Stormwater, Sumps & Rainwater

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

• CRC § 1101.13.1 Medium relevance — show source text

  1101.13.1 Rain Leaders and Conductors. Rain leaders and conductors connected to a building storm sewer shall have a cleanout installed at the base of the

  leader or conductor before it connects to the horizontal

  drain.

  1101.14 Rainwater Sumps. Rainwater sumps serving “public use” occupancy buildings shall be provided with dual pumps arranged to function alternately in the case of overload or mechanical failure. Pumps rated 600 V or less shall comply with UL 778 and shall be installed in accordance with the manufacturer’s installation instructions.

  1101.15 Traps on Storm Drains and Leaders. Leaders and storm drains, where connected to a combined sewer, shall be trapped. Floor and area drains connected to a storm drain shall be trapped.

  Exception: Traps shall not be required where roof drains, rain leaders, and other inlets are at locations permitted under Section 906.0, Vent Termination.

  1101.15.1 Where Not Required. No trap shall be required for leaders or conductors that are connected to a sewer carrying storm water exclusively. 1101.15.2 Trap Size. Traps, where installed for individual conductors, shall be the same size as the horizontal drain to which they are connected.

  1101.15.3 Method of Installation of Combined Sewer. Individual storm-water traps shall be installed on the stormwater drain branch serving each storm-water inlet, or a single trap shall be installed in the main storm drain just before its connection with the combined building sewer. Such traps shall be provided with an accessible cleanout on the outlet side of the trap.

  1101.16 Leaders, Conductors, and Connections. Leaders or conductors shall not be used as soil, waste, or vent pipes nor shall soil, waste, or vent pipes be used as leaders or conductors.

  1101.16.1 Protection of Leaders. Leaders installed along alleyways, driveways, or other locations where exposed to damage shall be protected by metal guards, recessed into the wall, or constructed from the ferrous pipe. 1101.16.2 Combining Storm with Sanitary Drainage. The sanitary and storm drainage system of a building shall be entirely separate, except where a combined sewer is used, in which case the building storm drain shall be connected in the same horizontal plane through a single wye fitting to the combined building sewer not less than 10 feet (3048 mm) downstream from a soil stack.

  1102.0 Roof Drains.

  1102.1 Applications. Roof drains shall be constructed of aluminum, cast-iron, copper alloy of not more than 15 percent zinc, leaded nickel bronze, stainless steel, ABS, PVC, polypropylene, polyethylene, or nylon and shall comply with ASME A112.3.1 or ASME A112.6.4.

  1102.2 Dome Strainers Required. Roof drains shall have domed strainers.

  Exception: Roof drain strainers for use on sun decks, parking decks, and similar areas that are normally serviced and maintained, shall be permitted to be of the flat surface type. Such roof drain strainers shall be level with the deck.

• CRC § 1101.12.2.2 Medium relevance — show source text

  1101.12.2.2 Secondary Roof Drain. Secondary roof drains shall be provided. The secondary roof drains shall be located not less than 2 inches (51 mm) above the roof surface. The maximum height of the roof drains shall be a height to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by Section 1101.12.1. The secondary roof drains shall connect to a piping system in accordance with Section 1101.12.2.2.1 or Section 1101.12.2.2.2.

  1101.12.2.2.1 Separate Piping System. The secondary roof drainage system shall be a

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  STORM DRAINAGE

  separate system of piping, independent of the primary roof drainage system. The discharge shall be above grade, in a location observable by the building occupants or maintenance personnel. Secondary roof drain systems shall be sized in accordance with Section 1101.12.1

  based on the rainfall rate for which the primary system is sized. 1101.12.2.2.2 Combined System. The secondary roof drains shall connect to the vertical piping of the primary storm drainage conductor downstream of the last horizontal offset located below the roof. The primary storm drainage system shall connect to the building storm water that connects to an underground public storm sewer. The combined secondary and primary roof drain systems shall be sized in accordance with Section 1103.0 based on double the rain fall rate for the local area.

  1101.13 Cleanouts. Cleanouts for building storm drains shall comply with the requirements of Section 719.0 of this code.

  1101.13.1 Rain Leaders and Conductors. Rain leaders and conductors connected to a building storm sewer shall have a cleanout installed at the base of the

  leader or conductor before it connects to the horizontal

  drain.

  1101.14 Rainwater Sumps. Rainwater sumps serving “public use” occupancy buildings shall be provided with dual pumps arranged to function alternately in the case of overload or mechanical failure. Pumps rated 600 V or less shall comply with UL 778 and shall be installed in accordance with the manufacturer’s installation instructions.

  1101.15 Traps on Storm Drains and Leaders. Leaders and storm drains, where connected to a combined sewer, shall be trapped. Floor and area drains connected to a storm drain shall be trapped.

  Exception: Traps shall not be required where roof drains, rain leaders, and other inlets are at locations permitted under Section 906.0, Vent Termination.

  1101.15.1 Where Not Required. No trap shall be required for leaders or conductors that are connected to a sewer carrying storm water exclusively. 1101.15.2 Trap Size. Traps, where installed for individual conductors, shall be the same size as the horizontal drain to which they are connected.

  1101.15.3 Method of Installation of Combined Sewer. Individual storm-water traps shall be installed on the stormwater drain branch serving each storm-water inlet, or a single trap shall be installed in the main storm drain just before its connection with the combined building sewer. Such traps shall be provided with an accessible cleanout on the outlet side of the trap.

• 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 § 1101.1 Medium relevance — show source text

  1101.1 Applicability . . . . . . . . . . . . . . . . . .205

  1101.2 Where Required . . . . . . . . . . . . . .205

  1101.3 Storm Water Drainage to Sanitary Sewer Prohibited . . . . . .205

  1101.4 Material Uses . . . . . . . . . . . . . . . .205

  Table 1101.4.6 Materials for Subsoil Drainpipe and Fittings . . . . . . . . . . . . . . . . . .205

  1101.5 Expansion Joints Required . . . . . .205

  1101.6 Subsoil Drains . . . . . . . . . . . . . . .205

  1101.7 Building Subdrains . . . . . . . . . . . .206

  1101.8 Areaway Drains . . . . . . . . . . . . . .206

  1101.9 Window Areaway Drains . . . . . . .206

  1101.10 Filling Stations and Motor Vehicle Washing Establishments . . . . . . . . . . . . . . .206

  1101.11 Paved Areas . . . . . . . . . . . . . . . . .206

  1101.12 Roof Drainage . . . . . . . . . . . . . . .206

  1101.13 Cleanouts . . . . . . . . . . . . . . . . . . .207

  1101.14 Rainwater Sumps . . . . . . . . . . . . .207

  1101.15 Traps on Storm Drains and Leaders . . . . . . . . . . . . . . . . . . . . .207

  1101.16 Leaders, Conductors, and

  Connections . . . . . . . . . . . . . . . . .207

  1102.0 Roof Drains . . . . . . . . . . . . . . . . . .207

  1102.1 Applications . . . . . . . . . . . . . . . . .207

  1102.2 Dome Strainers Required . . . . . . .207

  1102.3 Roof Drain Flashings . . . . . . . . . .207

  1103.0 Size of Leaders, Conductors,

  and Storm Drains . . . . . . . . . . . . .207

  1103.1 Vertical Conductors and

  Leaders . . . . . . . . . . . . . . . . . . . . .207

  1103.2 Size of Horizontal Storm

  Drains and Sewers . . . . . . . . . . . .207

  1103.3 Size of Roof Gutters . . . . . . . . . . .207

  1103.4 Side Walls Draining onto a Roof . . . . . . . . . . . . . . . . . .207

  Table 1103.1 Sizing Roof Drains, Leaders, and Vertical Rainwater Piping . . .208

  1104.0 Values for Continuous Flow . . . . .208

  1104.1 General . . . . . . . . . . . . . . . . . . . . .208

  1105.0 Controlled-Flow Roof

  Drainage . . . . . . . . . . . . . . . . . . . .208

• CRC § 710.2 Medium 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 § 710.8 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 § 1506.0. Medium relevance — show source text

  site treated nonpotable gray water systems in Section

  1506.0.

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

  exclusively for subsurface landscape irrigation.

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

  1602.7.3 Storage Tanks. Rainwater storage tanks shall

  intended to collect rainwater without prior approval from

  comply with Section 1603.5.

  the Authority Having Jurisdiction.

  1602.8 Rainwater Catchment System Color and

  1603.4 Minimum Water Quality. The minimum water

  Marking Information. Rainwater catchment systems shall

  quality for harvested rainwater shall meet the applicable water

  have a colored background in accordance with Section 601.3.

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

  mined by the Authority Having Jurisdiction. In the absence of

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

  ing Jurisdiction, the minimum treatment and water quality

  1602.9 Deactivation and Drainage for Cross-Connec- shall be in accordance with Table 1603.4, IAPMO IGC 324 tion Test. The rainwater catchment system and the potable or NSF/ANSI 350. water system within the building shall be provided with the Exception [BSC] : No treatment is required for rainwater required appurtenances (e.g., valves, air or vacuum relief used for subsurface or nonsprinkled surface irrigation where valves, etc.) to allow for deactivation or drainage as required for the maximum storage volume is less than 5000 gallons (18 a cross-connection test in accordance with Section 1605.3. 927 L) where the tank is supported directly upon grade and the

  ratio of height to diameter or width does not exceed 2 to 1 .

  1603.0 Design and Installation. 1603.4.1 Disinfection. Where the initial quality of the

  collected rainwater requires disinfection or other treat-

  1603.1 Rainwater Catchment Systems. The design and

  ment or both, the collected rainwater shall be treated as

  installation of nonpotable rainwater catchment systems shall

  necessary to ensure the required water quality is deliv-

  be in accordance with Section 1603.2 through Section 1603.20.

  ered at the point of use. Where chlorine is used for dis-

  1603.2 Outside Hose Bibbs. Outside hose bibbs shall be infection or treatment, water shall be tested for residual allowed on rainwater piping systems. Hose bibbs supplying chlorine in accordance with ASTM D1253. The levels of rainwater shall be marked with the words: “CAUTION: residual chlorine shall not exceed the levels allowed for NONPOTABLE RAINWATER, DO NOT DRINK” and in the intended use in accordance with the requirements of Figure 1603.2. the local enforcing agency.

• 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 § 710.5 Medium 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 § 1701.1 Medium relevance — show source text

  Chapter 16 Nonpotable Rainwater Catchment Systems.

  Chapter 16 regulates nonpotable rainwater catchment systems that include irrigation; toilet and urinal flushing with proper treatment; provisions where permits are required; maintenance of alternate water sources; and minimum water quality. This chapter provides guidance on how to optimize rainwater use while ensuring there is a decrease of risk to consumers from poor design, installation, and maintenance. Rainwater harvesting is the process of capturing, channeling, and storing water runoff for later use. Most systems are constructed of three principal components: the catchment area, the collection device, and the conveyance system.

  Chapter 17 Referenced Standards.

  Chapter 17 provides two comprehensive tables with referenced standards. The standards listed in Table 1701.1 are applied as indicated in the applicable reference section(s). A list of additional approved standards, publications, practices, and guides that are not referenced in specific sections appear in Table 1701.2.

  Referenced standards set forth specific details of accepted practices, materials specifications, or test methods in many specialized applications. Standards provide an efficient method of conveying complex information and specifications on the performance requirements for materials, products, systems, application, and installation. The manner and purpose for a standard’s use and, in turn, code compliance, must be definitive in all references to the standard. If the standard is intended to be a requirement for judging code compliance, the code must state its intent for use. The standard should adequately address a defined need and at the same time specify the minimum performance requirements, technical characteristics and methods of testing, and required test results.

  The referenced standards tables are organized in a manner that makes it easy to find specific standards in alphabetical order, and by acronym of the publishing agency of the standard. The tables list the title of the standard, the edition, and any addenda. Contact information for each publishing agency is provided at the end of the chapter.

  Appendix A Recommended Rules for Sizing the Water Supply System.

  Appendix A provides a method of sizing the water supply and distribution system that provides precise calculations to establish the proper pressures and flow to the system’s fixtures. The goal of sizing the system is to deliver an acceptable volume of water to the most hydraulically remote fixture during minimum pressure and maximum flow conditions; provide satisfactory water pressure to the most hydraulically remote fixture during minimum pressure and maximum flow conditions; and to prevent excessive water velocity during maximum flow conditions.

  Appendix B Explanatory Notes on Combination Waste and Vent Systems.

  Appendix B contains general guidelines for the design and installation of combination waste and vent systems. These systems are designed for waste piping and are purposely oversized to serve as both a waste and vent pipe to avoid excessive pneumatic effects at fixture drains.

  Appendix C Alternate Plumbing Systems.

  The intent of this appendix is to provide clarification of procedures for the design and approval of engineered plumbing systems, alternate materials, and equipment that are not specifically covered in other parts of the code. Alternative methods are allowed to be used where approved by the authority having jurisdiction. Approval of alternatives is based on a demonstration showing that the method or material used is at least equivalent in strength, deflection, and capacity to that provided by the prescriptive methods and materials.

  Appendix D Sizing Storm Water Drainage Systems.

  Appendix D provides general guidelines for the sizing of stormwater drainage systems. There are two pieces of information that must always be a given. They are the roof size and the rate of rainfall f

• CRC § 1101.7 Medium relevance — show source text

  (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.

  1101.9 Window Areaway Drains. Window areaways at a maximum of 10 square feet (0.93 m [2] ) in area shall be permitted to discharge to the subsoil drains through a 2 inch (50 mm) diameter pipe. However, window areaways exceeding 10 square feet (0.93 m [2] ) in area shall be handled in the manner provided for entrance areaways (see Section 1101.8). 1101.10 Filling Stations and Motor Vehicle Washing Establishments. Public filling stations and motor vehicle washing establishments shall have the paved area sloped toward sumps or gratings within the property lines. Curbs not less than 6 inches (152 mm) high shall be placed where required to direct water to gratings or sumps.

  1101.11 Paved Areas. Where the occupant creates surface water drainage, the sumps, gratings, or floor drains shall be piped to a storm drain or an approved water course. 1101.12 Roof Drainage. Roof drainage shall comply with Section 1101.12.1 and Section 1101.12.2.

  1101.12.1 Primary Roof Drainage. Roof areas of a building shall be drained by roof drains or gutters. The location and sizing of drains and gutters shall be coordinated with the structural design and pitch of the roof. Unless otherwise required by the Authority Having Jurisdiction, roof drains, gutters, vertical conductors or leaders, and horizontal storm drains for primary drainage shall be sized based on a storm of 60 minutes duration and 100 year return period. Refer to Table D 101.1 (in Appendix D) for 100 years, 60-minute storms at various locations. 1101.12.2 Secondary Drainage. Secondary (emergency) roof drainage shall be provided by one of the methods specified in Section 1101.12.2.1 or Section 1101.12.2.2.

• CRC § 710.11 Medium relevance — show source text

  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.

  710.13.1 Sumps. The sump shall be watertight and gastight. 710.13.2 Discharge Piping. The discharge piping shall be sized in accordance with manufacturer’s instructions and shall be not less than [3] ⁄ 4 of an inch (20 mm) in diameter. The developed length of the discharge piping shall not exceed the manufacturer’s instructions. A check

  174 2025 CALIFORNIA PLUMBING CODE

  ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

  SANITARY DRAINAGE

  valve and fullway-type shutoff valve shall be located within the discharge line or internally within the device.

  710.13.3 Venting. The plumbing fixtures that discharge into the macerating device shall be vented in accordance with this code. The sump shall be vented in accordance with the manufacturer’s instructions, and such vent shall be permitted to connect to the fixture venting.

  711.0 Suds Relief.

  711.1 General. Drainage connections shall not be made into a drainage piping system within 8 feet (2438 mm) of a vertical to horizontal change of direction of a stack containing suds-producing fixtures. Bathtubs, laundries, washing machine standpipes, kitchen sinks, and dishwashers shall be considered suds-producing fixtures. Where parallel vent stacks are required, they shall connect to the drainage stack at a point 8 feet (2438 mm) above the lowest point of the drainage stack.

  Exceptions:

  (1) Single-family residences.

  (2) Stacks receiving the discharge from less than three stories of plumbing fixtures.

  712.0 Testing.