CWUIC · California Wildland-Urban Interface Code
Testing, maintenance and water-supply reliability (standby power)
If a water tank or pump in a wildland‑urban interface depends on electricity, the CWUIC requires periodic testing and maintenance (per **§ 404.9**) and a standby power source that can run pumps/controllers for at least **2 hours** (per **§ 404.10.3**), unless a code‑official‑approved exception applies; installation details must follow the CBC and CFC referenced by the CWUIC.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
Water supply equipment required by the CWUIC must be periodically tested and kept in operative condition, and stationary water-supply facilities that depend on electrical power must have a standby power source capable of running for not less than 2 hours. The testing/maintenance rule is in § 404.9 and the reliability/standby-power requirements are in § 404.10 and § 404.10.3.
If a pump or pump controller needs electricity to deliver the required fire water, provide a standby power source that will run it for at least two hours and keep all water-supply equipment tested and in service.
Requirements in detail
Key defined terms (first mention)
- Standby power — an alternate power source that supplies pumps, controllers and related electrical equipment when primary power is lost (see § 404.10.3).
- Defensible space — cleared area around tanks/pump houses required by § 404.10.2 (see Section 603 for details).
- Stationary water supply facilities — fixed tanks, pumps and pump houses that provide the code-required water supply (referenced in § 404.10.3).
What must be tested and maintained
- Water sources, draft sites, hydrants and other fire-protection equipment required by the CWUIC are subject to periodic tests as required by the code official and must be maintained in operative condition; defective equipment must be repaired or replaced. This is the requirement in § 404.9.
Standby power (who, what, how long, standards)
- Where stationary water supply facilities are dependent on electrical power, standby power shall be provided to pumps, controllers and related electrical equipment so the required water supply can be delivered. See § 404.10.3.
- The standby power source must be installed in accordance with Chapter 27 of the California Building Code (CBC) and Section 1203 of the California Fire Code (CFC) — the CWUIC points you to those standards for installation, connections and fire-safety requirements. See § 404.10.3.
- Minimum runtime: 2 hours — the standby source must be capable of providing power for not less than 2 hours. See § 404.10.3 and Appendix A guidance A107.5.
Clearance and fuel exposure
- Defensible space must be provided around water tanks, pumps and pump houses per § 404.10.2, which directs compliance with Section 603 for the required clearance. This reduces exposure of equipment to fire and aligns with the reliability objective in § 404.10.1.
Decision table — quick reference for inspectors/designers/owners
| Decision dimension | Requirement / value | Code reference |
|---|---|---|
| Periodic testing & maintenance | Subject to periodic tests as required by the code official; maintain in operative condition | § 404.9 |
| Applies to | Water sources, draft sites, hydrants, fire-protection equipment required by CWUIC | § 404.9 |
| Standby power required when | Stationary water supply facilities are dependent on electrical power | § 404.10.3 |
| Standby power standard(s) | Install per CBC Ch. 27 and CFC §1203 | § 404.10.3 |
| Minimum standby runtime | Not less than 2 hours | § 404.10.3, A107.5 |
| Fuel clearance around facilities | Provide defensible space around tanks/pumps/pump houses per Section 603 | § 404.10.2 |
| Exceptions to standby power | No standby required when primary power is underground (with approval) or facility serves not more than one single‑family dwelling | § 404.10.3 (Exceptions 1 & 2) |
Exceptions & special cases
- Exception 1 in § 404.10.3: a standby power supply is not required where the primary power service to the stationary water supply facility is underground, subject to approval by the code official.
- Exception 2 in § 404.10.3: a standby power supply is not required where the stationary water supply facility serves not more than one single‑family dwelling.
- The code official has discretion: periodic testing frequency and whether the underground-primary-power exception is acceptable are administratively determined under § 404.9 and § 404.10.3.
If your project relies on an exception, document the basis and get written approval from the code official; the CWUIC text requires approval for the underground‑service exception.
Common mistakes
- Assuming the 2‑hour runtime is optional — it is a minimum requirement in § 404.10.3 and Appendix guidance A107.5.
- Providing a portable or manual-start generator without automatic transfer or automatic starting of pump controllers when required by the local authority — the CWUIC points to CBC/CFC installation rules; follow those standards for required transfer switches and automatic operation (see § 404.10.3).
- Forgetting defensible space for pump houses and tanks (Section 603 referenced by § 404.10.2) — clearance is part of reliability, not optional.
- Treating the single‑family exception as applying to multi‑unit or multiple accessory structures — the code limits the exemption to facilities that serve not more than one single‑family dwelling. § 404.10.3, Exception 2.
Worked example — sizing a standby generator to meet the 2‑hour requirement
Scenario: A community water tank has a single electric pump motor rated 5 hp (continuous), and the pump controller and controls draw an additional 0.5 kW.
- Convert motor power to kW: 1 hp ≈ 0.746 kW → 5 hp ≈ 3.73 kW.
- Add controls load: 3.73 kW + 0.5 kW = 4.23 kW continuous.
- Select a generator sized above continuous load (allowing for starting surge and derating). A common practice is to allow 25–30% margin for motor starting and continuous operation: 4.23 kW × 1.3 ≈ 5.5 kW generator.
- Runtime energy for the required 2 hours: 4.23 kW × 2 h = 8.46 kWh. Ensure fuel supply and generator fuel tank or fuel type supports at least 2 hours continuous operation at expected load.
Notes: the CWUIC requires a standby source capable of providing power for at least 2 hours (see § 404.10.3 and Appendix A107.5). The CWUIC does not prescribe exact generator kW sizing or margins — those come from equipment manufacturer data and the referenced CBC/CFC/Cec installation rules that § 404.10.3 points to. Confirm automatic transfer, ventilation and fuel storage requirements per CBC Ch. 27 and CFC §1203.
Related provisions
- § 404.9 — Testing and maintenance (periodic tests, maintenance in operative condition).
- § 404.10 — Reliability (objective and cross‑references).
- § 404.10.1 — Objective: reduce exposure of fuels to electrically powered systems.
- § 404.10.2 — Clearance of fuel: defensible space around tanks/pumps (see Section 603).
- § 404.10.3 — Standby power requirements and exceptions (minimum 2 hours; CBC/CFC references).
- Appendix A A107.5 — Protection of electrical power supplies; repeats the 2‑hour guidance and references CBC/CFC/CEC for installation.
- Section 603 — Defensible space requirements referenced by § 404.10.2 (see the CWUIC chapter on vegetation/defensible space).
Code references
Grounded in the retrieved California Wildland-Urban Interface Code — click a citation to read the verbatim passage:
CWUIC § 404.9 High relevance — show source text
May_ 1988.
404.9 Testing and maintenance. Water sources, draft sites, hydrants and other fire protection equipment required by this code shall be subject to periodic tests as required by the code official. Such equipment installed under the provisions of this code shall be maintained in an operative condition at all times and shall be repaired or replaced where defective. Additions, repairs, alterations and servicing of such fire protection equipment and resources shall be in accordance with approved standards.
404.10 Reliability. Water supply reliability shall comply with Sections 404.10.1 through 404.10.3.
404.10.1 Objective. The objective of this section is to increase the reliability of water supplies by reducing the exposure of vegetative fuels to electrically powered systems.
404.10.2 Clearance of fuel. Defensible space shall be provided around water tank structures, water supply pumps and pump houses in accordance with Section 603.
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 4-7
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
WILDLAND-URBAN INTERFACE AREA REQUIREMENTS
404.10.3 Standby power. Standby power shall be provided to pumps, controllers and related electrical equipment so that stationary water supply facilities within the wildland-urban interface area that are dependent on electrical power can provide the required water supply. The standby power system shall be in accordance with Section 2702 of the California Building Code and Section 1203 of the California Fire Code . The standby power source shall be capable of providing power for not less than 2 hours.
Exceptions:
- Where approved by the code official, a standby power supply is not required where the primary power service to the stationary water supply facility is underground.
- A standby power supply is not required where the stationary water supply facility serves not more than one singlefamily dwelling.
�
4-8 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE
CHAPTER 5 – SPECIAL BUILDING CONSTRUCTION REGULATIONS
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CWUIC § 404.5 High relevance — show source text
404.5 Adequate water supply. Fire-flow requirements shall be determined in accordance with Appendix B or BB of the California Fire Code, as applicable.
404.6 Reserved.
404.7 Obstructions. Access to water sources required by this code shall be unobstructed at all times. The fire department shall not be deterred or hindered from gaining immediate access to water source equipment, fire protection equipment or hydrants.
404.8 Identification. Water sources, draft sites, hydrants and fire protection equipment and hydrants shall be clearly identified in a manner approved by the code official to identify location and to prevent obstruction by parking and other obstructions. Each fire hydrant and access to a water supply shall be identified in accordance with one of the following: 1. Where located along a driveway, a reflectorized blue marker with a minimum dimension of 3 inches (73 mm) shall be located on the driveway address sign and mounted on a fire-retardant post. 2. Where located along an access road: 2.2. A reflectorized blue marker with a minimum dimension of 3 inches (73 mm) shall be mounted on a fire-retardant post. The signpost shall be within 3 feet (914 mm) of said fire hydrant with the sign not less than 3 feet (914 mm) nor greater than 5 feet (1524 mm) above ground, in a horizontal position and visible from the driveway. 2.3. As specified in the State Fire Marshal’s Guidelines for Fire Hydrant Markings Along State Highways and Freeways, May 1988.
404.9 Testing and maintenance. Water sources, draft sites, hydrants and other fire protection equipment required by this code shall be subject to periodic tests as required by the code official. Such equipment installed under the provisions of this code shall be maintained in an operative condition at all times and shall be repaired or replaced where defective. Additions, repairs, alterations and servicing of such fire protection equipment and resources shall be in accordance with approved standards.
404.10 Reliability. Water supply reliability shall comply with Sections 404.10.1 through 404.10.3.
404.10.1 Objective. The objective of this section is to increase the reliability of water supplies by reducing the exposure of vegetative fuels to electrically powered systems.
404.10.2 Clearance of fuel. Defensible space shall be provided around water tank structures, water supply pumps and pump houses in accordance with Section 603.
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 4-7
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
WILDLAND-URBAN INTERFACE AREA REQUIREMENTS
404.10.3 Standby power. Standby power shall be provided to pumps, controllers and related electrical equipment so that stationary water supply facilities within the wildland-urban interface area that are dependent on electrical power can provide the required water supply. The standby power system shall be in accordance with Section 2702 of the California Building Code and Section 1203 of the California Fire Code . The standby power source shall be capable of providing power for not less than 2 hours.
CWUIC § 404.10.2 High relevance — show source text
404.10.2 Clearance of fuel. Defensible space shall be provided around water tank structures, water supply pumps and pump houses in accordance with Section 603.
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 4-7
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
WILDLAND-URBAN INTERFACE AREA REQUIREMENTS
404.10.3 Standby power. Standby power shall be provided to pumps, controllers and related electrical equipment so that stationary water supply facilities within the wildland-urban interface area that are dependent on electrical power can provide the required water supply. The standby power system shall be in accordance with Section 2702 of the California Building Code and Section 1203 of the California Fire Code . The standby power source shall be capable of providing power for not less than 2 hours.
Exceptions:
- Where approved by the code official, a standby power supply is not required where the primary power service to the stationary water supply facility is underground.
- A standby power supply is not required where the stationary water supply facility serves not more than one singlefamily dwelling.
�
4-8 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE
CHAPTER 5 – SPECIAL BUILDING CONSTRUCTION REGULATIONS
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM Col5 HCD Col7 Col8 DSA Col10 OSHPD Col12 Col13 Col14 Col15 Col16 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGT-24 T-19* 1 2 1/AC AC SS 1 1R 2 3 4 5 5 5 5 5 5 5 5 5 Adopt Entire Chapter Adopt Entire Chapter as
amended (amended sections
listed below)X Adopt only those sections that
are listed below[California Code of Regulations,
Title 19, Division 1]Chapter / Section 501.1 X 501.2 X 501.4 – 501.4.1 X 502_Reserved_ X 503.1 X 503. CWUIC § 1203 High relevance — show source text
A107.5 Protection of electrical power supplies. Where electrical pumps are used to provide the required water supply, such pumps shall be connected to a standby power source to automatically maintain electrical power in the event of power loss. The standby power source shall be capable of providing power for not less than 2 hours in accordance with Chapter 27 of the California Building Code, Section 1203 of the California Fire Code and the California Electrical Code.
Exception: A standby power source is not required where the primary power service to pumps is underground as approved by the code official.
SECTION A108—LAND USE LIMITATIONS
A108.1 General. Temporary fairs, carnivals, public exhibitions and similar uses must comply with all other provisions of this code in addition to enhanced ingress and egress requirements.
A108.2 Objective. The increased public use of land or structures in wildland-urban interface areas increases the potential threat to life safety. The provisions of this section are intended to reduce that threat.
A108.3 Permits. Temporary fairs, carnivals, public exhibitions or similar uses shall not be allowed in a designated wildland-urban interface area, except by permit from the code official.
Permits shall incorporate such terms and conditions that will reasonably safeguard public safety and property.
A108.4 Access roadways. In addition to the requirements in Section 403, access roadways shall be not less than 24 feet (7315 mm) wide and posted NO PARKING. Two access roadways shall be provided to serve the permitted use area.
Where required by the code official to facilitate emergency operations, approved emergency vehicle operating areas shall be provided.
APPENDIX A-6 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX A—GENERAL REQUIREMENTS
SECTION A109—REFERENCED STANDARDS
A109.1 General. See Table A109.1 for standards that are referenced in various sections of this appendix. Standards are listed by the standard identification with the effective date, standard title and the section or sections of this appendix that reference the standard.
TABLE A109.1—REFERENCED STANDARDS Col2 Col3 STANDARD ACRONYM STANDARD NAME SECTIONS HEREIN REFERENCED CBC—25 California Building Code A107.5 CFC—25 California Fire Code A104.6, A105.1, A107.5 CEC—25 California Electrical Code A107.5 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE APPENDIX A-7
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX A-8 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CALIFORNIA WILDLAND-URBAN INTERFACE CODE – MATRIX ADOPTION TABLE
APPENDIX B – VEGETATION MANAGEMENT PLAN
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
(Not adopted by the State Fire Marshal)
CWUIC § 1.5 High relevance — show source text
Division 1.5
Section|Title 19,
Division 1
Section|Gov Code
Section|PRC
Section|HSC
Section| |---|---|---|---|---|---|---|---|---|---|---| |Section|Title|Title|Title|Title|Title|Title|Title|Title|Title|Title| |Chapter 4|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements| |403.2.5|Address installation,
location, and visibility|Y||||1274.04(a)
1274.04(b)
1274.04(c)
1274.04(d)
1274.04(e)
1274.04(f)||||| |404|Water supply|Y||||1275.02||||| |404.1|General|Y|||507|1275.02(b)||||| |404.2|Required water supply|Y||||1275.02(c)||||| |404.3|Draft sites|Y||||||||| |404.3.1|Access|Y|||507.5.4|||||| |404.3.2|Pumper access points|Y|404.3.2|||||||| |404.4|Hydrants|Y|||507.5|||||| |404.5|Adequate water
supply|Y|||507.3|1275.02(b)||||| |404.6|Reserved|N||||||||| |404.7|Obstructions|Y|||507.5.4|||||| |404.8|Identification|Y||||1275.04(a)||||| |404.9|Testing and
maintenance|Y|||507.5.2|||||| |404.10|Reliability|Y|||507.5.2|||||| |404.10.1|Objective|Y|404.10.1|||||||| |404.10.2|Clearance of fuel|Y|||4907.1|||||| |404.10.3|Standby power|Y|||507.5.2|||||| |Chapter 5|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations| |501|General|Y||701A||||||| |501.1|Scope|Y||701A.3||||||| |501.2|Objective|Y||701A.2||||||| |501.3|Fire-resistance-rated
construction|Y||703.2.1.5||||||| |501.4|Noncombustibility
tests|Y||703.3||||||| |501.4.1|Noncombustible
materials|Y||703.3.CWUIC § 104.2.2.7 Medium relevance — show source text
Outbuilding 202
Peer Review 104.2.2.7, 202 Permits
Application 105.4 Approval 105.5 Expiration 105.8 Issuance 105.6 Preliminary inspection 105.4.1 Refusal to issue 105.6.1
Required 105.2 Retention 105.9
Revocation 105.10 Validity 105.7 Work exempt from permit 105.3 Placarding as Unsafe 109.3.5.3 Powers and Duties of the Code
Official 104.1
Practical Difficulties 104.2.3 Protection of Pumps and Water Storage Facilities Appendix A, A107
Rafter Tail 202 Referenced Standards 102.4, Chapter 7 Registered Design Professional 104.2.1.2, 104.2.2.6.2, 106.1, 202 Residential Unit 202 Retroactivity 101.4 Ridgelline 202 Road 202 Roof Covering 202 Roof Covering System 202 Roof Coverings, Replacement or Repair of 507
Roof Deck 202
Scope 101 Self-Defense Mechanism Appendix G Service Utilities 111
Slope 202 Spark Arrestors 605 Stop Work Order 113 Storage of Firewood and Combustible Materials 607 Strategic Ridgeline 202 Structure 202
Subdivision 202
Technical Assistance 104.2.1 Temporary Uses, Equipment and Systems 107 Tree Crown 202
Trees 603.4.2
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE INDEX-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
INDEX
Undeveloped Ridgeline 202 Unenclosed Accessory Structure 202
Vegetation Control Appendix A, A102 Vegetation management compliance 106.4 Vegetation Management Plan Appendix B Vents 504.10
Vertical Curve 202
Water Supply Adequate water supply 404.5 Applicability 402 Draft sites 404.3 Hydrants 404.4 Identification 404.8
Obstructions 404.7 Reliability 404.10 Required water supply 404.2 Subdivisions 402.1 Testing and maintenance 404.9 Water sources 404.2
Wildfire 202
Wildland 202
Wildland-Urban Interface Area 202
Wildland-Urban Interface Area Designations 302 Declaration 302.1
Mapping 302.2 Review 302.3
INDEX-2 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
HISTORY NOTE APPENDIX
2025 California Wildland-Urban Interface Code California Code of Regulations, Title 24, Part 7
HISTORY:
California Wildland-Urban Interface Code Medium relevance — show source text
159
252
316
354
384
440|7420
4734
4701
4647
4594
4542
4442|3770
3050
3020
2970
2920
2870
2785|0
199
312
386
431
467
540|9341
5900
5863
5803
5744
5686
5574|4750
3810
3783
3739
3695
3650
3565|0
241
373
456
507
548
635|11 483
7194
7155
7090
7026
6964
6842|5850
4650
4622
4574
4527
4480
4375|0
285
439
535
590
639
739|13 848
8617
8574
8505
8437
8370
8239|7060
5600
5552
5471
5391
5310
5225| |50|0
2
5
10
15
20
30|0
113
191
243
274
300
347|6711
4554
4520
4464
4409
4356
4253|3440
2840
2813
2767
2721
2675
2631|0
141
234
295
330
361
412|8774
5864
5826
5763
5701
5641
5523|4460
3670
3639
3585
3534
3481
3431|0
171
283
355
396
433
494|11 129
7339
7295
7224
7155
7086
6953|5635
4630
4597
4542
4511
4479
4421|0
209
336
419
465
506
577|13 767
8980
8933
8855
8779
8704
8557|6940
5695
5654
5585
5546
5506
5444|0
251
394
491
542
586
672|16 694
10 788
10 737
10 652
10 570
10 488
10 328|8430
6860
6818
6749
6710
6670
6603| |100|0
2
5
10
15
20
30
50|0CWUIC § 3.2 Medium relevance — show source text
3.2|||||||| |404.4|Hydrants|Y|||507.5|||||| |404.5|Adequate water
supply|Y|||507.3|1275.02(b)||||| |404.6|Reserved|N||||||||| |404.7|Obstructions|Y|||507.5.4|||||| |404.8|Identification|Y||||1275.04(a)||||| |404.9|Testing and
maintenance|Y|||507.5.2|||||| |404.10|Reliability|Y|||507.5.2|||||| |404.10.1|Objective|Y|404.10.1|||||||| |404.10.2|Clearance of fuel|Y|||4907.1|||||| |404.10.3|Standby power|Y|||507.5.2|||||| |Chapter 5|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations| |501|General|Y||701A||||||| |501.1|Scope|Y||701A.3||||||| |501.2|Objective|Y||701A.2||||||| |501.3|Fire-resistance-rated
construction|Y||703.2.1.5||||||| |501.4|Noncombustibility
tests|Y||703.3||||||| |501.4.1|Noncombustible
materials|Y||703.3.1||||||| |502|RESERVED|N||||||||| |503|Ignition-resistant
construction and
material|Y||704A||||||| |503.1|General|Y||701A.3||||||| |503.2|Ignition-resistant
building material|Y||707A.3 #2||||||| |503.2.1|Noncombustible
material|Y||704A.4 #1||||||| |503.2.2|Fire-retardant-
treated wood|Y||704A.4 #2||||||| |503.2.3|Fire-retardant-
treated wood roof
coverings|Y||705A.1||||||| |503.2.4|Other ignition-
resistant building
material|Y||704A.3||||||| |503.2.4.1|Flame spread|Y||704A.3 #1||||||| |503.2.4.2|Flame front|Y||704A.3 #2||||||| |503.2.4.3|Weathering|Y||703A.5.1||||||| |503.2.4.3.1|Evaluation require-
ments for weathering|Y||703A.5.2
703A.5.2.1||||||| |503.2.4.3.2|Wood-plastic
composite materials|Y||703A.6|||||||APPENDIX H-28 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS
CWUIC § 603.4.2 Medium relevance — show source text
Trees 603.4.2
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE INDEX-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
INDEX
Undeveloped Ridgeline 202 Unenclosed Accessory Structure 202
Vegetation Control Appendix A, A102 Vegetation management compliance 106.4 Vegetation Management Plan Appendix B Vents 504.10
Vertical Curve 202
Water Supply Adequate water supply 404.5 Applicability 402 Draft sites 404.3 Hydrants 404.4 Identification 404.8
Obstructions 404.7 Reliability 404.10 Required water supply 404.2 Subdivisions 402.1 Testing and maintenance 404.9 Water sources 404.2
Wildfire 202
Wildland 202
Wildland-Urban Interface Area 202
Wildland-Urban Interface Area Designations 302 Declaration 302.1
Mapping 302.2 Review 302.3
INDEX-2 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
HISTORY NOTE APPENDIX
2025 California Wildland-Urban Interface Code California Code of Regulations, Title 24, Part 7
HISTORY:
- (SFM 08/24)—Adoption by reference of the 2024 International Wildland-Urban Interface Code with necessary amendments relocated from the California Building Code, California Residential Code and California Fire Code to become the 2025 Califor- nia Wildland-Urban Interface Code . Approved by the California Building Standards Commission on February 26, 2025, filed with Secretary of State on March 7, 2025, and effective on January 1, 2026.
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE HIST-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
HIST-2 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
Go Digital, Work Smarter with Premium Complete
Get access to exclusive tools, features, and
over 2,000 codes and standards.
25-24572
Activate your FREE 14-day trial. No Credit Card required! codes.iccsafe.org
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CWUIC § A107 Medium relevance — show source text
Exception: Approved public and approved private dumping areas.
A106.2 Ashes and coals. Ashes and coals shall not be placed, deposited or dumped in or on wildland-urban interface areas.
Exceptions:
- In the hearth of an established fire pit, camp stove or fireplace.
- In a noncombustible container with a tightfitting lid, which is kept or maintained in a safe location not less than 10 feet (3048 mm) from nonfire-smart vegetation or structures.
- Where such ashes or coals are buried and covered with 1 foot (305 mm) of mineral earth not less than 25 feet (7620 mm) from nonfire-smart vegetation or structures.
SECTION A107—PROTECTION OF PUMPS AND WATER STORAGE FACILITIES
A107.1 General. The reliability of the water supply shall be in accordance with Sections A107.2 through A107.5.
A107.2 Objective. The intent of this section is to increase the reliability of water storage and pumping facilities and to protect such systems against loss from intrusion by fire.
A107.3 Fuel modification area. Water storage and pumping facilities shall be provided with a defensible space of not less than 30 feet (9144 mm) clear of nonfire-resistive vegetation or growth around and adjacent to such facilities.
Persons owning, controlling, operating or maintaining water storage and pumping systems requiring this defensible space are responsible for clearing and removing nonfire-smart vegetation and maintaining the defensible space on the property owned, leased or controlled by said person.
A107.4 Trees. Portions of trees that extend to within 30 feet (9144 mm) of combustible portions of water storage and pumping facilities shall be removed.
A107.5 Protection of electrical power supplies. Where electrical pumps are used to provide the required water supply, such pumps shall be connected to a standby power source to automatically maintain electrical power in the event of power loss. The standby power source shall be capable of providing power for not less than 2 hours in accordance with Chapter 27 of the California Building Code, Section 1203 of the California Fire Code and the California Electrical Code.
Exception: A standby power source is not required where the primary power service to pumps is underground as approved by the code official.
SECTION A108—LAND USE LIMITATIONS
A108.1 General. Temporary fairs, carnivals, public exhibitions and similar uses must comply with all other provisions of this code in addition to enhanced ingress and egress requirements.
A108.2 Objective. The increased public use of land or structures in wildland-urban interface areas increases the potential threat to life safety. The provisions of this section are intended to reduce that threat.
A108.3 Permits. Temporary fairs, carnivals, public exhibitions or similar uses shall not be allowed in a designated wildland-urban interface area, except by permit from the code official.
Permits shall incorporate such terms and conditions that will reasonably safeguard public safety and property.
A108.4 Access roadways. In addition to the requirements in Section 403, access roadways shall be not less than 24 feet (7315 mm) wide and posted NO PARKING. Two access roadways shall be provided to serve the permitted use area.
Where required by the code official to facilitate emergency operations, approved emergency vehicle operating areas shall be provided.
APPENDIX A-6 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
CWUIC § 3-3 Medium relevance — show source text
301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3
302 Wildland-Urban Interface Area Designations . . . . . .3-3
CHAPTER 4 WILDLAND-URBAN INTERFACE AREA
REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . 4-3
401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
402 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
403 Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
404 Water Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7
CHAPTER 5 SPECIAL BUILDING CONSTRUCTION
REGULATIONS . . . . . . . . . . . . . . . . . . . . . . . . 5-3
501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3
502 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3
503 Ignition-Resistant Construction and Material. . . . . .5-3
504 Ignition-Resistant Construction. . . . . . . . . . . . . . . . . .5-4
505 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-9
506 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-9
507 Replacement or Repair of Roof Coverings. . . . . . . . .5-9
CHAPTER 6 FIRE PROTECTION REQUIREMENTS. . . . . . .6-3
601 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
602 Fire Protection Plans . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
603 Vegetation Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
604 Maintenance of Defensible Space . . . . . . . . . . . . . . . 6-5
Frequently asked questions
Who decides how often hydrants and pumps must be tested?
The code official sets the periodic testing frequency under § 404.9; the code requires testing as the official determines.
Is the 2‑hour standby runtime a hard minimum?
Yes — the standby power source must be capable of providing power for not less than 2 hours per § 404.10.3 and Appendix A107.5.
Can I avoid a generator if the utility service is underground?
Possibly — Exception 1 of § 404.10.3 says the code official may approve not requiring standby power where the primary power service is underground. Get written approval from the authority having jurisdiction.
Does the CWUIC specify generator installation details (transfer switches, fuel tanks)?
No — CWUIC requires the standby power system to be installed in accordance with CBC Chapter 27 and CFC Section 1203; follow those referenced codes for the detailed installation, transfer switch, fuel and fire-safety requirements. § 404.10.3 directs you to those standards.
Are single‑family homes always exempt from standby power?
Not automatically — § 404.10.3 Exception 2 exempts stationary water supply facilities that serve not more than one single‑family dwelling, but site specifics and code official interpretation still apply.
More in California Wildland-Urban Interface Code
- Administration and Definitions
- Board of Appeals, Administration & Enforcement (permits, code official duties, appeals process)
- Wildland‑Urban Interface Area Designation & Mapping
- Fire Service Access & Water Supply (fire apparatus roads, driveways, hydrants, draft sites, standby power)
- Wildland‑Urban Interface Area Requirements (access, water, premises identification, key boxes)
- Referenced Standards & Test Methods
- Special Building Construction Regulations (ignition‑resistant construction, roof/vent/assembly requirements)
- Appendices and Model Ordinances (vegetation plans, severity‑zone adoption, home‑hardening guidance)
- Fire Protection Requirements (fire protection plans, systems, safety element provisions)
- Referenced California Documents & Matrix (CCR/Title 14 & 19 cross‑references, statutory references)
- Vegetation Management & Defensible Space (vegetation plans, maintenance, fire‑smart characteristics)
Ask about the CWUIC
Get cited, plain-English answers on the California Wildland-Urban Interface Code for your project — any code section, any scenario.
Start Free Trial