Power Lines and High Winds Caused Thomas Fire

Thomas Fire (VCFD)

By edhat staff

The Ventura County Fire Department (VCFD) has determined the Thomas Fire was started by power lines coming into contact during high winds.

VCFD released their report on Wednesday stating, “A high wind event caused the power lines to come into contact with each other, creating an electrical arc. The electrical arc deposited hot, burning or molten material onto the ground, in a receptive fuel bed, causing the fire. The common term for this situation is called ‘line slap,’ and the power line in question is owned by Southern California Edison.”

The Thomas Fire sparked the evening of December 4, 2017, and burned a total of 281,893 acres; destroying 1,063 structures and resulting in one civilian and one firefighter fatality. It burned for nearly 40 days, threatening the cities of Santa Paula, Ventura, Ojai and Fillmore, Carpinteria, Montecito, and Santa Barbara, as well as many unincorporated communities.

It was declared 100 percent controlled on January 12, 2018.  Nearly 9,000 emergency personnel were working the fire with emergency responders traveling across the western United States to assist.

The Thomas Fire has also been labeled a contributing factor of the debris flow in Montecito on January 9,  2018, that caused 23 deaths. An estimated 0.5 inches of rain fell within a five-minute period around 3:30 a.m., which caused mud and boulders from the Santa Ynez Mountains that were significantly affected by the Thomas Fire burn areas, to flow down creeks and valleys into Montecito homes.

VCFD investigators were dispatched with initial attack resources to the wildfire and immediately began working to determine its origin and cause. An investigative team was comprised of the following agencies: CAL FIRE, Ventura County Sheriff’s Office (VCSO), Santa Barbara County Fire Department, and the U.S. Forest Service (USFS).

To view the Thomas Fire Investigation Report, click here.

Edhat Staff

Written by Edhat Staff

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  1. No surprise here. Unfortunately, Lives were lost along with property and valuable watershed. Power Companies refuse to upgrade their infrastructure, instead choosing HUGE multi-million dollar management bonus’ and rewards to shareholders. Most of the large conflagration fires in the Western States are caused by above ground powerlines. That being said, the forest(s) mis-management has gone unchecked for decades, again a factor in these conflagrations that cost lives and billions of taxpayer dollars to fire suppression organizations, which has become a large income generator for fire departments across the State. These Wildfires are not going away-not so much due to “global warming” but mostly to the above mentioned causes…

  2. Doubt that there are many apartment buildings in the back country. Homeowner will have to pay for it to live in the backcountry, just as they do now. Cost of solar is coming down all of the time. Will still be connected to the grid, just not during the high fire danger days. The alternative is to not do anything, and believe me when I tell you SCE is going to cut the power at the slightest hint of danger to avoid liability in the future.

  3. Humans and human technology are responsible for most wildfires. The combination of above-ground power lines, tinder-dry terrain, and high winds is a huge part of the issue. This excellent article from The Atlantic clarifies the problem: https://www.theatlantic.com/technology/archive/2018/05/power-lines-are-burning-the-west/561212/ The only viable solution is to locate power lines underground. Unfortunately, that would be a huge and extremely expensive undertaking.

  4. The specific root cause mentioned in this article was “line slap”. How do you prevent it? As someone mentioned, you can bury the power lines, but that has huge environmental costs in undeveloped areas (you need to dig big trenches AND roads to access every in of that trench and maintain these roads and trenches as opposed to pole mounted lines which can rely heavily on helicopters). In developed areas, burying lines requires digging trenches or boring conduit through a maze of existing pipes, tree root systems, and buildings. Line slap can be controlled by placing poles/towers closer together but that’s expensive and power in California is already far more expensive than just about anywhere outside of Hawaii. $1.00/kWH sound good to everyone?

  5. Appreciate the last two posts. I’ve often hiked the urban interface and front country, looked at the smaller and larger power lines, and thought about what it would take to underground them. lt’s a multi-dimensional problem that can get very expensive to solve . On just the undergrounding issue alone, that Atlantic article estimated a minimum of $1M per mile for undergrounding (more in rugged terrain).

  6. Power companies such as SCE have in the past invested in drug stores and other money makers outside their industry (and lost millions on bad investments) rather than putting the money back into upgrading their public utility systems and service. They are in the business of short term profit, and not maximizing service to the community. This is the same corporation that used money from consumer electric charges to fight the California Coastal Act in 1976. Edison was sued and lost in court and had to refund all the money illegally taken from consumers back to them. Nothing will change if their one biggest goal is to make a profit. They (and us) are reaping what they’ve sown in their short sighted, profit driven management of a key public utility.

  7. Nobody has mentioned the possibility of turning off the power in high wind conditions but equipping remote houses with solar panels and backup batteries? That’s where we are headed anyway, might as well get there a little sooner. Then you don’t have to rely on fire-prone transmission corridors so much.

  8. Turning off the power means a lot of different problems for a lot of different people. (Medical devices, heating, air conditioning, or even fans, etc.) And the cost of having alternative power can be prohibitive for many. What about people in apartments? High winds can last for days. Solutions are not all that simple for everyone.

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