CRC · California Residential Code
Building sewer connections, private sewage & prohibited discharges
If your house has plumbing, you must connect it to a public sewer or, if no public sewer is available, to an approved private sewage disposal system; you cannot route rain or groundwater into the sanitary sewer without AHJ approval, and the AHJ or Health Officer can require a watertight holding tank when needed to protect health or the sewer system (see **§ 713.0**, **§ 713.2**, **§ 714.2**, **§ 714.5**).
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
Buildings with plumbing fixtures must be connected to a public or an approved private sewage disposal system; where a public sewer is not available the drainage must connect to an approved private system (§ 713.0). Rain, surface, or subsurface water must not be connected to or discharged into the sanitary drainage system unless the Authority Having Jurisdiction approves the connection (§ 714.2). An approved, watertight holding tank must be installed where required by the Authority or Health Officer to prevent contamination or damage to the public sewer or other hazards (§ 714.5).
The single most important rule: if a public sewer is not available, you must connect to an approved private sewage disposal system; and never send rain or groundwater into the sanitary sewer without AHJ approval.
Requirements in detail
Scope and trigger: when a sewer connection is required
- A building that has plumbing fixtures or premises with drainage piping shall be connected to either a public sewer or an approved private sewage disposal system (§ 713.0).
- Where no public sewer intended to serve a lot is available in an abutting street/right-of-way, drainage piping shall connect to an approved private sewage disposal system; design and approval are under the Authority Having Jurisdiction (see Appendix H referenced by § 713.2). (§ 713.2)
What you cannot discharge into sanitary drainage
- Rain, surface, or subsurface water: prohibited from being connected to or discharged into a drainage system unless approved by the Authority Having Jurisdiction (§ 714.2).
- The code also makes it unlawful to deposit solids, ashes, rags, flammable/poisonous/explosive liquids or gases, oils, grease, or other things that could damage the public or private sewer (see § 714.1 and related unlawful practices).
Holding tanks (watertight tanks)
- Where required by the Authority Having Jurisdiction or the Health Officer to prevent contamination, damage to the public sewer, or other hazardous/nuisance conditions, an approved watertight sewage/wastewater holding tank must be installed; contents are periodically removed and disposed of off‑site (§ 714.5).
Design & approval responsibilities
- The Authority Having Jurisdiction is the approving authority for private systems, any exceptions, and for approving discharges of rain/surface/subsurface water to the drainage system (§ 713.2 and § 714.2).
- Appendix H provides the design guidelines for private sewage disposal systems (type of system, when septic tank + subsurface disposal field or seepage pits are required, siting relative to groundwater and flood hazards). See Appendix H referenced by § 713.2.
Quick decision table
| Decision factor | What the code requires | Code Reference |
|---|---|---|
| Building has plumbing fixtures | Must connect to a public sewer or an approved private sewage disposal system | § 713.0 |
| No public sewer available at lot | Connect to an approved private sewage disposal system; follow AHJ and Appendix H guidance | § 713.2 |
| Connecting rain/surface/subsurface water to sanitary drains | Not allowed unless approved by the Authority Having Jurisdiction | § 714.2 |
| When a holding tank is required | Install an approved watertight holding tank when AHJ/Health Officer finds it necessary to prevent contamination, damage, nuisance | § 714.5 |
| Private system siting/design (soil/groundwater) | Follow Appendix H design rules (septic tank + subsurface field, seepage pits, setbacks, groundwater limits) | Appendix H (referenced by § 713.2) |
Exceptions & special cases
- Local AHJ discretion: the Authority Having Jurisdiction may approve private systems, grant exceptions, or require additional measures where needed for health/safety (§ 713.2; Appendix H).
- Holding tank installations are conditional: tanks are only required where the AHJ or Health Officer finds they are necessary to prevent contamination, damage, or nuisance (§ 714.5).
- Appendix H contains site‑specific thresholds (for example, when groundwater is close to the surface) that affect whether a septic tank + disposal field, seepage pits, or other system is required; those Appendix H limits (e.g., groundwater within 12 feet) are mandatory where Appendix H is adopted by the AHJ.
Common mistakes
- Assuming you may route roof drains or stormwater into the sanitary building sewer — this is prohibited unless the AHJ expressly approves (§ 714.2).
- Installing a private sewage disposal system without verifying whether a public sewer is actually available or without AHJ approval — the code requires AHJ approval where private disposal is used (§ 713.2).
- Relying on “do‑it‑yourself” holding tanks without meeting the AHJ/Health Officer’s requirement for an approved watertight tank and an off‑site disposal plan (§ 714.5).
- Overlooking Appendix H siting rules (soil porosity, groundwater, flood hazard) when designing a private system — failure here leads to systems that don’t absorb effluent properly (Appendix H referenced by § 713.2).
Worked example — concrete scenario
Scenario: A homeowner will build a 3-bedroom single-family dwelling on a rural lot. There is no public sewer in the street immediately in front of the lot. The groundwater on site is measured at 9 feet below grade.
Applying the code:
- Because the dwelling will have plumbing fixtures and no public sewer is available to serve the lot, the drain piping must connect to an approved private sewage disposal system as approved by the AHJ (§ 713.2).
- Appendix H (referenced by § 713.2) requires a septic tank and subsurface disposal field where groundwater is within 12 feet of the surface; with groundwater at 9 ft the AHJ will require a septic tank + disposal field (or an approved alternative) and will evaluate soil porosity and expansion area per Appendix H.
- If the AHJ determines that the site conditions or public‑health risk make draining to the sewer (if it existed) or a conventional disposal field unacceptable, the AHJ or Health Officer could instead require an approved watertight holding tank with off‑site disposal plan (§ 714.5).
- The homeowner must not connect roof leaders or stormwater to the septic disposal field or sanitary system unless the AHJ approves such a connection (§ 714.2).
Related provisions
- § 713.1 — Where required: restates that buildings with plumbing fixtures must be connected to public or private sewer.
- § 713.4 — Public sewer availability (distance/availability rules used by AHJ).
- § 713.5 — Permits: no permit for private sewage disposal when a public sewer is available (see code for AHJ enforcement).
- § 714.1 — Unlawful practices (prohibited deposits that damage sewers).
- Appendix H (H 101.x) — Private sewage disposal systems: design, siting, groundwater limits, required expansion area and flood hazard rules (referenced by § 713.2).
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 713.6 High relevance — show source text
713.6 Lot. On every lot or premises hereafter connected to a public sewer, plumbing, and drainage systems or parts thereof on such lot or premises shall be connected with such public sewer.
713.7 Installation. In cities, counties, or both where the installation of building sewers is under the jurisdiction of a department other than the Authority Having Jurisdiction, the provisions of this code relating to building sewers need not apply.
Exception: Single-family dwellings and buildings or structures accessory thereto, existing and connected to an approved private sewage disposal system prior to the time of connecting the premises to the public sewer shall be permitted, where no hazard, nuisance, or insanitary condition is evidenced, and written permission has been obtained from the Authority Having Jurisdiction, remain connected to such properly maintained private sewage disposal system where there is insufficient grade or fall to permit drainage to the sewer by gravity.
714.0 Damage to Public Sewer or Private Sewage Disposal System.
714.1 Unlawful Practices. It shall be unlawful for a person to deposit, by means whatsoever, into a plumbing fixture, floor drain, interceptor, sump, receptor, or device which is
2025 CALIFORNIA PLUMBING CODE 175
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SANITARY DRAINAGE
connected to a drainage system, public sewer, private sewer, septic tank, or cesspool, ashes; cinders; solids; rags; flammable, poisonous, or explosive liquids or gases; oils; grease; and whatsoever that is capable of causing damage to the public sewer, private sewer, or private sewage disposal system.
714.2 Prohibited Water Discharge. No rain, surface, or subsurface water shall be connected to or discharged into a drainage system unless first approved by the Authority Having Jurisdiction.
714.3 Prohibited Sewer Connection. No cesspool, septic tank, seepage pit, or drain field shall be connected to a public sewer or to a building sewer leading to such public
sewer.
714.4 Commercial Food Waste Disposer. The Authority Having Jurisdiction shall review before approval, the installation of a commercial food waste disposer connecting to a private sewage disposal system.
714.5 Tanks. An approved type, watertight sewage or wastewater holding tank, the contents of which, due to their character, shall be periodically removed and disposed of at some approved off-site location, shall be installed where required by the Authority Having Jurisdiction or the Health Officer to prevent anticipated surface or subsurface contamination or pollution, damage to the public sewer, or other hazardous or nuisance conditions.
715.0 Building Sewer Materials.
715.1 Materials. The building sewer, beginning 2 feet (610 mm) from a building or structure, shall be of such materials as prescribed in this code.
715.2 Joining Methods and Materials. Joining methods and materials shall be as prescribed in this code.
715.3 Existing Sewers. Where permitted by the Authority Having Jurisdiction, trenchless methods of rehabilitation of existing building sewer and building storm sewers shall be installed in accordance with Section 715.3.1 or Section 715.3.2.
CRC § 712.0 High relevance — show source text
712.0 Testing . . . . . . . . . . . . . . . . . . . . .175
712.1 Media . . . . . . . . . . . . . . . . . . . . . .175
712.2 Water Test . . . . . . . . . . . . . . . . . .175
712.3 Air Test . . . . . . . . . . . . . . . . . . . . .175
PART II Building Sewers . . . . . . . . . . . . .175
713.0 Sewer Required . . . . . . . . . . . . . .175
713.1 Where Required . . . . . . . . . . . . . .175
713.2 Private Sewage Disposal System . . . . . . . . . . . . . . . . . . . . .175
713.3 Public Sewer . . . . . . . . . . . . . . . . .175
713.4 Public Sewer Availability . . . . . . .175
713.5 Permit . . . . . . . . . . . . . . . . . . . . . .175
713.6 Lot . . . . . . . . . . . . . . . . . . . . . . . . .175
713.7 Installation . . . . . . . . . . . . . . . . . .175
714.0 Damage to Public Sewer or Private Sewage Disposal System . . . . . . . . . . . . . . . . . . . . .175
714.1 Unlawful Practices . . . . . . . . . . . .175
714.2 Prohibited Water Discharge . . . . .176
714.3 Prohibited Sewer Connection . . . .176
714.4 Commercial Food Waste
Disposer . . . . . . . . . . . . . . . . . . . .176
714.5 Tanks . . . . . . . . . . . . . . . . . . . . . .176
715.0 Building Sewer Materials . . . . . . .176
715.1 Materials . . . . . . . . . . . . . . . . . . . .176
715.2 Joining Methods and Materials . . .176
715.3 Existing Sewers . . . . . . . . . . . . . .176
716.0 Markings . . . . . . . . . . . . . . . . . . . .176
716.1 General . . . . . . . . . . . . . . . . . . . . .176
717.0 Size of Building Sewers . . . . . . . .176
717.1 General . . . . . . . . . . . . . . . . . . . . .176
Table 717.1 Maximum/Minimum Fixture
Unit Loading on Building Sewer Piping . . . . . . . . . . . . . . . .176
717.2 Meat and Poultry Processing Plants . . . . . . . . . . . . . . . . . . . . . .176
718.0 Grade, Support, and Protection of Building Sewers . . .176
718.1 Slope . . . . . . . . . . . . . . . . . . . . . .176
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CRC § 713.0 High relevance — show source text
Part II – Building Sewers.
713.0 Sewer Required. 713.1 Where Required. A building in which plumbing fixtures are installed and premises having drainage piping thereon shall have a connection to a public or private sewer, except as provided in Section 713.2, and Section 713.4. 713.2 Private Sewage Disposal System. Where no public sewer intended to serve a lot or premises is available in a thoroughfare or right of way abutting such lot or premises, drainage piping from a building or works shall be connected to a private sewage disposal system as approved by the Authority Having Jurisdiction. See Appendix H. 713.3 Public Sewer. Within the limits prescribed by Section 713.4 hereof, the rearrangement or subdivision into smaller parcels of a lot that abuts and is served by a public sewer shall not be deemed cause to permit the construction of a private sewage disposal system, and plumbing or drainage systems on a smaller parcel or parcels shall connect to the public sewer. 713.4 Public Sewer Availability. The public sewer shall be permitted to be considered as not being available where such public sewer or a building or an exterior drainage facility connected thereto is located more than 200 feet (60 960 mm) from a proposed building or exterior drainage facility on a lot or premises that abut and is served by such public sewer.
[HCD 1] For residential occupancies, the public sewer may be considered as not being available by the Authority Having Jurisdiction.
713.5 Permit. No permit shall be issued for the installation, alteration, or repair of a private sewage disposal system, or part thereof, on a lot for which a connection with a public sewer is available.
713.6 Lot. On every lot or premises hereafter connected to a public sewer, plumbing, and drainage systems or parts thereof on such lot or premises shall be connected with such public sewer.
713.7 Installation. In cities, counties, or both where the installation of building sewers is under the jurisdiction of a department other than the Authority Having Jurisdiction, the provisions of this code relating to building sewers need not apply.
Exception: Single-family dwellings and buildings or structures accessory thereto, existing and connected to an approved private sewage disposal system prior to the time of connecting the premises to the public sewer shall be permitted, where no hazard, nuisance, or insanitary condition is evidenced, and written permission has been obtained from the Authority Having Jurisdiction, remain connected to such properly maintained private sewage disposal system where there is insufficient grade or fall to permit drainage to the sewer by gravity.
714.0 Damage to Public Sewer or Private Sewage Disposal System.
714.1 Unlawful Practices. It shall be unlawful for a person to deposit, by means whatsoever, into a plumbing fixture, floor drain, interceptor, sump, receptor, or device which is
2025 CALIFORNIA PLUMBING CODE 175
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
SANITARY DRAINAGE
connected to a drainage system, public sewer, private sewer, septic tank, or cesspool, ashes; cinders; solids; rags; flammable, poisonous, or explosive liquids or gases; oils; grease; and whatsoever that is capable of causing damage to the public sewer, private sewer, or private sewage disposal system.
CRC § 714.2 High relevance — show source text
714.2 Prohibited Water Discharge. No rain, surface, or subsurface water shall be connected to or discharged into a drainage system unless first approved by the Authority Having Jurisdiction.
714.3 Prohibited Sewer Connection. No cesspool, septic tank, seepage pit, or drain field shall be connected to a public sewer or to a building sewer leading to such public
sewer.
714.4 Commercial Food Waste Disposer. The Authority Having Jurisdiction shall review before approval, the installation of a commercial food waste disposer connecting to a private sewage disposal system.
714.5 Tanks. An approved type, watertight sewage or wastewater holding tank, the contents of which, due to their character, shall be periodically removed and disposed of at some approved off-site location, shall be installed where required by the Authority Having Jurisdiction or the Health Officer to prevent anticipated surface or subsurface contamination or pollution, damage to the public sewer, or other hazardous or nuisance conditions.
715.0 Building Sewer Materials.
715.1 Materials. The building sewer, beginning 2 feet (610 mm) from a building or structure, shall be of such materials as prescribed in this code.
715.2 Joining Methods and Materials. Joining methods and materials shall be as prescribed in this code.
715.3 Existing Sewers. Where permitted by the Authority Having Jurisdiction, trenchless methods of rehabilitation of existing building sewer and building storm sewers shall be installed in accordance with Section 715.3.1 or Section 715.3.2.
715.3.1 Sewer Pipe Lining. For trenchless installation of resin-impregnated flexible tubing to line existing building sewers and building storm sewers installation shall be in accordance with ASTM F1216, ASTM F2561, ASTM F2599, or ASTM F3240.
715.3.2 Sewer Pipe Replacement. For trenchless installation of polyethylene (PE) pipe using the pipe bursting method to replace existing building sewers and building storm sewers materials shall be in accordance with ASTM F714.
716.0 Markings.
716.1 General. Pipe, brick, block, prefabricated septic tanks, prefabricated septic tank or seepage pit covers, or other parts or appurtenances incidental to the installation of building sewers or private sewage disposal systems shall be in accordance with the approval requirements of Chapter 3 of this code.
717.0 Size of Building Sewers. 717.1 General. The minimum size of a building sewer shall be determined on the basis of the total number of fixture units drained by such sewer, in accordance with Table 717.1. No building sewer shall be smaller than the building drain.
For alternate methods of sizing building sewers, see Appendix C.
TABLE 717.1
MAXIMUM/MINIMUM FIXTURE UNIT LOADING
CRC § 306.0 High relevance — show source text
306.0 Industrial Wastes.
306.1 Detrimental Wastes. Wastes detrimental to the public sewer system or detrimental to the functioning of the sewage treatment plant shall be treated and disposed of as found necessary and directed by the Authority Having Jurisdiction. 306.2 Safe Discharge. Sewage or other waste from a plumbing system that is capable of being deleterious to surface or subsurface waters shall not be discharged into the ground or a waterway unless it has first been rendered safe by some acceptable form of treatment in accordance with the Authority Having Jurisdiction.
307.0 Location.
307.1 System. Except as otherwise provided in this code, no plumbing system, drainage system, building sewer, private sewage disposal system, or parts thereof shall be located in a lot other than the lot that is the site of the building, structure, or premises served by such facilities.
307.2 Ownership. No subdivision, sale, or transfer of ownership of existing property shall be made in such manner that the area, clearance, and access requirements of this code are decreased.
308.0 Prohibited Locations.
308.1 General. Piping, fixtures, appliances, or equipment shall not be so located as to interfere with the normal use thereof or with the normal operation and use of windows, doors, or other required facilities.
309.0 Workmanship.
309.1 Engineering Practices. Design, construction, and workmanship shall be in accordance with accepted engineering practices and shall be of such character as to secure the results sought to be obtained by this code. 309.2 Concealing Imperfections. It is unlawful to conceal cracks, holes, or other imperfections in materials by welding, brazing, or soldering or by using therein or thereon paint, wax, tar, solvent cement, or other leak-sealing or repair agent.
309.3 Burred Ends. Burred ends of pipe and tubing shall be reamed to the full bore of the pipe or tube, and chips shall be removed.
309.4 Installation Practices. Plumbing systems shall be installed in a workmanlike manner which is in accordance with this code, applicable standards, and the manufacturer’s installation instructions. All materials shall be installed so as not to adversely affect the systems and equipment or the structure of the building, and in compliance with all laws and other provisions of this code. All plumbing systems shall be in accordance with construction documents approved by the Authority Having Jurisdiction. 309.5 Sound Transmission. Plumbing piping systems shall be designed and installed in conformance with sound limitations as required in the California Building Code .
309.6 Dead Legs. Dead legs shall have a method of flushing.
310.0 Prohibited Fittings and Practices.
310.1 Fittings. No double hub fitting, single or double tee branch, single or double tapped tee branch, side inlet quarter bend, running thread, band, or saddle shall be used as a drainage fitting.
310.2 Drainage and Vent Piping. No drainage or vent piping shall be drilled and tapped for the purpose of making connections thereto, and no cast-iron soil pipe shall be threaded.
310.3 Waste Connection. No waste connection shall be
made to a closet bend or stub of a water closet or similar fix ture.
CRC § 1.11.0. Medium relevance — show source text
This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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APPENDIX H
PRIVATE SEWAGE DISPOSAL SYSTEMS
The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.
H 101.0 General.
H 101.1 Applicability. This appendix provides general guidelines for the materials, design, and installation of private sewage disposal systems. H 101.2 General Requirements. Where permitted by Section 713.0, the building sewer shall be permitted to be connected to a private sewage disposal system in accordance with the provisions of this appendix. The type of system shall be determined on the basis of location, soil porosity, and groundwater level, and shall be designed to receive all sewage from the property. The system, except as otherwise approved, shall consist of a septic tank with effluent discharging into a subsurface disposal field, into one or more seepage pits, or into a combination of subsurface dis posal field and seepage pits. The Authority Having Jurisdiction shall be permitted to grant exceptions to the provisions of this appendix for permitted structures that have been destroyed due to fire or natural disaster, and that cannot be reconstructed in compliance with these provisions provided that such exceptions are the mini mum necessary. H 101.3 Quantity and Quality. Where the quantity or quality of the sewage is such that the above system cannot be expected to function satisfactorily for commercial, agricultural, and industrial plumbing systems; for installations where appreciable amounts of industrial or indigestible wastes are produced; for occupancies producing abnormal quantities of sewage or liquid waste; or where grease interceptors are required by other parts of this code, the method of sewage treatment and disposal shall be first approved by the Authority Having Jurisdiction. Special sewage disposal systems for minor, limited, or temporary uses shall be first approved by the Authority Having Jurisdiction. H 101.4 Septic Tank and Disposal Field Systems. Disposal systems shall be designed to utilize the most porous or absorptive portions of the soil formation. Where the groundwater level extends to within 12 feet (3658 mm) or less of the ground surface or where the upper soil is porous, and the underlying stratum is rock or impervious soil, a septic tank and disposal field system shall be installed. H 101.5 Flood Hazard Areas. Disposal systems shall be located outside of flood hazard areas.
Exception: Where suitable sites outside of flood hazard areas are not available, disposal systems shall be permitted to be located in flood hazard areas on sites where the effects of inundation under conditions of the design flood are minimized.
CRC § 304.0 Medium relevance — show source text
Exception: [HCD 1] Limited-density owner-built rural dwellings. A water closet shall not be required when an alter- nate system is provided and has been approved by the local health official. Where an alternative to the water closet is installed, a system for the disposal or treatment of graywater shall be provided to the dwelling. Graywater systems shall be designed according to water availability, use and discharge. The design, use and maintenance standards of such systems shall be the prerogative of the local health official.
304.0 Connections to Plumbing System Required. 304.1 General. Plumbing fixtures, drains, appurtenances, and appliances, used to receive or discharge liquid wastes or sewage, shall be connected properly to the drainage system of the building or premises, in accordance with the requirements of this code.
Exception: [HCD 1] Limited-density owner-built rural dwellings. Where conventional plumbing, in all or in part, is
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GENERAL REGULATIONS
installed within the structure, it shall be installed in accordance with the provisions of this code. Alternative materials and methods shall be permitted provided that the design complies with the intent of the code, and that such alternatives shall per- form to protect health and safety for the intended purpose.
305.0 Damage to Drainage System or Public Sewer.
305.1 Unlawful Practices. It shall be unlawful for a person to deposit, by any means whatsoever, into a plumbing fixture, floor drain, interceptor, sump, receptor, or device, which is connected to a drainage system, public sewer, private sewer, septic tank, or cesspool, any ashes; cinders; solids; rags; inflammable, poisonous, or explosive liquids or gases; oils; grease; or any other thing whatsoever that is capable of causing damage to the drainage system or public sewer.
306.0 Industrial Wastes.
306.1 Detrimental Wastes. Wastes detrimental to the public sewer system or detrimental to the functioning of the sewage treatment plant shall be treated and disposed of as found necessary and directed by the Authority Having Jurisdiction. 306.2 Safe Discharge. Sewage or other waste from a plumbing system that is capable of being deleterious to surface or subsurface waters shall not be discharged into the ground or a waterway unless it has first been rendered safe by some acceptable form of treatment in accordance with the Authority Having Jurisdiction.
307.0 Location.
307.1 System. Except as otherwise provided in this code, no plumbing system, drainage system, building sewer, private sewage disposal system, or parts thereof shall be located in a lot other than the lot that is the site of the building, structure, or premises served by such facilities.
307.2 Ownership. No subdivision, sale, or transfer of ownership of existing property shall be made in such manner that the area, clearance, and access requirements of this code are decreased.
308.0 Prohibited Locations.
308.1 General. Piping, fixtures, appliances, or equipment shall not be so located as to interfere with the normal use thereof or with the normal operation and use of windows, doors, or other required facilities.
309.0 Workmanship.
CRC § 8-903.3 Medium relevance — show source text
8-903.3 Materials. New nonhistorical materials shall comply with the regular code requirements. The enforcing agency shall accept alternative materials which do not create a safety hazard where their use is necessary to maintain the historical integrity of the building.
8-903.4 Drainage and vent systems. Plumbing fixtures shall be connected to an adequate drainage and vent system. The enforcing agency may require operational tests for drainage and vent systems which do not comply with applicable requirements of the regular code. Vent terminations may be installed in any location which, in the opinion of the enforcing agency, does not create a safety hazard.
8-903.5 Indirect and special wastes. Indirect and special waste systems shall be installed so that no safety hazard is created. Chemical or industrial liquid wastes which may detrimentally affect the sanitary sewer system shall be pretreated to render them safe prior to discharge.
8-903.6 Traps and interceptors. Traps and interceptors shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard. Properly maintained “S” and drum traps may remain in use.
8-903.7 Joints and connections.
8-903.7.1 Joints and connections in new plumbing systems shall comply with applicable requirements of the regular code.
8-903.7.2 Joints and connections in existing or restored systems may be of any type that does not create a safety hazard.
8-903.8 Water distribution. Plumbing fixtures shall be connected to an adequate water distribution system. The enforcing agency may require operational tests for water distribution systems which do not comply with applicable requirements of the regular code. Prohibited (unlawful) connections and cross connections shall not be permitted.
8-903.9 Building sewers and private sewage disposal systems. New building sewers and new private sewage disposal systems shall comply with applicable requirements of the regular code.
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MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS
8-903.10 Fuel-gas piping. Fuel-gas piping shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard.
SECTION 8-904 — ELECTRICAL
8-904.1 General. Electrical systems shall comply with the regular code unless otherwise permitted by this code, or approved by the authority having jurisdiction.
8-904.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any electrical system or portion thereof, the premise wiring, or equipment fixed in place as related to restoration within or attached to a qualified historical building or property.
8-904.1.2 Existing systems, wiring methods and electrical equipment which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.
8-904.1.3 The enforcing agency may approve any alternative to the CHBC which achieves equivalent safety.
8-904.1.4 Archaic methods that do not appear in present codes may remain and may be extended if, in the opinion of the enforcing agency, they constitute a safe installation.
8-904.2 Wiring methods.
CPC § 2025 Medium relevance — show source text
Chapter 7 Sanitary Drainage.
This chapter regulates the design and installation of sanitary drainage systems to ensure they will work as intended. Drainage piping should not be oversized nor undersized, and constructed of approved materials to guard against fouling, deposit of solids, clogging, and with cleanouts so arranged that the pipes may be readily cleaned. The purpose of the sanitary drainage system is to remove effluent discharged from plumbing fixtures and other equipment to an approved point of disposal, such as a public sanitary system or private sewage disposal system.
The basics of a sanitary drainage system include public and private sewage disposal; selection of materials; installation of the building drain and sewer; joining methods for pipe and fittings; drainage fixture units for sizing the drainage system; sumps and ejectors; vent sizing and length of vents; and testing.
Chapter 8 Indirect Wastes.
Chapter 8 regulates indirect waste connections that are required for plumbing fixtures and plumbing appliances dealing with food preparation, dishwashing, potable liquids, and similar equipment. An indirect connection prevents sewage from backing up into a fixture or appliance, thus providing protection against potential health hazards. The waste pipe discharges through an air gap or air break into a waste receptor or standpipe. The protection in the form of an air gap is necessary when the contamination is a potential health hazard or cross connection with the potable water system. Where there is no possibility of contaminating the potable water (nonpotable discharge), the indirect waste pipe may connect in the form of an air break. This method is often preferred to prevent splashing. In addition, health care facilities and special wastes must be protected from contamination that may result from the connection to the drainage system. The waste must be treated to prevent any damage to the piping or sewage treatment process. Waste receptors are sized and designed to prevent splashing and allow for peak discharge conditions.
Chapter 9 Vents.
Chapter 9 regulates the material, design, and installation of vents. A vent system is a pipe or pipes installed in a drainage system that provide a flow of air to and from the system to ventilate it, provide a circulation of air to eliminate trap siphonage, and reduce back-pressure and vacuum surge. In addition, vents provide the rapid and silent flow of waste without exposing occupants of the building to any sewer gases. Proper installation of vents is crucial, as a telltale sign that there is a problem in the drain and vent system is related to the elevation of the horizontal portion of the venting. Venting is not limited to sanitary drainage systems. Venting methods are applicable to other drainage systems such as those for chemical waste, graywater waste, and clear water waste. Sizing the venting system is directly tied to the design of the drainage system. For example, the velocities in the drainage system and its peak flow rates affect the diameters in the venting system. Where the vertical distance between a fixture outlet and trap is excessive, velocities in the entire drainage system will be greater than those in the vent sizing table. All venting methods in this chapter are categorized as either dry vents or wet vents. Vent stacks, stack vents, branch vents, island vents, relief vents, and individual vents are dry vents. Wet vents (horizontal or vertical), circuit vents, combination drain and vents are versions of “wet venting” in which the vent is wetted by drainage flow.
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CRC § 3.3.106.1 Medium relevance — show source text
Private Sewage Disposal System. A septic tank with the effluent discharging into a subsurface disposal field, into one or more seepage pits, or into a combination of subsurface disposal field and seepage pit or of such other facilities as may be permitted under the procedures set forth elsewhere in this code.
Private Sewer. A building sewer that receives the discharge from more than one building drain and conveys it to a public sewer, private sewage disposal system, or another point of disposal. Proportioning System for Medical Air USP. A central supply that produces medical air (USP) reconstituted from oxygen USP and nitrogen NF by means of a mixer or blender.
[NFPA 99:3.3.106.1]
Public or Public Use. Applies to plumbing fixtures that are not defined as private or private use. Public Sewer. A common sewer directly controlled by public authority. Public Water System. A system for the provision to the public of water for human consumption through pipes or other constructed conveyances, if such system has at least fifteen service connections or regularly serves an average of twenty-five individuals daily for at least 60 days per year. Push Fit Fitting. A mechanical fitting where the connection is assembled by pushing the tube or pipe into the fitting and is sealed with an o-ring. PVC. Polyvinyl Chloride.
PVDF. Polyvinylidene Fluoride.
219.0 – Q –
Quick-Disconnect Device. A hand-operated device that provides a means for connecting and disconnecting a hose to a water supply, and that is equipped with a means to shut off the water supply when the device is disconnected. Quick-Disconnect Device, Fuel Gas. A hand-operated device that provides a means for connecting and disconnecting an appliance or an appliance connector to a gas supply and that is equipped with an automatic means to shut off the gas supply when the device is disconnected. [NFPA 54:3.3.27.3]
220.0 – R –
Rainwater. [BSC-CG & HCD 1] Precipitation on any pub- lic or private parcel that has not entered an offsite storm drain system or channel, a flood control channel, or any other stream channel, and has not previously been put to beneficial use. Rainwater Catchment System. [BSC-CG & HCD 1] A facility designed to capture, retain, and store rainwater flow- ing off a building, parking lot, or any other manmade imper- vious surface for subsequent onsite use. Rainwater catchment system is also known as “Rainwater Harvesting System” or “Rainwater Capture System.” Rainwater Storage Tank. The central component of the rainwater catchment system. Also, known as a cistern or rain barrel.
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DEFINITIONS
Receiving Landscape. [BSC-CG & HCD 1] Includes features such as soil, basins, swales, mulch, and plants.
CRC § 714.3 Medium relevance — show source text
714.3 Prohibited Sewer Connection . . . .176
714.4 Commercial Food Waste
Disposer . . . . . . . . . . . . . . . . . . . .176
714.5 Tanks . . . . . . . . . . . . . . . . . . . . . .176
715.0 Building Sewer Materials . . . . . . .176
715.1 Materials . . . . . . . . . . . . . . . . . . . .176
715.2 Joining Methods and Materials . . .176
715.3 Existing Sewers . . . . . . . . . . . . . .176
716.0 Markings . . . . . . . . . . . . . . . . . . . .176
716.1 General . . . . . . . . . . . . . . . . . . . . .176
717.0 Size of Building Sewers . . . . . . . .176
717.1 General . . . . . . . . . . . . . . . . . . . . .176
Table 717.1 Maximum/Minimum Fixture
Unit Loading on Building Sewer Piping . . . . . . . . . . . . . . . .176
717.2 Meat and Poultry Processing Plants . . . . . . . . . . . . . . . . . . . . . .176
718.0 Grade, Support, and Protection of Building Sewers . . .176
718.1 Slope . . . . . . . . . . . . . . . . . . . . . .176
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TABLE OF CONTENTS
718.2 Support . . . . . . . . . . . . . . . . . . . . .176
718.3 Protection from Damage . . . . . . .176
719.0 Cleanouts . . . . . . . . . . . . . . . . . . .177
719.1 Locations . . . . . . . . . . . . . . . . . . .177
719.2 No Additional Cleanouts . . . . . . . .177
719.3 Building Sewer Cleanouts . . . . . .177
719.4 Cleaning . . . . . . . . . . . . . . . . . . . .177
719.5 Access . . . . . . . . . . . . . . . . . . . . .177
719.6 Manholes . . . . . . . . . . . . . . . . . . .177
720.0 Sewer and Water Pipes . . . . . . . .177
720.1 General . . . . . . . . . . . . . . . . . . . . .177
721.0 Location . . . . . . . . . . . . . . . . . . . .177
721.1 Building Sewer . . . . . . . . . . . . . . .177
Table 721.1 Minimum Horizontal Distance Required from Building Sewer . . . .177
721.2 Abutting Lot . . . . . . . . . . . . . . . . .177
722.0 Abandoned Sewers and Sewage Disposal Facilities . . . . . .177
CRC § 1503.8. Medium relevance — show source text
(1) The discharge capacity of a gray water system shall be determined by Section 1503.8. Complex systems have a discharge capacity over 250 gallons (947 L) per day.
(2) Complex systems shall require a construction permit, unless exempted from a construction permit by the Enforcing Agency. The Enforcing Agency shall con- sult with the water purveyor for any public water sys- tem (as defined in Health and Safety Code, Section 116275) providing drinking water to the dwelling or non-residential structure before allowing an exemp- tion from a construction permit. 1503.2 System Requirements. Gray water shall be permitted to be diverted away from a sewer or private sewage disposal system, and discharge to a subsurface irrigation or subsoil irrigation system , or disposal field . The gray water shall be permitted to discharge to a mulch basin residential occupancies . Gray water shall not be used to irrigate root crops or food crops intended for human consumption that comes in contact with soil.
1503.2.1 Surge Capacity. Gray water systems shall be designed to have the capacity to accommodate peak flow rates and distribute the total amount of estimated gray water on a daily basis to a subsurface irrigation field, subsoil irrigation field , disposal field, or mulch
basin without surfacing, ponding, or runoff. A surge tank is required for systems that are unable to accommodate peak flow rates and distribute the total amount of gray water by gravity drainage. The water discharge for gray water systems shall be determined in accordance with Section 1503.8.1 or Section 1503.8.2.
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.
Frequently asked questions
Can I legally connect my rain gutters to the house sanitary sewer?
No. Rain, surface, and subsurface water may not be connected to or discharged into the sanitary drainage system unless the Authority Having Jurisdiction explicitly approves such a connection (§ 714.2).
If there’s no public sewer, do I automatically get to use a septic system?
You may use a private sewage disposal system only if a public sewer is not available and the system is approved by the Authority Having Jurisdiction; design must follow Appendix H where adopted (§ 713.2).
When will a holding tank be required instead of a septic system?
A holding (watertight) tank is required only when the Authority Having Jurisdiction or Health Officer determines it is necessary to prevent contamination, damage, or other hazardous/nuisance conditions (§ 714.5).
Who approves a private sewage disposal system?
The Authority Having Jurisdiction (and sometimes the local Health Officer) approves private disposal systems and any exceptions; Appendix H provides the technical guidance referenced by the AHJ (§ 713.2).
Are there substances that are always forbidden into the sewer?
Yes. The code prohibits depositing ashes, cinders, solids, rags, flammable/poisonous/explosive liquids or gases, oils, grease, or anything that can damage the public or private sewer (see unlawful practices/related sections).
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