CRC · California Residential Code
Backwater valves, sumps and sewage ejectors
If a fixture is lower than the next upstream manhole cover, install an approved backwater valve; if below the sewer crown, drain into a watertight sump and lift with an ejector. Ejectors must be at least 20 gpm and meet solids-passage and discharge-pipe size rules; backwater valves must be accessible and listed.
Last reviewed: July 6, 2026
What the code requires — plain English
Fixtures located on a floor level that is lower than the next upstream manhole cover must be protected from sewage backflow by an approved backwater valve (§ 710.1 ). Where fixtures are below the crown level of the main sewer they must discharge to an approved, watertight sump and the contents be lifted by an approved sewage ejector or pump (§ 710.2, § 710.3 ). Backwater valves and related devices must be accessible for inspection and repair and meet the listed construction standards (§ 710.6 ). As an alternate, macerating toilet systems and pumped-waste systems are permitted where approved and installed per manufacturer and standard requirements (§ 710.13 ).
If a bathroom (or any fixture) is below the next upstream manhole, you must prevent sewer backflow — typically with an approved backwater valve and, if below the main sewer crown, a watertight sump and ejector. § 710.1 is the starting rule.
Requirements in detail
Which fixtures need protection
- Any fixture on a floor level that is lower than the next upstream manhole cover must be protected by an approved backwater valve (§ 710.1 ).
- Fixtures on that floor level that are not below the next upstream manhole cover do not require a backwater valve (§ 710.1 ).
Sewage ejector / pump minimum performance and sizing
Key performance and sizing rules for ejectors that receive toilets or urinals:
- Minimum discharge capacity: 20 gpm (1.26 L/s) (§ 710.3 ).
- Single-dwelling ejector must be able to pass a 1-1/2 inch (38 mm) diameter solid ball; discharge piping must include a backwater valve and a gate valve and be not less than 2 inches (50 mm) in diameter (§ 710.3 ).
- For other than single-dwelling units the ejector must pass a 2 inch (51 mm) solid ball; discharge piping must have a backwater and gate valve and be not less than 3 inches (80 mm) in diameter (§ 710.3 ).
- Note (HCD): where a pump serves a water closet, the minimum pump or discharge pipe size shall be not less than 2 inches (50 mm) (administrative HCD note in the section) .
Backwater valve construction, placement and access
- Backwater valves must be located where accessible for inspection and repair; if not continuously exposed they must be enclosed in a masonry pit with an adequately sized removable cover (§ 710.6 ).
- Valves shall comply with ASME A112.14.1 or IAPMO IGC 305 and be constructed of approved materials (cast-iron, plastic, copper alloy, or approved materials) with noncorrosive bearings/seats and a positive mechanical seal (§ 710.6 ).
- Such valves shall remain open during periods of low flows to avoid screening of solids and shall not restrict capacity or cause excessive turbulence at peak loads. Access covers, unless otherwise listed, shall be bolted with gasket and each valve must bear the manufacturer’s name cast into the body/cover (§ 710.6 .
Macerating toilet systems and pumped waste
- Macerating toilet systems or pumped-waste systems are permitted as an alternate to sewage pump systems where approved by the Authority Having Jurisdiction and must comply with ASME A112.3.4/CSA B45.9 and manufacturer instructions (§ 710.13 ).
- Sump for macerating system must be watertight and gastight (§ 710.13.1 ).
- Discharge piping must be sized per manufacturer instructions and be not less than 3/4 inch (20 mm); developed length must not exceed manufacturer’s instruction; a check valve and fullway-type shutoff valve shall be located within the discharge line or internal to the device (§ 710.13.2 .
- Venting of the fixtures and the sump must follow code and manufacturer instructions; the sump vent may connect to fixture venting when permitted (§ 710.13.3 .
Quick-reference decision table
| Decision question | Minimum / required value | Code Reference |
|---|---|---|
| Ejector minimum discharge capacity | 20 gpm (1.26 L/s) | § 710.3 |
| Minimum solids passage (single dwelling ejector) | 1-1/2 in (38 mm) | § 710.3 |
| Minimum solids passage (other than single dwelling) | 2 in (51 mm) | § 710.3 |
| Minimum ejector discharge pipe (single dwelling) | 2 in (50 mm) | § 710.3 |
| Minimum ejector discharge pipe (other than single dwelling) | 3 in (80 mm) | § 710.3 |
| Backwater valve compliance standards | ASME A112.14.1 or IAPMO IGC 305 | § 710.6 |
| Macerator discharge min. diameter | 3/4 in (20 mm) | § 710.13.2 |
| Sump construction | Watertight (macerator sump: watertight & gastight) | § 710.2, § 710.13.1 |
| Backwater valve accessibility | Accessible for inspection and repair; enclosed in masonry pit if not exposed | § 710.6 |
Exceptions & special cases
- Fixtures on a floor level that are not below the next upstream manhole cover are not required to be protected by a backwater valve (§ 710.1 ).
- The Authority Having Jurisdiction may approve macerating or pumped-waste systems as an alternate to a conventional sewage ejector; such systems must follow manufacturer instructions and listed standards (§ 710.13 ).
- Administrative/HCD note: Where a pump serves a water closet, a minimum pump or discharge pipe size of 2 inches (50 mm) is mandated in that HCD note accompanying the ejector sizing text (see the section commentary) .
- Backwater valves must remain open at low flows to avoid trapping solids that could block flow — this is a required construction/operation characteristic, not an optional feature (§ 710.6 .
Common mistakes
- Installing the backwater valve in an inaccessible location (contrary to § 710.6) — it must be accessible for inspection/repair and, if enclosed, have a removable cover for the pit .
- Using a non-listed or improperly constructed valve that does not meet ASME A112.14.1 or IAPMO IGC 305 or that restricts flow during peak loads (§ 710.6) .
- Omitting the required backwater valve or sump/ejector when a fixture is below the next upstream manhole (§ 710.1, § 710.2) .
- Selecting an ejector or pump with insufficient capacity or solids-passage capability (must be ≥ 20 gpm and meet required ball passage for the occupancy) (§ 710.3) .
- For macerating systems: failing to follow manufacturer discharge diameter or maximum developed length requirements or not including the required check and fullway shutoff valves (§ 710.13.2) .
- Forgetting to label cleanouts that pass through a backwater valve with the permanent label “backwater valve downstream” as required in § 710.1 .
Worked example — basement bathroom with a toilet below the sewer crown
Scenario: A single-family house has a basement bathroom with a toilet whose finished-floor outlet is below the crown of the main sewer and below the next upstream manhole.
Steps and how the code applies:
- Because the toilet is lower than the next upstream manhole cover, install an approved backwater valve in the house drain serving that floor (§ 710.1) .
- Because the fixtures are below the crown of the main sewer, the toilet discharge must go into an approved watertight sump and be lifted by a sewage ejector (§ 710.2, § 710.3) .
- Select an ejector meeting the minimum: 20 gpm discharge capacity and capable of passing a 1-1/2 inch (38 mm) ball (single-dwelling requirement). The ejector discharge piping must have a backwater valve and a gate valve and be not less than 2 inches (50 mm) in diameter (§ 710.3) .
- Locate the backwater valve and gate valve where they are accessible; if installed below grade or not continuously exposed, enclose in a masonry pit with removable cover per § 710.6 .
- Sizing check (building drain capacity): use § 710.5 guidance (two fixture units allowed per gallon per minute). For a 20 gpm ejector, that equates to 40 fixture units equivalency when assessing impact on receiving building drain/sewer capacity (§ 710.5) .
Result: The basement toilet is code-compliant if you install the watertight sump, a 20 gpm ejector capable of 1-1/2" solids passage, a discharge line ≥2" with backwater and gate valve, and make the valve accessible per § 710.6. Cite: § 710.1, § 710.2, § 710.3, § 710.6.
Related provisions (useful cross-references)
- § 710.2 — Sewage discharge to watertight sump and lift requirements.
- § 710.4 — Discharge line materials and required check/backwater and gate/ball valve arrangement (discharge line details).
- § 710.5 — Size of building drains and sewers receiving pump/ejector discharge (fixture unit conversion).
- § 710.8 — Sump and receiving tank construction requirements (watertight construction).
- § 710.9 — Alarm and dual-pump requirements for public-use occupancies.
- § 710.10 — Sump covers and venting requirements (vent sizing and vent connections).
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 710.2 High relevance — show source text
710.2 Sewage Discharge. Drainage piping serving fixtures that are located below the crown level of the main sewer shall discharge into an approved watertight sump or receiving tank, so located as to receive the sewage or wastes by gravity. From such sump or receiving tank, the sewage or other liquid wastes shall be lifted and discharged into the building drain or building sewer by approved ejectors, pumps, or other equally efficient approved mechanical devices. 710.3 Sewage Ejector and Pumps. A sewage ejector or sewage pump receiving the discharge of water closets or urinals:
(1) Shall have a discharge capacity of not less than 20 gpm (1.26 L/s).
(2) In single dwelling units, the ejector or pump shall be capable of passing an 1 [1] ⁄ 2 inch (38 mm) diameter solid ball, and the discharge piping of each ejector or pump
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SANITARY DRAINAGE
shall have a backwater valve and gate valve, and be not less than 2 inches (50 mm) in diameter.
(3) In other than single-dwelling units, the ejector or pump shall be capable of passing a 2 inch (51 mm) diameter solid ball, and the discharge piping of each ejector or pump shall have a backwater valve and gate valve, and be not less than 3 inches (80 mm) in diameter.
[HCD 1 & HCD 2] The minimum size of any pump or any discharge pipe from a sump having a water closet connected thereto shall be not less than 2 inches (50 mm). 710.4 Discharge Line. The discharge line from such ejector, pump, or another mechanical device shall be of approved pressure rated material and be provided with an accessible backwater or swing check valve and gate or ball valve. Where the gravity drainage line to which such discharge line connects is horizontal, the method of connection shall be from the top through a wye branch fitting. The gate or ball valve shall be located on the discharge side of the backwater or check valve.
Gate or ball valves, where installed in drainage piping, shall be fullway type with working parts of corrosion-resistant metal. Sizes 4 inches (100 mm) or more in diameter shall have cast-iron bodies and sizes less than 4 inches (100 mm), cast-iron or copper alloy bodies. 710.5 Size of Building Drains and Sewers. Building drains or building sewers receiving a discharge from a pump or ejector shall be adequately sized to prevent overloading. Two fixture units shall be allowed for each gallon per minute (L/s) of flow. 710.6 Backwater Valves. Backwater valves, gate valves, fullway ball valves, unions, motors, compressors, air tanks, and other mechanical devices required by this section shall be located where they will be accessible for inspection and repair and, unless continuously exposed, shall be enclosed in a masonry pit fitted with an adequately sized removable
cover.
Backwater valves shall comply with ASME A112.14.1 or IAPMO IGC 305, and have bodies of cast-iron, plastic, copper alloy, or other approved materials; shall have noncorrosive bearings, seats, and self-aligning discs; and shall be constructed to ensure a positive mechanical seal.
CRC § 710.5 High relevance — show source text
Gate or ball valves, where installed in drainage piping, shall be fullway type with working parts of corrosion-resistant metal. Sizes 4 inches (100 mm) or more in diameter shall have cast-iron bodies and sizes less than 4 inches (100 mm), cast-iron or copper alloy bodies. 710.5 Size of Building Drains and Sewers. Building drains or building sewers receiving a discharge from a pump or ejector shall be adequately sized to prevent overloading. Two fixture units shall be allowed for each gallon per minute (L/s) of flow. 710.6 Backwater Valves. Backwater valves, gate valves, fullway ball valves, unions, motors, compressors, air tanks, and other mechanical devices required by this section shall be located where they will be accessible for inspection and repair and, unless continuously exposed, shall be enclosed in a masonry pit fitted with an adequately sized removable
cover.
Backwater valves shall comply with ASME A112.14.1 or IAPMO IGC 305, and have bodies of cast-iron, plastic, copper alloy, or other approved materials; shall have noncorrosive bearings, seats, and self-aligning discs; and shall be constructed to ensure a positive mechanical seal. Such backwater valves shall remain open during periods of low flows to avoid screening of solids and shall not restrict capacities or cause excessive turbulence during peak loads. Unless otherwise listed, valve access covers shall be bolted type with gasket, and each valve shall bear the manufacturer’s name cast into the body and the cover. 710.7 Drainage and Venting Systems. The drainage and venting systems, in connection with fixtures, sumps, receiving tanks, and mechanical waste-lifting devices shall be installed under the same requirements as provided for in this code for gravity systems. 710.8 Sump and Receiving Tank Construction. Sumps and receiving tanks shall be watertight and shall be constructed of concrete, metal, or other approved materials. Where constructed of poured concrete, the walls and bottom shall be adequately reinforced and designed to recognized acceptable standards. Metal sumps or tanks shall be of such
thickness as to serve their intended purpose and shall be treated internally and externally to resist corrosion.
710.9 Alarm. Such sumps and receiving tanks shall be automatically discharged and, wherein a “public use” occupancy, shall be provided with dual pumps or ejectors arranged to function alternately in normal use and independently. Such pumps shall be capable of running continuously in case of overload or mechanical failure of one of the pumps or ejectors. The pumps shall have an audio and visual alarm, readily accessible, that signals pump failure or an overload condition. The lowest inlet shall have a clearance of not less than 2 inches (51 mm) from the high-water or “starting” level of the sump. 710.10 Sump and Receiving Tank Covers and Vents. Sumps and receiving tanks shall be provided with substantial covers having a bolt-and-gasket-type manhole or equivalent opening to permit access for inspection, repairs, and cleaning. The top shall be provided with a vent pipe that shall extend separately through the roof or, where permitted, be combined with other vent pipes. Such vent shall be large enough to maintain atmospheric pressure within the sump under normal operating conditions and, in no case, shall be less in size than that required by Table 703.2 for the number and type of fixtures discharging into the sump, nor less than 1 [1] ⁄ 2 inches (40 mm) in diameter.
CRC § 707.12 High relevance — show source text
707.12 Countersunk Cleanout Plugs. Countersunk cleanout plugs shall be installed where raised heads cause a hazard.
707.13 Hubless Blind Plugs. Where a hubless blind plug is used for a required cleanout, the complete coupling and plug shall be accessible for removal or replacement. 707.14 Trap Arms. Cleanouts for trap arms shall be installed in accordance with Section 1002.3.
708.0 Grade of Horizontal Drainage Piping. 708.1 General. Building drain and other horizontal drainage piping shall be run in practical alignment and a uniform slope of not less than [1] ⁄ 4 inch per foot (20.8 mm/m) or 2 percent toward the point of disposal.
Where it is impractical due to the depth of the street sewer, structural features, or to the arrangement of a building or structure to obtain a slope of [1] ⁄ 4 inch per foot (20.8 mm/m) or 2 percent, building drain piping 4 inches (100 mm) or larger in diameter shall be permitted to have a slope of not less than [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent, when first approved by the Authority Having Jurisdiction.
709.0 Gravity Drainage Required. 709.1 General. Where practicable, plumbing fixtures shall be drained to the public sewer or private sewage disposal system by gravity.
710.0 Drainage of Fixtures Located Below the Next Upstream Manhole or Below the Main Sewer Level.
710.1 Backflow Protection. Fixtures installed on a floor level that is lower than the next upstream manhole cover of the public, or private sewer shall be protected from backflow of sewage by installing an approved type of backwater valve. Fixtures on such floor level that are not below the next upstream manhole cover shall not be required to be protected by a backwater valve. Fixtures on floor levels above such elevation shall not discharge through the backwater valve. Cleanouts for drains that pass through a backwater valve shall be clearly identified with a permanent label stating “backwater valve downstream.”
710.2 Sewage Discharge. Drainage piping serving fixtures that are located below the crown level of the main sewer shall discharge into an approved watertight sump or receiving tank, so located as to receive the sewage or wastes by gravity. From such sump or receiving tank, the sewage or other liquid wastes shall be lifted and discharged into the building drain or building sewer by approved ejectors, pumps, or other equally efficient approved mechanical devices. 710.3 Sewage Ejector and Pumps. A sewage ejector or sewage pump receiving the discharge of water closets or urinals:
(1) Shall have a discharge capacity of not less than 20 gpm (1.26 L/s).
(2) In single dwelling units, the ejector or pump shall be capable of passing an 1 [1] ⁄ 2 inch (38 mm) diameter solid ball, and the discharge piping of each ejector or pump
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SANITARY DRAINAGE
shall have a backwater valve and gate valve, and be not less than 2 inches (50 mm) in diameter.
CRC § 1503.4 Medium relevance — show source text
Table 1503.4
Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1504.1
SUBSURFACE
IRRIGATION FIELDS . . . . . . . . . . . . . . . .221.0, 1503.2.1,
1504.2 – 1504.4, 1504.5,
1504.5.2
SUDS RELIEF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .711.0
SUMPS
Boiler room, installation . . . . . . . . . . . . . . .810.1, 810.3
Building, backwater
devices . . . . . . . . . . . . . . .710.1, 710.3, 710.4, 710.6
Building drainage
systems below sewer level . . . . . . . . . . . . . . . . . . .710.2
Condensers . . . . . . . . . . . . . . . . . . . .810.0, Table 810.1
Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . .810.2
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221.0
Macerating toilet systems . . . . . . . . . . . . . . . . .710.13.1
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INDEX
Pump connection permitted . . . . .710.2 – 710.5, 710.9,
805.1, 1101.6.2, 1101.7
Pump discharges, conversion
to fixture units . . . . . . . . . . . . . . . . . . . . .702.3, 710.5
Sewage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .710.2
Sizing, sewage
ejector and pumps . . . . . . . . . . . . . . . . . . . . . . .710.3
Storm drainage . . . . . . . . . . . .1101.6.2, 1101.6.3, 1101.7,
1101.10, 1101.11, 1101.14
Vents . . . . . . . . . . . . . . . . . . . . .710.7, 710.10, 710.13.3,
810.1, Table 810.1
Water supply inlets . . . . . . . . . . . . . . . . . . . . . . .603.5.5
SUPPLY, WATER
Fittings, fixtures . . . . . . . . . . . . . . . . . . . . . . . . . . .402.7
CRC § 710.0 Medium relevance — show source text
710.0 Drainage of Fixtures Located Below the Next Upstream Manhole or Below the Main
Sewer Level . . . . . . . . . . . . . . . . .173
710.1 Backflow Protection . . . . . . . . . . .173
710.2 Sewage Discharge . . . . . . . . . . . .173
710.3 Sewage Ejector and Pumps . . . . .173
710.4 Discharge Line . . . . . . . . . . . . . . .174
710.5 Size of Building Drains and Sewers . . . . . . . . . . . . . . . . . . . . .174
710.6 Backwater Valves . . . . . . . . . . . . .174
710.7 Drainage and Venting Systems . . .174
710.8 Sump and Receiving Tank Construction . . . . . . . . . . . . . . . . .174
710.9 Alarm . . . . . . . . . . . . . . . . . . . . . .174
710.10 Sump and Receiving Tank Covers and Vents . . . . . . . . . . . . .174
710.11 Air Tanks . . . . . . . . . . . . . . . . . . .174
710.12 Grinder Pump Ejector . . . . . . . . . .174
710.13 Macerating Toilet Systems and Pumped Waste Systems . . . .174
711.0 Suds Relief . . . . . . . . . . . . . . . . . .175
711.1 General . . . . . . . . . . . . . . . . . . . . .175
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
CRC § 707.2 Medium relevance — show source text
Table 707.2 Cleanout Materials for Drain, Waste, and Vent . . . . . . . . . . . . . .172
707.3 Watertight and Gastight . . . . . . . .172
707.4 Location . . . . . . . . . . . . . . . . . . . .172
707.5 Cleaning . . . . . . . . . . . . . . . . . . . .173
707.6 Extension . . . . . . . . . . . . . . . . . . .173
707.7 Interceptor . . . . . . . . . . . . . . . . . .173
707.8 Access . . . . . . . . . . . . . . . . . . . . .173
707.9 Clearance . . . . . . . . . . . . . . . . . . .173
707.10 Fittings . . . . . . . . . . . . . . . . . . . . .173
707.11 Pressure Drainage Systems . . . . .173
707.12 Countersunk Cleanout Plugs . . . .173
707.13 Hubless Blind Plugs . . . . . . . . . . .173
707.14 Trap Arms . . . . . . . . . . . . . . . . . . .173
708.0 Grade of Horizontal Drainage Piping . . . . . . . . . . . . . . . . . . . . . .173
708.1 General . . . . . . . . . . . . . . . . . . . . .173
709.0 Gravity Drainage Required . . . . . .173
709.1 General . . . . . . . . . . . . . . . . . . . . .173
710.0 Drainage of Fixtures Located Below the Next Upstream Manhole or Below the Main
Sewer Level . . . . . . . . . . . . . . . . .173
710.1 Backflow Protection . . . . . . . . . . .173
710.2 Sewage Discharge . . . . . . . . . . . .173
710.3 Sewage Ejector and Pumps . . . . .173
710.4 Discharge Line . . . . . . . . . . . . . . .174
710.5 Size of Building Drains and Sewers . . . . . . . . . . . . . . . . . . . . .174
710.6 Backwater Valves . . . . . . . . . . . . .174
710.7 Drainage and Venting Systems . . .174
710.8 Sump and Receiving Tank Construction . . . . . . . . . . . . . . . . .174
710.9 Alarm . . . . . . . . . . . . . . . . . . . . . .174
710.10 Sump and Receiving Tank Covers and Vents . . . . . . . . . . . . .174
710.11 Air Tanks . . . . . . . . . . . . . . . . . . .174
710.12 Grinder Pump Ejector . . . . . . . . . .174
710.13 Macerating Toilet Systems and Pumped Waste Systems . . . .174
711.0 Suds Relief . . . . . . . . . . . . . . . . . .175
CRC § 19.1 Medium relevance — show source text
Such subsoil drains shall be permitted to be positioned inside or outside of the footing, shall be of perforated or open-jointed approved drain tile or pipe, not less than 3 inches (80 mm) in diameter, and shall be laid in gravel, slag, crushed rock, approved [3] ⁄ 4 of an inch (19.1 mm) crushed, recycled glass aggregate, or other approved porous material with not less than 4 inches (102 mm) surrounding the pipe. Filter media shall be provided for exterior subsoil piping. Exception: [HCD 1 & HCD 2] Subsoil drains are mandatory only when required by the Authority Having Jurisdiction due to geological conditions.
TABLE 1101.4.6
MATERIALS FOR SUBSOIL DRAINPIPE AND FITTINGS
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STORM DRAINAGE
1101.6.1 Discharge. Subsoil drains shall be piped to a storm drain, to an approved water course, to the front street curb or gutter, to an alley, or the discharge from the subsoil drains shall be conveyed to the alley by a concrete gutter. Where a continuously flowing spring or groundwater is encountered, subsoil drains shall be piped to a storm drain or an approved water course. 1101.6.2 Sump. Where it is not possible to convey the drainage by gravity, subsoil drains shall discharge to an accessible sump provided with an approved automatic electric pump. The sump shall be not less than 15 inches (381 mm) in diameter, 18 inches (457 mm) in depth, and provided with a fitted cover. The sump pump shall have an adequate capacity to discharge water coming into the sump as it accumulates to the required discharge point, and the capacity of the pump shall be not less than 15 gallons per minute (gpm) (0.95 L/s). The discharge piping from the sump pump shall be not less than 1 [1] ⁄ 2 inches (40 mm) in diameter and have a union or other approved quick-disconnect assembly to make the pump accessible for servicing. 1101.6.3 Splash Blocks. For separate dwellings not serving continuously flowing springs or groundwater, the sump discharge pipe shall be permitted to discharge onto a concrete splash block with a minimum length of 24 inches (610 mm). This pipe shall be within 4 inches (102 mm) of the splash block and positioned to direct the flow parallel to the recessed line of the splash block.
1101.6.4 Backwater Valve. Subsoil drains subject to backflow where discharging into a storm drain shall be provided with a backwater valve in the drain line so located as to be accessible for inspection and maintenance. 1101.6.5 Open Area. Nothing in Section 1101.6 shall prevent drains that serve either subsoil drains or areaways of a detached building from discharging to a properly graded open area, provided that:
(1) They do not serve continuously flowing springs or groundwater.
(2) The point of discharge is not less than 10 feet (3048 mm) from a property line.
CRC § 408.8.3 Medium relevance — show source text
Sheet . . . . . . . . . . . . . . . . . . . . . . .408.8.3, 701.5, 906.6
Water supply . . . . . . . . . . . . . . . . . . . . . .604.2, 604.2.1
LEADERS
Cleanouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1101.13
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214.0
Installed outside . . . . . . . . . . . . . . . . . . . . . . . . .1101.4.3
Leaders, conductors, and connections . . . . . . . .1101.16 Roof drainage . . . . . . . . . . . . . . . . . . . . . . . . . . .1101.12 Size of leaders, conductors, and
storm drains . . . . . . . . . . . . . . . . . . . . . . . . . . .1103.0
Sizing roof drains, leaders, and vertical rainwater piping . . . . . . . . . . . . .Table 1103.1 Traps on storm drains and leaders . . . . . . . . . . .1101.15
LIMITED-DENSITY OWNER-BUILT
RURAL DWELLING
Connections to plumbing system . . . . . . . . . . . . . .304.1
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214.0
Disposal of liquid waste . . . . . . . . . . . . . . . . . . . . .303.1 Water supply and flushing . . . . . . . . . . . . . . . . . . .601.2 LIQUEFIED PETROLEUM
GAS (LP-GAS) . . . . . . . . . . . . . . . 214.0, 1202.1, 1208.4.1,
1208.5.6.3, 1208.5.10.4,
1212.11, E 401.2,
E 403.1, E 403.10
LIQUID WASTES . . . . . . . . . . . . . . . . .214.0, 303.0, L 302.0
LISTED . . . . . . . . . . . . . . . . . . . . . . . .214.0, 301.2, 402.6.2,
501.1
LISTING AGENCY . . . . . . . . . . . . . . . . . . . . . . .214.0, 301.2
LOCATION OF
Backwater valves . . . . . . . . .710.1, 710.3, 710.4, 710.6,
1006.0, 1101.6.4, 1503.2.3,
1503.9.1, 1503.9.7
CRC § 0.95 Medium relevance — show source text
The sump shall be not less than 15 inches (381 mm) in diameter, 18 inches (457 mm) in depth, and provided with a fitted cover. The sump pump shall have an adequate capacity to discharge water coming into the sump as it accumulates to the required discharge point, and the capacity of the pump shall be not less than 15 gallons per minute (gpm) (0.95 L/s). The discharge piping from the sump pump shall be not less than 1 [1] ⁄ 2 inches (40 mm) in diameter and have a union or other approved quick-disconnect assembly to make the pump accessible for servicing. 1101.6.3 Splash Blocks. For separate dwellings not serving continuously flowing springs or groundwater, the sump discharge pipe shall be permitted to discharge onto a concrete splash block with a minimum length of 24 inches (610 mm). This pipe shall be within 4 inches (102 mm) of the splash block and positioned to direct the flow parallel to the recessed line of the splash block.
1101.6.4 Backwater Valve. Subsoil drains subject to backflow where discharging into a storm drain shall be provided with a backwater valve in the drain line so located as to be accessible for inspection and maintenance. 1101.6.5 Open Area. Nothing in Section 1101.6 shall prevent drains that serve either subsoil drains or areaways of a detached building from discharging to a properly graded open area, provided that:
(1) They do not serve continuously flowing springs or groundwater.
(2) The point of discharge is not less than 10 feet (3048 mm) from a property line.
(3) It is impracticable to discharge such drains to a storm drain, to an approved water course, to the front street curb or gutter, or to an alley. 1101.7 Building Subdrains. Building subdrains located below the public sewer level shall discharge into a sump or receiving tank, the contents of which shall be automatically lifted and discharged into the drainage system as required for building sumps. 1101.8 Areaway Drains. Open subsurface space adjacent to a building, serving as an entrance to the basement or cellar of a building, shall be provided with a drain or drains. The areaway drains shall be not less than 2 inches (50 mm) in diameter for areaways at a maximum of 100 square feet (9.29 m [2] ) in area, and shall be discharged in the manner provided for subsoil drains not serving continuously flowing springs or groundwater (see Section 1101.6.1). Areaways exceeding 100 square feet (9.29 m [2] ) shall not drain into subsoil drains.
The drains for areaways exceeding 100 square feet (9.29 m [2] ) shall be sized in accordance with Table 1103.2.
CRC § 710.8 Medium relevance — show source text
710.8 Sump and Receiving Tank Construction. Sumps and receiving tanks shall be watertight and shall be constructed of concrete, metal, or other approved materials. Where constructed of poured concrete, the walls and bottom shall be adequately reinforced and designed to recognized acceptable standards. Metal sumps or tanks shall be of such
thickness as to serve their intended purpose and shall be treated internally and externally to resist corrosion.
710.9 Alarm. Such sumps and receiving tanks shall be automatically discharged and, wherein a “public use” occupancy, shall be provided with dual pumps or ejectors arranged to function alternately in normal use and independently. Such pumps shall be capable of running continuously in case of overload or mechanical failure of one of the pumps or ejectors. The pumps shall have an audio and visual alarm, readily accessible, that signals pump failure or an overload condition. The lowest inlet shall have a clearance of not less than 2 inches (51 mm) from the high-water or “starting” level of the sump. 710.10 Sump and Receiving Tank Covers and Vents. Sumps and receiving tanks shall be provided with substantial covers having a bolt-and-gasket-type manhole or equivalent opening to permit access for inspection, repairs, and cleaning. The top shall be provided with a vent pipe that shall extend separately through the roof or, where permitted, be combined with other vent pipes. Such vent shall be large enough to maintain atmospheric pressure within the sump under normal operating conditions and, in no case, shall be less in size than that required by Table 703.2 for the number and type of fixtures discharging into the sump, nor less than 1 [1] ⁄ 2 inches (40 mm) in diameter. Where the preceding requirements are met and the vent, after leaving the sump, is combined with vents from fixtures discharging into the sump, the size of the combined vent need not exceed that required for the total number of fixtures discharging into the sump. No vent from an air-operating sewage ejector shall combine with other vents. 710.11 Air Tanks. Air tanks shall be so proportioned as to be of equal cubical capacity to the ejectors connected in addition to that in which there shall be maintained an air pressure of not less than 2 pounds per foot (lb/ft) (3 kg/m) of height the sewage is to be raised. No water-operated ejectors shall be permitted. 710.12 Grinder Pump Ejector. Grinder pumps shall be permitted to be used. 710.12.1 Discharge Piping. The discharge piping shall be sized in accordance with the manufacturer’s installation instructions and shall be not less than 1 [1] ⁄ 4 inches (32 mm) in diameter. A check valve and fullwaytype shutoff valve shall be located on the discharge line. 710.13 Macerating Toilet Systems and Pumped Waste Systems. Fixtures shall be permitted to discharge to a macerating toilet system, or pumped waste system shall be permitted as an alternate to a sewage pump system where approved by the Authority Having Jurisdiction. Such systems shall comply with ASME A112.3.4/CSA B45.9 and shall be installed in accordance with the manufacturer’s installation
instructions.
CRC § 104.0 Medium relevance — show source text
Rectangular scuppers . . . . . . . . . . . . . . . . . . . .D 104.0
Sewage ejectors or pumps . . . . . . . . . . . . . . . . . .710.3
Sump pump . . . . . . . . . . . . . . . . . . . . . . . . . . . .1101.6.2
Water heaters . . . . . . . . . . . . . . . . . . .501.1, Table 501.1(1)
CAST-IRON PIPE
Approved standards . . . . . . . . . . . . . . . . . . . . . .301.2.4
Discharge line from ejectors . . . . . . . . . . . . . . . . .710.4
Drainage piping . . . . . . . . . . . . . . . . . . . . . . . . . . .701.2
Fittings . . . . . . . . . . . . . . . . . .301.2.3, 604.6, 1208.5.9.5
Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . . .1208.5.11.1
Joining . . . . . . . . . . . . . . . . . . . . . . . . . .705.2, 705.10.1
Prohibited use . . . . . . . . . . . . . . . . . . . .316.1, 1208.5.2
CAULKED JOINTS . . . . . . . . . . . . . . . . . . . . . . . . . .705.2.1
CAULKING FERRULES . . . . . . . . . . . . . .701.6, Table 701.6
CERTIFICATION
Backflow assembly testers . . . . . . . . . . . . .205.0, 603.2
Medical gas or medical
vacuum installers . . . . . . . . . . . . . . . . . . . . . .1323.10
Medical gas or medical
vacuum systems . . . . . . . . . . . . . . . . . . . . . . .1306.0
Pipe welder, definition . . . . . . . . . . . . . . . . . . . . . .225.0
Residential fire sprinklers installers . . . . . . . . . . . .612.1
CESSPOOL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .H 801.1
Abandoned . . . . . . . . . . . . . . . . . . . . . . .722.0, H 1101.0
Connections to sewer prohibited . . . . . . . . . . . . . .714.3
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205.0
CHECK VALVES
In drainage systems . . . . . . . . . . . . . . .710.4, 710.12.1,
710.13.2, 1004.2
CRC § 214.0 Medium relevance — show source text
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214.0
Disposal of liquid waste . . . . . . . . . . . . . . . . . . . . .303.1 Water supply and flushing . . . . . . . . . . . . . . . . . . .601.2 LIQUEFIED PETROLEUM
GAS (LP-GAS) . . . . . . . . . . . . . . . 214.0, 1202.1, 1208.4.1,
1208.5.6.3, 1208.5.10.4,
1212.11, E 401.2,
E 403.1, E 403.10
LIQUID WASTES . . . . . . . . . . . . . . . . .214.0, 303.0, L 302.0
LISTED . . . . . . . . . . . . . . . . . . . . . . . .214.0, 301.2, 402.6.2,
501.1
LISTING AGENCY . . . . . . . . . . . . . . . . . . . . . . .214.0, 301.2
LOCATION OF
Backwater valves . . . . . . . . .710.1, 710.3, 710.4, 710.6,
1006.0, 1101.6.4, 1503.2.3,
1503.9.1, 1503.9.7
Fixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . .308.0, 402.0
Fuel gas meters . . . . . . . . . . . . . . . . .1208.7 – 1208.7.3,
E 402.4 – E 402.4.2
Fuel gas valves . . . . . . . . . . . . . . . . .1210.9 – 1210.9.4, 1212.5.3, 1212.6, E 402.3
Interceptors and separators . . . . . . . . . . . .1009.3, 1009.5 Medical gas and medical vacuum system valves . . . . . . . . . . . .1314.0 Plumbing system or sewer on lot . . . . . . . .307.0, 721.1,
Table 721.1
Private sewage disposal system . . . . . . . . . . . . .H 101.8 Water heaters . . . . . . . . . .504.1, 504.3 – 504.6, 506.3,
507.2, 507.5, 507.10,
507.12 – 507.15, 507.24,
507.25, 507.26
LOT, DEFINITION . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214.0
LOW HAZARD . . . . . . . . . . . . . . . . . . . . .214.0, Table 603.2
Frequently asked questions
When exactly is a backwater valve required?
A backwater valve is required where fixtures are on a floor level lower than the next upstream manhole cover — install an approved backwater valve for those fixtures per § 710.1.
Can I use a macerating toilet instead of a sump and ejector?
Yes — a macerating toilet system or pumped-waste system is permitted as an alternate where approved by the Authority Having Jurisdiction and when installed per ASME A112.3.4/CSA B45.9 and the manufacturer’s instructions (§ 710.13).
What minimum pump capacity do I need if a toilet discharges to an ejector?
The ejector must have a minimum discharge capacity of 20 gpm (1.26 L/s) per § 710.3.
How large must the ejector discharge pipe be for a single-family home?
For a single dwelling with water closet/urinal discharge the discharge pipe shall be not less than 2 inches (50 mm) and have a backwater valve and gate valve (§ 710.3).
Do backwater valves need to be listed or meet a standard?
Yes — backwater valves must comply with ASME A112.14.1 or IAPMO IGC 305 and meet the construction/accessibility requirements in § 710.6.
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