How must stormwater drainage and site grading be managed during construction?

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

• CRC § 4-1 High relevance — show source text

  The state agency does not adopt sections identified by the following symbol: †.

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  4 RESIDENTIAL MANDATORY MEASURES

  DIVISION 4.1 – PLANNING AND DESIGN

  SECTION 4.101—GENERAL

  4.101.1 Scope. The provisions of this division outline planning, design and development methods that include environmentally responsible site selection, building design, building siting and development to protect, restore and enhance the environmental quality of the site and respect the integrity of adjacent properties.

  SECTION 4.102—DEFINITIONS

  4.102.1 Definitions. The following terms are defined in Chapter 2.

  FRENCH DRAIN.

  WATTLES.

  SECTION 4.103—SITE SELECTION (RESERVED)

  SECTION 4.104—SITE PRESERVATION (RESERVED)

  SECTION 4.105—DECONSTRUCTION AND REUSE OF EXISTING STRUCTURES (RESERVED)

  SECTION 4.106—SITE DEVELOPMENT

  4.106.1 General. Preservation and use of available natural resources shall be accomplished through evaluation and careful planning to minimize negative effects on the site and adjacent areas. Preservation of slopes, management of storm water drainage and erosion controls shall comply with this section.

  4.106.2 Storm water drainage and retention during construction. Projects which disturb less than one acre of soil and are not part of a larger common plan of development which in total disturbs one acre or more, shall manage storm water drainage during construction. In order to manage storm water drainage during construction, one or more of the following measures shall be implemented to prevent flooding of adjacent property, prevent erosion and retain soil runoff on the site.

  1. Retention basins of sufficient size shall be utilized to retain storm water on the site.

  2. Where storm water is conveyed to a public drainage system, collection point, gutter or similar disposal method, water shall be filtered by use of a barrier system, wattle or other method approved by the enforcing agency.

  3. Compliance with a lawfully enacted storm water management ordinance.

  Note: Refer to the State Water Resources Control Board for projects which disturb one acre or more of soil, or are part of a larger common plan of development which in total disturbs one acre or more of soil.

  (Website: https://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.html)

  4.106.3 Grading and paving. Construction plans shall indicate how the site grading or drainage system will manage all surface water flows to keep water from entering buildings. Examples of methods to manage surface water include, but are not limited to, the following:

  1. Swales

  2. Water collection and disposal systems

  3. French drains

  4. Water retention gardens

  5. Other water measures which keep surface water away from buildings and aid in groundwater recharge.

  Exception: Additions and alterations not altering the drainage path.

• CRC § 3-3 High relevance — show source text

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  Part III— Building Planning and Construction

  3 BUILDING PLANNING

  User notes:

  About this chapter: Chapter 3 contains a wide array of building planning requirements that are critical to designing a safe and usable building. This includes, but is not limited to, requirements related to general structural design, fire-resistant construction, light, ventilation, sanitation, plumbing fixture clearances, minimum room area and ceiling height, safety glazing, means of egress, automatic fire sprinkler systems, smoke and carbon monoxide alarm systems, accessibility and solar energy systems.

  SECTION R300—SITE DRAINAGE

  R300.1 Storm water drainage and retention during construction. Projects which disturb less than one acre of soil and are not part of a larger common plan of development which in total disturbs one acre or more, shall manage storm water drainage during construction in accordance with the California Green Building Standards Code, Chapter 4, Division 4.1.

  R300.2 Grading and paving. Construction plans shall indicate how the site grading or drainage system will manage all surface water flows to keep water from entering buildings in accordance with the California Green Building Standards Code, Chapter 4, Division 4.1.

  SECTION R301—DESIGN CRITERIA

  R301.1 Application. Buildings and structures, and parts thereof, shall be constructed to safely support all loads, including dead loads, live loads, roof loads, flood loads, snow loads, wind loads and seismic loads as prescribed by this code. The construction of buildings and structures in accordance with the provisions of this code shall result in a system that provides a complete load path that meets the requirements for the transfer of loads from their point of origin through the load-resisting elements to the foundation. Buildings and structures constructed as prescribed by this code are deemed to comply with the requirements of this section.

  Existing buildings housing existing protective social care homes or facilities established prior to 1972 (see Chapter 11 of the California Fire Code and the California Existing Building Code).

  R301.1.1 Alternative provisions. As an alternative to the requirements in Section R301.1, the following standards are permitted subject to the limitations of this code and the limitations therein. Where engineered design is used in conjunction with these standards, the design shall comply with the California Building Code .

  1. AWC Wood Frame Construction Manual (WFCM).
  2. AISI Standard for Cold-Formed Steel Framing—Prescriptive Method for One- and Two-Family Dwellings (AISI S230).
  3. ICC Standard on the Design and Construction of Log Structures (ICC 400).

  R301.1.1.1 Alternative provisions for limited-density owner-built rural dwellings. The purpose of this subsection is to permit alternatives that provide minimum protection of life, limb, health, property, safety and welfare of the general public and the owners and occupants of limited-density owner-built rural dwellings as defined in Chapter 2 of this code. For additional informa- tion see Chapter 1, Subchapter 1, Article 8, of Title 25, California Code of Regulations, commencing with Section 74.

• CRC § 4.106.3 High relevance — show source text

  (Website: https://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.html)

  4.106.3 Grading and paving. Construction plans shall indicate how the site grading or drainage system will manage all surface water flows to keep water from entering buildings. Examples of methods to manage surface water include, but are not limited to, the following:

  1. Swales

  2. Water collection and disposal systems

  3. French drains

  4. Water retention gardens

  5. Other water measures which keep surface water away from buildings and aid in groundwater recharge.

  Exception: Additions and alterations not altering the drainage path.

  4.106.4 Electric vehicle (EV) charging for new construction. New construction shall comply with Section 4.106.4.1 or 4.106.4.2. Electric vehicle supply equipment (EVSE) shall comply with the California Electrical Code.

  Exceptions:

  1. On a case-by-case basis, where the local enforcing agency has determined EV charging and infrastructure are not feasible based upon one or more of the following conditions: 1.1. Where there is no local utility power supply or the local utility is unable to supply adequate power.

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  RESIDENTIAL MANDATORY MEASURES

  1.2. Where there is evidence suitable to the local enforcing agency substantiating that additional local utility infrastructure design requirements, directly related to the implementation of Section 4.106.4, may adversely impact the construction cost of the project. 2. Accessory Dwelling Units (ADU) and Junior Accessory Dwelling Units (JADU) without additional parking facilities.

  4.106.4.1 New one- and two-family dwellings and townhouses with attached private garages. For each dwelling unit, install a listed raceway to accommodate a dedicated 208/240-volt branch circuit. The raceway shall not be less than trade size 1 (nominal 1-inch inside diameter). The raceway shall originate at the main service or subpanel and shall terminate into a listed cabinet, box or other enclosure in close proximity to the proposed location of an EV charger. Raceways are required to be continuous at enclosed, inaccessible or concealed areas and spaces. The service panel and/or subpanel shall provide capacity to install a 40-ampere 208/240-volt minimum dedicated branch circuit and space(s) reserved to permit installation of a branch circuit overcurrent protective device.

  Exception: A raceway is not required if a minimum 40-ampere 208/240-volt dedicated EV branch circuit is installed in close proximity to the proposed location of an EV charger at the time of original construction in accordance with the California Elec- trical Code .

  4.106.4.1.1 Identification. The service panel or subpanel circuit directory shall identify the overcurrent protective device space(s) reserved for future EV charging as “EV CAPABLE”. The raceway termination location shall be permanently and visibly marked as “EV CAPABLE”.

• CRC § 5-3 High relevance — show source text

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  NONRESIDENTIAL MANDATORY MEASURES

  f. Protection of storm drain inlets (gravel bags or catch basin inserts). g. Perimeter sediment control (perimeter silt fence, fiber rolls). h. Sediment trap or sediment basin to retain sediment on site.

  i. Stabilized construction exits.

  j. Wind erosion control. k. Other soil loss BMP’s acceptable to the enforcing agency. 2. Good housekeeping BMP’s to manage construction equipment, materials, non-stormwater discharges and wastes that should be considered for implementation as appropriate for each project include, but are not limited to, the following: a. Dewatering activities. b. Material handling and waste management. c. Building materials stockpile management. d. Management of washout areas (concrete, paints, stucco, etc.). e. Control of vehicle/equipment fueling to contractor’s staging area. f. Vehicle and equipment cleaning performed off site. g. Spill prevention and control. h. Other housekeeping BMP’s acceptable to the enforcing agency.

  5.106.2 Stormwater pollution prevention for projects that disturb one or more acres of land. Comply with all lawfully enacted stormwater discharge regulations for projects that (1) disturb one acre or more of land, or (2) disturb less than one acre of land but are part of a larger common plan of development or sale.

  Note: Projects that (1) disturb one acre or more of land, or (2) disturb less than one acre of land but are part of a larger common plan of development or sale must comply with the postconstruction requirements detailed in the applicable National Pollutant Discharge Elimination System (NPDES) General Permit for Stormwater Discharges Associated with Construction and Land Disturbance Activities issued by the State Water Resources Control Board or the Lahontan Regional Water Quality Control Board (for projects in the Lake Tahoe Hydrologic Unit).

  The NPDES permits require postconstruction runoff (post-project hydrology) to match the preconstruction runoff (pre-project hydrology) with the installation of postconstruction stormwater management measures. The NPDES permits emphasize runoff reduction through on-site stormwater use, interception, evapotranspiration and infiltration through nonstructural controls, such as Low Impact Development (LID) practices and conservation design measures. Stormwater volume that cannot be addressed using nonstructural practices is required to be captured in structural practices and be approved by the enforcing agency.

  Refer to the current applicable permits on the State Water Resources Control Board website at: www.waterboards.ca.gov/constructionstormwater. Consideration to the stormwater runoff management measures should be given during the initial design process for appropriate integration into site development.

  5.106.3 Reserved.

  5.106.4 Bicycle parking. For buildings within the authority of California Building Standards Commission as specified in Section 103, comply with Section 5.106.4.1. For buildings within the authority of the Division of the State Architect pursuant to Section 105, comply with Section 5.106.4.2.

  5.106.4.1 Bicycle parking. [BSC-CG] Comply with Sections 5.106.4.1.1 and 5.106.4.1.2; or meet the applicable local ordinance, whichever is stricter.

• CRC § 2.1 High relevance — show source text

  2||||X|||||||||||||||||||| |R325.2.1||||X|||||||||||||||||||| |R325.3||||X|||||||||||||||||||| |R325.4.1||||X|||||||||||||||||||| |R325.8||||X|||||||||||||||||||| |R325.9||||X|||||||||||||||||||| |R326||||X|||||||||||||||||||| |R327.1||||X|||||||||||||||||||| |Figure R327.1||||†|||||||||||||||||||| |R328||||X|||||||||||||||||||| |R329|||X||||||||||||||||||||| |R329.2||||X|||||||||||||||||||| |R330|||X||||||||||||||||||||| |R331|||X||||||||||||||||||||| |R332|||X||||||||||||||||||||| |R334||||X|||||||||||||||||||| |R334.1||||X|||||||||||||||||||| |R335|||X||||||||||||||||||||| |R336|||X||||||||||||||||||||| |R337 User Note|||X|X|||||||||||||||||||| |R338 - R338.4|||X||||||||||||||||||||| |R340||||X|||||||||||||||||||| |R340.1||||X||||||||||||||||||||

  The state agency does not adopt sections identified with the following symbol: † The � designation indicates that the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures subject to HCD 1.

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  Part III— Building Planning and Construction

  3 BUILDING PLANNING

  User notes:

  About this chapter: Chapter 3 contains a wide array of building planning requirements that are critical to designing a safe and usable building. This includes, but is not limited to, requirements related to general structural design, fire-resistant construction, light, ventilation, sanitation, plumbing fixture clearances, minimum room area and ceiling height, safety glazing, means of egress, automatic fire sprinkler systems, smoke and carbon monoxide alarm systems, accessibility and solar energy systems.

  SECTION R300—SITE DRAINAGE

  R300.1 Storm water drainage and retention during construction. Projects which disturb less than one acre of soil and are not part of a larger common plan of development which in total disturbs one acre or more, shall manage storm water drainage during construction in accordance with the California Green Building Standards Code, Chapter 4, Division 4.1.

  R300.2 Grading and paving. Construction plans shall indicate how the site grading or drainage system will manage all surface water flows to keep water from entering buildings in accordance with the California Green Building Standards Code, Chapter 4, Division 4.1.

  SECTION R301—DESIGN CRITERIA

• CRC § 5.105.2. High relevance — show source text

  Exception [BSC-CG, DSA-SS]: Combined addition(s) to existing building(s) of two times the area or more of the existing building(s) is not eligible to meet compliance with Section 5.105.2.

  5.105.2 Reuse of existing building. An alteration or addition to an existing building shall maintain at a minimum 45 percent combined of the existing building’s primary structural elements (foundations; columns, beams, walls, and floors; and lateral elements) and existing building enclosure (roof framing, wall framing and exterior finishes). Window assemblies, insulation, portions of buildings deemed structurally unsound or hazardous, and hazardous materials that are remediated as part of the project shall not be included in the calculation.

  5.105.2.1 Verification of compliance. Documentation shall be provided in the construction documents to demonstrate compliance with Section 5.105.2.

  Note: Sample Worksheet WS-3 in Chapter 8 may be used to assist in documenting compliance with this section.

  5.105.3 Deconstruction (Reserved).

  SECTION 5.106—SITE DEVELOPMENT

  5.106.1 Stormwater pollution prevention for projects that disturb less than one acre of land. Newly constructed projects and additions which disturb less than one acre of land and are not part of a larger common plan of development or sale shall prevent the pollution of stormwater runoff from the construction activities through one or more of the following measures:

  5.106.1.1 Local ordinance. Comply with a lawfully enacted stormwater management and/or erosion control ordinance.

  5.106.1.2 Best management practices (BMP’s). Prevent the loss of soil through wind or water erosion by implementing an effective combination of erosion and sediment control and good housekeeping BMP’s.

  1. Soil loss BMP’s that should be considered for implementation as appropriate for each project include, but are not limited to, the following: a. Scheduling construction activity during dry weather, when possible. b. Preservation of natural features, vegetation, soil and buffers around surface waters. c. Drainage swales or lined ditches to control stormwater flow. d. Mulching or hydroseeding to stabilize disturbed soils. e. Erosion control to protect slopes.

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  NONRESIDENTIAL MANDATORY MEASURES

  f. Protection of storm drain inlets (gravel bags or catch basin inserts). g. Perimeter sediment control (perimeter silt fence, fiber rolls). h. Sediment trap or sediment basin to retain sediment on site.

  i. Stabilized construction exits.

  j. Wind erosion control. k. Other soil loss BMP’s acceptable to the enforcing agency. 2. Good housekeeping BMP’s to manage construction equipment, materials, non-stormwater discharges and wastes that should be considered for implementation as appropriate for each project include, but are not limited to, the following: a. Dewatering activities. b. Material handling and waste management. c. Building materials stockpile management. d. Management of washout areas (concrete, paints, stucco, etc.). e. Control of vehicle/equipment fueling to contractor’s staging area. f. Vehicle and equipment cleaning performed off site. g. Spill prevention and control. h. Other housekeeping BMP’s acceptable to the enforcing agency.

• CRC § 4.106.2 High relevance — show source text

  4.106.2 Storm water drainage and retention during construction. Projects which disturb less than one acre of soil and are not part of a larger common plan of development which in total disturbs one acre or more, shall manage storm water drainage during construction. In order to manage storm water drainage during construction, one or more of the following measures shall be implemented to prevent flooding of adjacent property, prevent erosion and retain soil runoff on the site.

  1. Retention basins of sufficient size shall be utilized to retain storm water on the site.

  2. Where storm water is conveyed to a public drainage system, collection point, gutter or similar disposal method, water shall be filtered by use of a barrier system, wattle or other method approved by the enforcing agency.

  3. Compliance with a lawfully enacted storm water management ordinance.

  Note: Refer to the State Water Resources Control Board for projects which disturb one acre or more of soil, or are part of a larger common plan of development which in total disturbs one acre or more of soil.

  (Website: https://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.html)

  4.106.3 Grading and paving. Construction plans shall indicate how the site grading or drainage system will manage all surface water flows to keep water from entering buildings. Examples of methods to manage surface water include, but are not limited to, the following:

  1. Swales

  2. Water collection and disposal systems

  3. French drains

  4. Water retention gardens

  5. Other water measures which keep surface water away from buildings and aid in groundwater recharge.

  Exception: Additions and alterations not altering the drainage path.

  4.106.4 Electric vehicle (EV) charging for new construction. New construction shall comply with Section 4.106.4.1 or 4.106.4.2. Electric vehicle supply equipment (EVSE) shall comply with the California Electrical Code.

  Exceptions:

  1. On a case-by-case basis, where the local enforcing agency has determined EV charging and infrastructure are not feasible based upon one or more of the following conditions: 1.1. Where there is no local utility power supply or the local utility is unable to supply adequate power.

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  RESIDENTIAL MANDATORY MEASURES

  1.2. Where there is evidence suitable to the local enforcing agency substantiating that additional local utility infrastructure design requirements, directly related to the implementation of Section 4.106.4, may adversely impact the construction cost of the project. 2. Accessory Dwelling Units (ADU) and Junior Accessory Dwelling Units (JADU) without additional parking facilities.

• CRC § 101.12.2 High relevance — show source text

  S 101.12.2 Bypass Connection. A bypass shall be provided for the input connection to the stormwater treatment system. The bypass shall be a diverter valve normally open to the stormwater treatment system. The normally closed port of the diverter valve shall be connected directly to the storm drainage system or combined sewer system in accordance with this code.

  TABLE S 101.11(1)

  RISK LEVELS

  • See Section S 101.2 for other uses approved by the Authority Having Jurisdiction.

  S 101.12.3 Overflow Connection. Stormwater treatment overflow shall be connected directly to the storm drainage or combined sewer system in accordance with this code. The overflow shall be provided with a backwater valve at the point of connection to the storm drainage or combined sewer system. The backwater valve shall be accessible for inspection and maintenance.

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

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

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

  (1) General project information.

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

  (3) Processes to be tested.

  (4) Criteria or process for testing.

  (5) Criteria or process for acceptance.

  (6) Commissioning team contact information.

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

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

  TABLE S 101.11(2)

  MONITORING PARAMETERS

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  APPENDIX S

• CRC § 1101.12.2.2 High 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.

• CPC § 2025 High relevance — show source text

  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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  FORMAT OF THE UNIFORM PLUMBING CODE

  Chapter 10 Traps and Interceptors.

  Chapter 10 regulates the material, design, and installation of traps, interceptors, and separators. Traps are required on drainage type plumbing fixtures and must be self-scouring without interior partitions. Interceptors, on the other hand, are designed to control what goes down a drain. Interceptors are used to keep harmful substances from entering the sanitary drainage system, such as grease, sand, oil and other materials. The retained materials need periodic removal to maintain efficiency and function of the separating device. The capacity of an interceptor is based on retention and flow rate. There are many types of interceptors that are used at beauty salons, hospitals, meat, fish or foul packaging, refineries, repair garages, gas stations, car washing facilities, various plants, factories, and processing sites. The designer of the building is responsible for locating interceptors with the expectation for the frequency of maintenance, ease of cleaning and floor space for equipment.

  Chapter 11 Storm Drainage.

  Chapter 11 regulates the removal of stormwater from roofs, yards, paved areas, and similar areas. The objective of storm drainage systems is to provide a conduit or channel through which runoff will be carried from a point of collection to a point of disposal; this protects the property and the public from the uncontrolled flow of runoff and ensures that drains and inlets are adequately sized to receive the volume of runoff that flows to the drains. For the purpose of system design, it’s necessary to specify the duration of a selected storm.

• CRC § 1.11.0. High relevance — show source text

  Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
  Adopting Agency	BSC	BSC- CG	SFM	1	2	1-AC	AC	** SS**	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
  Adopt Entire Chapter				X
  Adopt Entire Chapter as amended (amended sections listed below)
  Adopt only those sections that are listed below
  Chapter/Section

  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 S

  ONSITE STORMWATER TREATMENT SYSTEMS

  The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

  S 101.0 Onsite Stormwater Treatment Systems. S 101.1 General. The provisions of this appendix shall apply to the water quality, monitoring, design, construction, alteration, repair, and operation requirements of onsite stormwater treatment systems for nonpotable use. S 101.2 Allowable Use of Stormwater. Where approved or required by the Authority Having Jurisdiction, stormwater shall be permitted to be used in lieu of potable water for uses such as, but not limited to, water closets, urinals, clothes washers, ornamental plant irrigation, and dust suppression. S 101.3 Design and Construction Requirements. Onsite stormwater treatment systems shall meet the design, construction, and performance requirements of Section S 101.3.1 or Section S 101.3.2.

  S 101.3.1 Listed Stormwater Treatment Systems. Onsite stormwater treatment systems shall be listed to ARCSA/ASPE 78, installed according to the manufacturer's instructions, and commissioned in accordance with Section S 101.13.

  **S 101.3.2 Alternative Design Systems.

• CRC § 1101.4 High relevance — show source text

  (Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
  Adopting Agency	BSC	BSC- CG	SFM	1	2	1-AC	AC	** SS**	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
  Adopt Entire Chapter								X			X					X
  Adopt Entire Chapter as amended (amended sections listed below)	X			X	X					X		X	X	X	X
  Adopt only those sections that are listed below
  Chapter/Section
  1101.4	X			X	X					X		X	X	X	X
  1101.4.2.1				X
  1101.4.2.2										X		X	X	X	X
  1101.6_ Exception_				X	X

  This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

  2025 CALIFORNIA PLUMBING CODE 203

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

  204 2025 CALIFORNIA PLUMBING CODE

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

  CHAPTER 11

  STORM DRAINAGE

  1101.0 General.

  1101.1 Applicability. This chapter shall govern the materials, design, and installation of storm water drainage systems. 1101.2 Where Required. Roofs, paved areas, yards, courts, courtyards, vent shafts, light wells, or similar areas having rainwater, shall be drained into a separate storm sewer system, or into a combined sewer system where a separate storm sewer system is not available, or to some other place of disposal satisfactory to the Authority Having Jurisdiction.