Utility-caused wildfires
Utility-caused wildfires are a subset of human-caused wildfires that are directly ignited by utilities, usually power lines. They are unplanned ignitions that can cause wild burns.[1] Hotter and drier weather as a result of climate change has been liked to lower moisture content in vegetation, which, along with high tree mortality has created ideal wildfire conditions.[2] Ignition often occurs when power lines come in contact with vegetation, whether elevated or on the ground.[1]
Industry critics claim that the industry is not doing enough to mitigate these disasters.[3]
Examples
[edit]Throughout the world, utilities, especially overhead power lines, have caused many wildfires.[4]
| Name | Date/Year | Location | Causes | Impact |
|---|---|---|---|---|
| Black Saturday Fires | February 7, 2009 | Victoria, Australia | High winds damaged power lines, causing electrical arcing that ignited dry vegetation. | 173 Fatalities, more than 450,000 hectares (1.1 million acres) burned, 3,500 buildings destroyed.[5][6] |
| Thomas Fire | December 4, 2017 | Ventura & Santa Barbara Counties, California, United States | High winds caused power lines to come in contact, producing sparks that ignited fuel below. | 1 Civilian fatality, 1 firefighter fatality, 281,000 acres burned, 1,063 buildings destroyed.[7] |
| Camp Fire | November 8, 2018 | Butte County, California, United States | A failed PG&E transmission tower C-hook broke causing a power line to fall and ignite dry brush. | 85 Fatalities, 153,000 acres burned, 18,800 buildings destroyed.[8][9] |
| Kincade Fire | October 23, 2019 | Sonoma County, California, United States | A broker jumper cable on a PG&E transmission tower broke, producing sparks, igniting dry vegetation. | 77,700 acres burned, 374 buildings destroyed.[10] |
| Zogg Fire | September 27, 2020 | Shasta & Tehama Counties, California, United States | A dead Gray Pine fell onto PG&E transmission lines, igniting dry vegetation below. | 4 Fatalities, 56,300 acres burned, 204 buildings destroyed.[11] |
| Dixie Fire | July 13, 2021 | Northern California, United States | A Douglas fir fell onto PG&E distribution power line, igniting dry vegetation. | 1 Firefighter fatality, 963,300 acres, 1,329 buildings destroyed.[12] |
| Lahaina Fire | August 8, 2023 | Maui, Hawaii, United States | Broken powerlines created sparks ignited unmaintained vegetation due. | 102 Fatalities, 2,170 acres burned, 2,170 buildings destroyed.[13][14][15] |
| Smokehouse Creek Fire | February 26, 2024 | Texas Panhandle & Oklahoma, United States | A decayed utility pole fell on dry grass and ignited the grass. | 2 Fatalities, 428,300 hectares (1 million acres) burned, Over 500 buildings destroyed.[16][17] |
| Attica Wildfires | August 11, 2024 | Attica, Greece | A loose electrical cable on a damaged wooden utility pole failed and sparked a fire beneath the line. | 1 Fatality, 10,000 hectares (24,700 acres) burned.[18] |
| Highway 82 Fire (Active Fire) | April 20, 2026 | Brantley, Wayne, & Glynn Counties, Georgia, United States | A Mylar balloon contacted a power line, causing electrical arcing that ignited vegetation below. | Over 22,000 acres burned, Over 100 buildings destroyed.[19] |
Causes
[edit]Utility-cased wildfires can be started by a variety of factors.
Downed lines
[edit]The vast majority of transmission lines, over 70%, in the United States are outdated, and are near 25 years old.[20] The average age for power transformers that power over 90% of the country is 40 years old.[21] Power lines, whether old or new, are susceptible to storm damage, and, in 30% of cases, the power line does not automatically shut off.[22] This can happen when the fallen line draws too little electric current to activate a fuse or circuit breaker.[22] These high-impedance faults (HiZ) can cause high-energy, high-temperature arcing that can cause ignition.[22]
Contact with vegetation and foreign objects
[edit]Vegetation contact, and contact with foreign objects, such as trees, are leading causes of wildfires.[1] In California, these factors were responsible for 35%, and 18%, respectively, of utility-related fires larger than 10 acres.[1] Strong winds have been known to exacerbate these problems.[1] Live wires can ignite dry vegetation and fuels, and fallen trees can result in downed lines.[22]
Conductor slap
[edit]Power lines are traditionally designed with significant clearance between conductors, this prevents them from contacting under normal operating conditions.[23] Under poor conditions, line conductors can slap against one another; this causes high energy arcing, and, occasionally, small bits of molten metal (generally aluminum) are ejected.[24] These ejected pieces of molten aluminum can ignite wildfires.[22]
Component failure
[edit]Many components, such as switches, transformers and insulators, contain thousands of complex circuits and parts.[25] While often able to effectively provide service for decades, they do eventually fail.[22] Occasionally, before complete failures, there is electric arcing and sparks that are too small to be detected by fail-safe sensors.[22] These sparks and electric arcs can result in the ignition of vegetation or foreign objects.[22]
Solutions
[edit]Electric companies are investigating solutions such as burying power lines, installing sensors, and using software to monitor cables and automatically shut them off.[3] In 2023 wildfire mitigation plans, Californian utility companies proposed over $9 billion to mitigate factors that cause wildfires.[26]
References
[edit]- 1 2 3 4 5 "REDUCING UTILITY-RELATED WILDFIRE RISK" (PDF). energysafety.ca.gov. Public Utilities Commission and Boston Consulting Group. December 2020. Archived from the original (PDF) on 2022-02-24. Retrieved 18 October 2024.
- ↑ Park Williams, A.; Allen, Craig D.; Macalady, Alison K.; Griffin, Daniel; Woodhouse, Connie A.; Meko, David M.; Swetnam, Thomas W.; Rauscher, Sara A.; Seager, Richard; Grissino-Mayer, Henri D.; Dean, Jeffrey S.; Cook, Edward R.; Gangodagamage, Chandana; Cai, Michael; McDowell, Nate G. (March 2023). "Temperature as a potent driver of regional forest drought stress and tree mortality". Nature Climate Change. 3 (3): 292–297. doi:10.1038/nclimate1693. ISSN 1758-6798.
- 1 2 Penn, Ivan (22 March 2024). "Utility-Caused Wildfires Are Becoming a National Problem". The New York Times.
- ↑ Boxall, Bettina (5 January 2020). "Human-caused ignitions spark California's worst wildfires but get little state focus". San Diego Union-Tribune. Archived from the original on 19 June 2023.
- ↑ "How an Australian State Fought Back Against Grid-Sparked Wildfires - IEEE Spectrum". spectrum.ieee.org. Retrieved 2024-10-06.
- ↑ "Black Saturday 2009". www.cfa.vic.gov.au. Retrieved 2026-05-07.
- ↑ "VCFD determines cause of the Thomas Fire – Ventura County Fire Department". fire.venturacounty.gov. Archived from the original on 2025-11-05. Retrieved 2026-05-07.
- ↑ Zimmerman, Jeffrey. November 2018 Camp Fire. National Oceanic and Atmospheric Administration, Jan. 2020, https://www.weather.gov/media/publications/assessments/sa1162SignedReport.pdf.
- ↑ Derbeken • •, Jaxon Van (2019-12-06). "New Images of PG&E Hooks on Camp Fire Power Line Released". NBC Bay Area. Retrieved 2024-10-06.
- ↑ "2019 Kincade Fire After Action Report" (PDF). Sonoma Operational Area and the County of Sonoma Department of Emergency Management. March 2020. Retrieved May 7, 2026.
{{cite web}}: CS1 maint: url-status (link) - ↑ "Incident Investigation Report" (PDF). California Public Utilities Commission. June 2, 2022. Retrieved May 7, 2026.
{{cite web}}: CS1 maint: url-status (link) - ↑ "Dixie Fire Incident Investigation Report" (PDF). California Public Utilities Commission. October 9, 2023. Retrieved May 7, 2026.
{{cite web}}: CS1 maint: url-status (link) - ↑ "Deadly Maui wildfire was sparked by downed power lines, investigation finds". Yahoo News. 2024-10-03. Retrieved 2024-10-06.
- ↑ Leonard, Matthew (2024-08-04). "The Maui Wildfires Were Massive. These Numbers Help Us Comprehend Them". Honolulu Civil Beat. Retrieved 2026-05-07.
- ↑ "News: MFD and ATF conclude Aug. 8, 2023, Lahaina fire was one fire caused by re-energization of broken electrical lines". www.mauirecovers.org. Retrieved 2026-05-07.
- ↑ "Decayed power pole sparked the largest wildfire in state history, Texas House committee confirms". Marfa Public Radio, radio for a wide range. 2024-05-02. Retrieved 2024-10-06.
- ↑ "Smokehouse Creek Fire: Lessons from Texas' Largest Wildfire". OroraTech. Retrieved 2026-05-07.
- ↑ Souliotis, Yannis; Maltezou, Renee (15 August 2024). "Faulty power cable may have caused Greece's worst wildfire this year, sources say".
- ↑ "Southeast US Wildfires: Drought Fuels Damage in South Georgia and North Florida". JD Supra. Retrieved 2026-05-06.
- ↑ U.S. Department of Energy. Quadrennial Energy Review Energy Transmission, Storage, and Distribution Infrastructure. 2015.
- ↑ Tompkins, Al (2022-12-27). "When will we update our power grid?". Poynter. Retrieved 2024-10-03.
- 1 2 3 4 5 6 7 8 "How Do Power Lines Cause Wildfires?". Texas Wildfire Mitigation Project. 2014-02-13. Retrieved 2024-10-06.
- ↑ "Power Line Safety". International Sign Association. Retrieved 2024-10-07.
- ↑ Short, Tom (10 October 2024). "Conductor Slap" (PDF). Electric Power Research Institute.
- ↑ "Transformers: Explaining the basics". CALCO. 10 October 2024.
- ↑ Warner, Cody; Callaway, Duncan; Fowlie, Meredith (February 2024). "Risk-Cost Tradeoffs in Power Sector Wildfire Prevention" (PDF). Energy Institute at Haas.