 — Requirement for appurtenances to allow deactivation/drainage for cross‑connection test.
Table 1601.5 / § 1601.5 — Minimum periodic testing and inspection frequencies (cross‑connection testing: after initial installation and every 12 months).
§ 603.4.2 — General backflow assembly testing responsibilities and frequency for backflow devices (related topic: backflow assembly testing standards and certified testers).

Code references

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

CPC § 1602.5. High relevance — show source text
During an initial or subsequent_ cross-connection test, the potable and rainwater catchment water systems shall be isolated from each other and independently inspected and tested to ensure there is no crossconnection in accordance with Section 1602.5. Initial or subsequent inspections or tests shall be performed in accordance with Section 1605.3.1 through Section 1605.3.3 . 1605.3.1 Visual System Inspection. Prior to 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) Pumps, equipment, equipment room signs, and exposed piping in an equipment room shall be checked.

1605.3.2 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 rainwater catchment water system shall be shut down and completely drained.

(2) The potable water system shall remain pressurized for a minimum period of time specified by the Authority Having Jurisdiction while the rainwater catchment water system is empty. The minimum period the rainwater catchment water system is to remain depressurized shall be determined on a caseby-case basis, taking into account the size and complexity of the potable and rainwater catchment water distribution systems, but in no case shall that period be less than 1 hour.

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less than 15 pounds-force per square inch (psi) (103 kPa) residual pressure at the highest and most remote outlet served. Where the water pressure in the rainwater 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 in accordance with this code.

1603.14 Roof Drains. Primary and secondary roof drains, conductors, leaders, and gutters shall be designed and installed in accordance with this code.

1603.15 Water Quality Devices and Equipment. Devices and equipment used to treat rainwater to maintain the minimum water quality requirements determined by the Authority Having Jurisdiction shall be listed or labeled (thirdparty certified) by a listing agency (accredited conformity assessment body) and approved for the intended application.

1603.16 Freeze Protection. Tanks and piping installed in locations subject to freezing shall be provided with an approved means of freeze protection.

1603.17 Debris Removal. The rainwater catchment conveyance system shall be equipped with a debris excluder or other approved means to prevent the accumulation of leaves, needles, other debris and sediment from entering the storage tank. Devices or methods used to remove debris or sediment

shall be accessible and sized and installed in accordance with

manufacturer’s installation instructions.

1603.18 Required Filters. A filter permitting the passage of particulates not larger than 100 microns (100 µm) shall be provided for rainwater supplied to water closets, urinals, trap primers, and drip irrigation system s .

1603.19 Roof Gutters. Gutters shall maintain a minimum slope and be sized in accordance with Section 1103.3.
CPC § 1603.13 High relevance — show source text
1603.13 Pumps. Pumps serving rainwater catchment systems shall be listed. Pumps supplying water to water closets, urinals, and trap primers shall be capable of delivering not

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330 2025 CALIFORNIA PLUMBING CODE

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NONPOTABLE RAINWATER CATCHMENT SYSTEMS

CAUTION NONPOTABLE RAINWATER, DO NOT DRINK. DO NOT CONNECT TO DRINKING WATER

SYSTEM. NOTICE: CONTACT BUILDING MANAGE MENT BEFORE PERFORMING ANY WORK ON THIS

WATER SYSTEM.

This sign shall be posted in a location that is visible to anyone working on or near rainwater equipment.

1605.0 Inspection and Testing. 1605.1 General. Rainwater catchment systems shall be inspected and tested in accordance with Section 1605.2 and Section 1605.3.

1605.2 Supply System Inspection and Test. 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 a period of 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 watertightness. 1605.3 Cross-Connection Inspection and Testing. An initial visual inspection and an initial cross-connection test shall be performed on both the potable and rainwater catchment water systems before the initial operation of the rain- water catchment system. During an initial or subsequent cross-connection test, the potable and rainwater catchment water systems shall be isolated from each other and independently inspected and tested to ensure there is no crossconnection in accordance with Section 1602.5. Initial or subsequent inspections or tests shall be performed in accordance with Section 1605.3.1 through Section 1605.3.3 . 1605.3.1 Visual System Inspection. Prior to 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) Pumps, equipment, equipment room signs, and exposed piping in an equipment room shall be checked.

1605.3.2 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 rainwater catchment water system shall be shut down and completely drained.

(2) The potable water system shall remain pressurized for a minimum period of time specified by the Authority Having Jurisdiction while the rainwater catchment water system is empty. The minimum period the rainwater catchment water system is to remain depressurized shall be determined on a caseby-case basis, taking into account the size and complexity of the potable and rainwater catchment water distribution systems, but in no case shall that period be less than 1 hour.

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CPC § 1502.3.1 High relevance — show source text
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ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

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.

(2) The potable water system shall remain pressurized for a minimum period specified by the Authority Having Jurisdiction while the alternate water source system is empty. The minimum period the alternate water source system is to remain depressurized shall be determined on a case-by-case basis, taking into account the size and complexity of the potable and the alternate water source distribution systems, but in no case shall that period be less than 1 hour.

(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.
CPC § 1505.14.2.1 High relevance — show source text
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ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

dance with Section 1505.14.2.1 through Section 1505.14.2.4. The inspection and testing shall be per- formed by a cross-connection control specialist who has valid certification from a certifying organization recog- nized by the State Water Resources Control Board pur- suant to its Cross-Connection Control Policy Handbook. (1) Written reports of cross-connection inspections and testing shall be performed as provided in California Code of Regulations, Title 22, Section 60316.

(2) A cross-connection test pursuant to Section 1505.14.2.2 shall be performed on the premises of a recycled water supply system when there is material reason to believe that the potable water system or recycled water supply system separation from another water supply has been compromised. A material reason to believe that the system has been compromised may be based on, but is not limited to, evidence gathered (a) during a visual inspection performed pursuant to Section 1505.14.2.1, (b) as a result of an inspection performed following com- plaints of water quality or flow conditions consis- tent with a compromised system, or (c) during a visual inspection that indicates that the recycled water supply system has been modified. 1505.14.2.1 Visual System Inspection. A visual dual system inspection shall be conducted by the Authority Having Jurisdiction and other authorities having jurisdiction to verify that no modifications were made, and that no cross-connections are visi- ble as follows:

(1) Meter locations of the reclaimed (recycled) water source and potable water lines shall be checked.

(2) All pumps and equipment, equipment room signs, and exposed piping in equipment room shall be checked.

(3) All 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.

1505.14.2.2 Cross-Connection Test. A cross- connection test shall be performed pursuant to Sec- tion 1505.14.2. The test shall be conducted 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 recycled water supply system shall be shut down, depressurized, and drained.

(2) The potable water system shall remain pressur- ized for a minimum period of time specified by the Authority Having Jurisdiction while the recycled water supply system is empty. The min- imum period the recycled water supply system is to remain depressurized shall be determined on a case-by-case basis, taking into account the size and complexity of the potable and the recy- cled water supply systems, but in no case shall that period be less than 1 hour.

CPC § 1605.3.3 High relevance — show source text

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

(10)Where there is no flow detected in the fixtures which would indicate a cross-connection, the potable water system shall be repressurized. 1605.3.3 Discovery of Cross-Connection. In the event that a cross-connection is discovered, the following procedure, in the presence of the Authority Having Jurisdiction, shall be activated immediately:

(1) Rainwater catchment piping to the building shall be shutdown at the supply source(s), and the rainwater riser shall be drained.

(2) Potable water piping to the building shall be shutdown at the meter.

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

(4) The building shall be retested following procedures listed in Section 1605.3.1 and Section 1605.3.2.

(5) The potable water system shall be chlorinated with 50 ppm chlorine for 24 hours.

(6) 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.

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

CHAPTER 17 - REFERENCED STANDARDS

(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																X
Adopt Entire Chapter as amended (amended sections listed below)	X	X	X	X				X		X	X	X	X	X	X
Adopt only those sections that are listed below
Chapter/Section
Table 1701.

CPC § 1605.3.3 High relevance — show source text
NONPOTABLE RAINWATER CATCHMENT SYSTEMS

(3) Fixtures, potable, and rainwater shall be tested and inspected for flow. Flow from a rainwater catchment water system outlet shall indicate a cross-connection. No flow from a potable water outlet shall indicate that it is connected to the rainwater system.

(4) The drain on the rainwater catchment water system shall be checked for flow during the test and at the end of the period.

(5) The potable water system shall then be completely drained.

(6) The rainwater catchment water system shall then be activated and pressurized. When rainwater is not available for the initial cross-connection test, a tem- porary connection to a potable water supply shall be required. At the conclusion of the initial cross- connection test, the temporary connection to the potable water supply shall be disconnected.

(7) The rainwater catchment water system shall remain pressurized for a minimum period of time 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.

(8) Fixtures, potable and rainwater catchment, shall be tested and inspected for flow. Flow from a potable water system outlet shall indicate a cross-connection. No flow from a rainwater catchment water outlet shall indicate that it is connected to the potable water system.

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

(10)Where there is no flow detected in the fixtures which would indicate a cross-connection, the potable water system shall be repressurized. 1605.3.3 Discovery of Cross-Connection. In the event that a cross-connection is discovered, the following procedure, in the presence of the Authority Having Jurisdiction, shall be activated immediately:

(1) Rainwater catchment piping to the building shall be shutdown at the supply source(s), and the rainwater riser shall be drained.

(2) Potable water piping to the building shall be shutdown at the meter.

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

(4) The building shall be retested following procedures listed in Section 1605.3.1 and Section 1605.3.2.

(5) The potable water system shall be chlorinated with 50 ppm chlorine for 24 hours.

(6) 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.

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

CHAPTER 17 - REFERENCED STANDARDS

(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 § 1505.14.2.3 High relevance — show source text
(4) The drain on the recycled water supply system shall be checked for flow during the test and at the end of the test.

(5) The potable water system shall then be depres- surized and drained.

(6) The recycled water supply system shall then be activated and pressurized. For the initial cross- connection test, a temporary connection to a potable water supply shall be required to test the recycled water supply system plumbing. At the conclusion of the initial cross-connection test, the temporary connection to the potable water supply shall be disconnected.

(7) The recycled water supply system shall remain pressurized for a minimum period of time spec- ified by the Authority Having Jurisdiction while the potable water system is empty. The mini- mum 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.

(8) All fixtures, potable and reclaimed (recycled) water, shall be tested and inspected for flow. Flow from a potable water system outlet indi- cates a cross-connection. No flow from a recy- cled water supply system outlet will indicate that it is connected to the potable water system.

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

(10)Where there is no flow detected in the fixtures that would indicate a cross-connection, the potable water system shall be repressurized.

Where shutting off the water is not practical for res- idential, institutional, or industrial buildings, the Authority Having Jurisdiction may authorize testing procedures other than those described above. 1505.14.2.3 Discovery of Cross-Connection. In the event that a cross-connection is discovered, the following procedure shall be activated immedi- ately:

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

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

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

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

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ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

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

Section 1505.14.2.2.

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

(7) The potable water system shall be flushed after 24 hours, and a standard bacteriological test shall be performed. Where test results are acceptable, the potable water system shall be permitted to be recharged. 1505.14.2.4 Periodic Inspection. Periodic visual inspections of recycled water supply systems shall be required by the recycled water supplier or designee following the procedures in Section _1505.14.2.1.
CPC § 1505.14.1 High relevance — show source text
1505.14.1 Supply System Inspection and Test. Recycled water supply systems shall be inspected and tested in accordance with this code for testing of potable water piping. 1505.14.2 Cross-Connection Inspection and Test- ing. An initial visual inspection and an initial cross-con- nection test shall be performed on both the potable and recycled water supply systems before the initial opera- tion of the recycled water supply system. During an ini- tial or subsequent cross-connection test, the potable water system and recycled water supply system shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection in

accordance with Section 1505.14.2.2. Initial or subse- quent inspections or tests shall be performed in accor-

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1505.9.2 Valve and Appurtenance Access Door Signs. Each reclaimed (recycled) water valve within a wall shall have its access door into the wall equipped with a warning sign approximately 6 inches by 6 inches (152 mm x 152 mm) with wording in approximately 3/8 inch (9.5 mm) letters on a purple background. The word- ing text and format of the sign shall be substantially the same as that specified in Section 1505.13.3. The signs shall be attached inside the access door frame and shall hang in the center of the access door frame. This sign requirement shall be applicable to any and all access doors, hatches, etc., leading to reclaimed (recycled) water piping and appurtenances.

1505.10 Hose Bibbs. Hose bibbs shall not be allowed on reclaimed (recycled) water piping systems. Only quick cou- plers that differs from those installed on the potable water system shall be used on the recycled water piping system in areas subject to public access . Quick couplers supplying reclaimed (recycled) water shall be marked with the words: “CAUTION: NONPOTABLE RECYCLED WATER, DO NOT DRINK,” and one of the symbol s in Figure 1505.10.

Exception: In accordance with Health and Safety Code Sec- tion 8117 and Section 8118, hose bibbs are approved for use in cemeteries supplied with reclaimed (recycled) water. A hose bibb in an area subject to access by the general public shall be equipped with a sign marked “CAUTION: NON- POTABLE RECYCLED WATER, DO NOT DRINK,” and one of the symbols in Figure 1505.10.

FIGURE 1505.10

1505.11 Required Appurtenances. The recycled water supply system and the potable water system within the building and the premises shall be provided with the required appurtenances (e.g., valves, air/vacuum relief valves, etc.) to allow for testing as required for a cross-connection test in accordance with Section 1505.14.2 .
CPC § 1505.13.2 High relevance — show source text
1505.13.2 Tank-Type Toilet Signs. Where tank-type toilets (water closets) are flushed with recycled water, a permanent sign (such as plastic or stainless steel) shall be installed inside the tank to warn that the water within the tank is not a suitable emergency drinking water sup- ply. The sign shall be labeled: “CAUTION: NON- POTABLE RECYCLED WATER – DO NOT DRINK.”

1505.13.3 Equipment Room Signs. Each room con- taining reclaimed (recycled) water equipment shall have a sign posted in a location that is visible to anyone work- ing on or near reclaimed (recycled) water equipment with the following wording in 1 inch (25.4 mm) letters on a purple background:

“CAUTION: NONPOTABLE RECYCLED WATER, DO NOT DRINK. DO NOT CONNECT TO DRINKING

WATER SYSTEM. NOTICE: CONTACT BUILDING

MANAGEMENT BEFORE PERFORMING ANY WORK

ON THIS WATER SYSTEM.”

1505.14 Inspection and Testing. Recycled water supply systems shall be inspected and tested in accordance with Section 1505.14.1 and Section 1505.14.2. The reclaimed (recy- cled) water purveyor or other designated appointee may substitute for the Authority Having Jurisdiction for the pur- pose of inspections and tests pursuant to this section . 1505.14.1 Supply System Inspection and Test. Recycled water supply systems shall be inspected and tested in accordance with this code for testing of potable water piping. 1505.14.2 Cross-Connection Inspection and Test- ing. An initial visual inspection and an initial cross-con- nection test shall be performed on both the potable and recycled water supply systems before the initial opera- tion of the recycled water supply system. During an ini- tial or subsequent cross-connection test, the potable water system and recycled water supply system shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection in

accordance with Section 1505.14.2.2. Initial or subse- quent inspections or tests shall be performed in accor-

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1505.9.2 Valve and Appurtenance Access Door Signs. Each reclaimed (recycled) water valve within a wall shall have its access door into the wall equipped with a warning sign approximately 6 inches by 6 inches (152 mm x 152 mm) with wording in approximately 3/8 inch (9.5 mm) letters on a purple background. The word- ing text and format of the sign shall be substantially the same as that specified in Section 1505.13.3. The signs shall be attached inside the access door frame and shall hang in the center of the access door frame. This sign requirement shall be applicable to any and all access doors, hatches, etc., leading to reclaimed (recycled) water piping and appurtenances.
CPC § 105.2.6 High relevance — show source text
The equipment, material, and labor necessary for inspection or tests shall be furnished by the person to whom the permit is issued or by whom inspection is requested. 105.2.6 Reinspections. A reinspection fee shall be permitted to be assessed for each inspection or reinspection where such portion of work for which inspection is called is not complete or where required corrections have not been made.

This provision shall not be interpreted as requiring reinspection fees the first time a job is rejected for failure to be in accordance with the requirements of this code, but as controlling the practice of calling for inspections before the job is ready for inspection or reinspection.

Reinspection fees shall be permitted to be assessed where the approved plans are not readily available to the inspector, for failure to provide access on the date for which the inspection is requested, or for deviating from plans requiring the approval of the Authority Having Jurisdiction.

To obtain reinspection, the applicant shall file an application therefore in writing upon a form furnished for that purpose and pay the reinspection fee in accordance with Table 104.5.

In instances where reinspection fees have been assessed, no additional inspection of the work will be performed until the required fees have been paid. 105.3 Testing of Systems. Plumbing systems shall be tested and approved in accordance with this code or the Authority Having Jurisdiction. Tests shall be conducted in the presence of the Authority Having Jurisdiction or the Authority Having Jurisdiction’s duly appointed representative.

No test or inspection shall be required where a plumbing system, or part thereof, is set up for exhibition purposes and has no connection with a water or drainage system. In cases where it would be impractical to provide the required water or air tests, or for minor installations and repairs, the Authority Having Jurisdiction shall be permitted to make such inspection as deemed advisable in order to be assured that the work has been performed in accordance with the intent of this code. Joints and connections in the plumbing system shall be gastight and watertight for the pressures required by the test. 105.3.1 Defective Systems. An air test shall be used in testing the sanitary condition of the drainage or plumbing system of building premises where there is reason to believe that it has become defective. In buildings or premises condemned by the Authority Having Jurisdiction because of an insanitary condition of the plumbing system, or part thereof, the alterations in such system shall be in accordance with the requirements of this code. 105.3.2 Retesting. Where the Authority Having Jurisdiction finds that the work will not pass the test, necessary corrections shall be made, and the work shall be resubmitted for test or inspection. 105.3.3 Approval. Where prescribed tests and inspections indicate that the work is in accordance with this code, a certificate of approval shall be issued by the Authority Having Jurisdiction to the permittee on demand. 105.4 Connection to Service Utilities. No person shall make connections from a source of energy or fuel to a plumbing system or equipment regulated by this code and for which a permit is required until approved by the Authority Having Jurisdiction. No person shall make connection from a watersupply line nor shall connect to a sewer system regulated by this code and for which a permit is required until approved by the Authority Having Jurisdiction. The Authority Having Jurisdiction shall be permitted to authorize temporary connection of the plumbing equipment to the source of energy or fuel for the purpose of testing the equipment.

106.0 Violations and Penalties.
CPC § 602.4 High relevance — show source text
602.4 Approval by Authority. No water piping supplied by a private water supply system shall be connected to any other source of supply without the approval of the Authority Having Jurisdiction, Health Department, or other department having jurisdiction.

603.0 Cross-Connection Control.

603.1 General. Cross-connection control shall be provided in accordance with the provisions of this chapter.

No person shall install a water-operated equipment or mechanism, or use a water-treating chemical or substance, where it is found that such equipment, mechanism, chemical, or substance causes pollution or contamination of the domestic water supply. Such equipment or mechanism shall be permitted where equipped with an approved backflow prevention device or assembly.

603.2 Approval of Devices or Assemblies. Before a device or an assembly is installed for the prevention of backflow, it shall have first been approved by the Authority Having Jurisdiction. Devices or assemblies shall be tested in accordance with recognized standards or other standards acceptable to the Authority Having Jurisdiction. Backflow prevention devices and assemblies shall comply with Table 603.2, except for specific applications and provisions as stated in Section 603.5.1 through Section 603.5.22.

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WATER SUPPLY AND DISTRIBUTION

Devices or assemblies installed in a potable water supply system for protection against backflow shall be maintained in good working condition by the person or persons having control of such devices or assemblies. Such devices or assemblies shall be tested at the time of installation, repair, or relocation and not less than on an annual schedule thereafter, or more often where required by the Authority Having Jurisdiction. Where found to be defective or inoperative, the device or assembly shall be repaired or replaced. No device or assembly shall be removed from use or relocated or other device or assembly substituted, without the approval of the Authority Having Jurisdiction.

Testing or maintenance shall be performed by a certified backflow assembly tester or repairer certified in accordance with ASSE/IAPMO/ANSI Series 5000 or any other additional certification approved by the Authority Having Jurisdiction.

603.3 Backflow Prevention Devices, Assemblies, and Methods. Backflow prevention devices, assemblies, and methods shall comply with Section 603.3.1 through Section 603.3.12.

603.3.1 Air Gap. The minimum air gap to afford backflow protection shall be in accordance with Table 603.3.1. 603.3.2 Atmospheric Vacuum Breaker (AVB). An atmospheric vacuum breaker consists of a body, a checking member, and an atmospheric port.

603.3.3 Hose Connection Backflow Preventer. A hose connection backflow preventer consists of two independent check valves with an independent atmospheric vent between and a means of field testing and draining.

603.3.4 Double Check Valve Backflow Prevention Assembly (DC). A double check valve backflow prevention assembly consists of two independently acting internally loaded check valves, four properly located test cocks, and two isolation valves.

603.3.5 Pressure Vacuum Breaker Backflow Pre- vention Assembly (PVB). A pressure vacuum breaker backflow prevention assembly consists of a loaded air inlet valve, an internally loaded check valve, two properly located test cocks, and two isolation valves.
CPC § 101.12.2 High relevance — show source text
S 101.12.2 Bypass Connection. A bypass shall be provided for the input connection to the stormwater treatment system. The bypass shall be a diverter valve normally open to the stormwater treatment system. The normally closed port of the diverter valve shall be connected directly to the storm drainage system or combined sewer system in accordance with this code.

TABLE S 101.11(1)

RISK LEVELS
- See Section S 101.2 for other uses approved by the Authority Having Jurisdiction.
S 101.12.3 Overflow Connection. Stormwater treatment overflow shall be connected directly to the storm drainage or combined sewer system in accordance with this code. The overflow shall be provided with a backwater valve at the point of connection to the storm drainage or combined sewer system. The backwater valve shall be accessible for inspection and maintenance.

S 101.12.4 Fail-Safe Mechanisms. Stormwater treatment systems shall be equipped with an automatic shutdown device of the treatment process in the event of a malfunction.

S 101.12.5 Flow Meter Totalizer. Buildings with stormwater treatment systems shall include a flow meter totalizer on the treated stormwater distribution system and a flow meter totalizer on the potable make-up water pipeline to the stormwater treatment system. S 101.12.6 Cross-Connection Inspection and Testing. A cross-connection test is required in accordance with Section 1502.0. 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. The test shall be ruled successful by the Authority Having Jurisdiction before final approval is granted. S 101.13 Commissioning. Onsite stormwater treatment systems shall be commissioned in accordance with the requirements of Section S 101.13.1 through Section S 101.13.4.

S 101.13.1 Commissioning Requirements. Commissioning for stormwater treatment systems shall be included in the design and construction processes of the project. Commissioning shall be performed by a person who demonstrates competency in commissioning stormwater treatment systems as required by the Authority Having Jurisdiction. S 101.13.2 Commissioning Plan. The construction documents shall include the commissioning plan for the stormwater treatment system. The commissioning plan shall be approved by the Authority Having Jurisdiction prior to commissioning the stormwater treatment system. The commissioning plan shall include the following:

(1) General project information.

(2) Equipment to be tested, including the test methodology.

(3) Processes to be tested.

(4) Criteria or process for testing.

(5) Criteria or process for acceptance.

(6) Commissioning team contact information.

(7) Commissioning process activities, schedules, and responsibilities.

(8) Plans for the completion of functional performance testing, post construction documentation and training, and the commissioning report. S 101.13.3 Performance Testing. Performance tests shall verify that the installation and operation of the

TABLE S 101.11(2)

MONITORING PARAMETERS

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APPENDIX S
CPC § 1603.4 High relevance — show source text
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| |

Cross-connection inspection
and test.*|After initial installation and
every 12 months thereafter| |

Test water quality of rainwater
catchment systems required by
Section 1603.4 to maintain a
minimum water quality.|Every 12 months. After system
renovation or repair.|
- The cross-connection test shall be performed in the presence of the Authority Having Jurisdiction in accordance with the requirements of this chapter.
1601.5.1 Maintenance Responsibility. The required maintenance and inspection of rainwater catchment systems shall be the responsibility of the property owner unless otherwise required by the Authority Having Jurisdiction.

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NONPOTABLE RAINWATER CATCHMENT SYSTEMS

1601.6 Operation and Maintenance Manual. An operation and maintenance manual for rainwater catchment systems required to have a permit in accordance with Section 1601.3, shall be supplied to the building owner by the system designer or installer . The operating and maintenance manual shall include the following:

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

(2) Instructions for operating and maintaining the system.

(3) Instructions on maintaining the required water quality as for rainwater catchment systems .

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

(5) Applicable testing, inspection, and maintenance frequencies in accordance with Section 1601.5.

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

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

1601.7 Minimum Water Quality Requirements. The minimum water quality for rainwater catchment systems shall comply with the applicable water quality requirements for the intended application as determined by the Authority Having Jurisdiction. Water quality for nonpotable rainwater catchment systems shall comply with Section 1603.4. In the absence of water quality requirements for harvested rainwa- ter, Table 1603.4 shall apply.

Exceptions:

(1) Water treatment is not required for rainwater catchment systems used for aboveground irrigation with a maximum storage capacity of 360 gallons (1363 L).

(2) Water treatment is not required for rainwater catchment systems used for surface, subsurface or drip irrigation. 1601.8 Material Compatibility. Rainwater catchment systems shall be constructed of materials that are compatible with the type of pipe and fitting materials, water treatment, and water conditions in the system. 1601.9 System Controls. Controls for pumps, valves, and other devices that contain mercury that come in contact with rainwater supply shall not be permitted. 1601.10 Separation Requirements. Underground rainwater catchment service piping shall be separated from the building sewer in accordance with Section 609.2.
CPC § 1602.2 High relevance — show source text
** 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. 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. 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
CPC § 1603.19 High relevance — show source text
1603.19 Roof Gutters. Gutters shall maintain a minimum slope and be sized in accordance with Section 1103.3.

1603.20 Rainwater Diversion Valves. Rainwater diversion valves ranging from 2 inches (50 mm) through 12 inches (300 mm) in diameter shall be an approved diverter valve . Valves shall be readily accessible and include a filter located upstream of the valve when required.

1604.0 Signs. 1604.1 General. Signs in buildings using rainwater shall be in accordance with Section 1604.2 and Section 1604.3 , and applicable requirements of the California Building Code .

1604.2 Commercial, Industrial, Institutional and Res- idential Restroom Signs. A sign shall be installed in restrooms in commercial, industrial, and institutional occupancies , and in residential common use areas using nonpotable rainwater for water closets, urinals, or both. Signs shall comply with all applicable requirements of the Califor- nia Building Code. Each sign shall contain the following text:

TO CONSERVE WATER, THIS BUILDING USES RAINWATER TO FLUSH TOILETS AND URINALS.

1604.3 Equipment Room Signs. Each equipment room containing nonpotable rainwater equipment shall have a sign posted with the following wording in 1 inch (25.4 mm) let ters:

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NONPOTABLE RAINWATER CATCHMENT SYSTEMS

(3) Fixtures, potable, and rainwater shall be tested and inspected for flow. Flow from a rainwater catchment water system outlet shall indicate a cross-connection. No flow from a potable water outlet shall indicate that it is connected to the rainwater system.

(4) The drain on the rainwater catchment water system shall be checked for flow during the test and at the end of the period.

(5) The potable water system shall then be completely drained.

(6) The rainwater catchment water system shall then be activated and pressurized. When rainwater is not available for the initial cross-connection test, a tem- porary connection to a potable water supply shall be required. At the conclusion of the initial cross- connection test, the temporary connection to the potable water supply shall be disconnected.

(7) The rainwater catchment water system shall remain pressurized for a minimum period of time 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.

(8) Fixtures, potable and rainwater catchment, shall be tested and inspected for flow. Flow from a potable water system outlet shall indicate a cross-connection. No flow from a rainwater catchment water outlet shall indicate that it is connected to the potable water system.

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

CPC § 1601.5 High relevance — show source text

TABLE 1601.5 MINIMUM ALTERNATE WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY

DESCRIPTION	MINIMUM FREQUENCY
Inspect and clean filters and screens, and replace (where necessary).	Every 3 months
Inspect and verify that disinfection, filters, and water quality treatment devices and systems are operational and maintaining minimum water quality requirements as determined by the Authority Having Jurisdiction.	In accordance with manufac- turer’s instructions and the Authority Having Jurisdiction.
Inspect and clear debris from rainwater gutters, downspouts, and roof washers.	Every 6 months
Inspect and clear debris from the roof or another above- ground rainwater collection surfaces.	Every 6 months
Remove tree branches and vegetation overhanging a roof or other aboveground rainwater collection surfaces.	As needed
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
Cross-connection inspection and test.*	After initial installation and every 12 months thereafter
Test water quality of rainwater catchment systems required by Section 1603.4 to maintain a minimum water quality.	Every 12 months. After system renovation or repair.

The cross-connection test shall be performed in the presence of the Authority Having Jurisdiction in accordance with the requirements of this chapter.

1601.5.1 Maintenance Responsibility. The required maintenance and inspection of rainwater catchment systems shall be the responsibility of the property owner unless otherwise required by the Authority Having Jurisdiction.

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NONPOTABLE RAINWATER CATCHMENT SYSTEMS

1601.6 Operation and Maintenance Manual. An operation and maintenance manual for rainwater catchment systems required to have a permit in accordance with Section 1601.3, shall be supplied to the building owner by the system designer or installer . The operating and maintenance manual shall include the following:

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

(2) Instructions for operating and maintaining the system.

(3) Instructions on maintaining the required water quality as for rainwater catchment systems .

Frequently asked questions

Who must perform and witness the initial cross‑connection test?

The installer performs the test, but the test must be performed in the presence of the Authority Having Jurisdiction (AHJ) and be ruled successful by the AHJ before final approval. § 1602.5, § 1605.3.2.

How long must the non‑pressurized system remain empty during the test?

The AHJ sets the period case‑by‑case, but in no case shall it be less than 1 hour. § 1605.3.2.

Can I temporarily connect potable water to the rainwater system to do the test?

Yes — a temporary potable connection is permitted for the initial cross‑connection test only; it must be disconnected at the conclusion of that test. See the exception in § 1602.4 and the procedures in § 1605.3.2.

What happens if a cross‑connection is found?

Follow the discovery procedure: shut off rainwater supply(s) and potable at the meter, uncover and disconnect the cross‑connection, retest, chlorinate potable water to 50 ppm for 24 hours, flush, and obtain a satisfactory bacteriological test before recharging. § 1605.3.3.

How often must cross‑connection testing/inspection occur after initial approval?

Minimum requirement is after initial installation and every 12 months thereafter (unless the AHJ sets a different schedule). See Table 1601.5 / § 1601.5.

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