October 12, 2017

Could the Northern California Wildfires Have Been Prevented Using Preemptive Power Outages and High-Resolution Weather Forecasts?

The catastrophic fires in northern California are still burning, with the death toll rising to 21 and damage estimates ranging into the tens of billions of dollars.

Is is possible that this tragedy could have been prevented or minimized by cutting the power to threatened areas before the fires started, using the best available weather forecast models to guide decision making?

This question is explored in this blog.

The proximate cause of the explosive fires were discussed in my previous blog.  We started with a very dry landscape, following the typical rain-free summer.  Wind picked dramatically on Sunday evening, with gusts to 40-70 mph over northern CA.  With offshore flow, relative humidities were very low.  And temperatures had been above normal.

But something initiated the fires and did so at multiple locations within a period of a few hours during the late evening on Sunday.  Although there is the possibility of arson, the most probable fire starter was arcing power lines damaged or shorted by falling trees and branches.

There is a history of California wildfires started by falling trees/branches during strong wind events, such as the 2015 Butte Fire near Sacramento that killed two and destroyed 550 homes.  And the there were reports of downed and arcing  power lines Sunday evening prior to the wildfire conflagration.

So if downed or arcing power lines was the key initiator of Sunday/Monday's fires what can we do to lessen the chances of a repeat of the tragedy?

Some media reports have suggested that the relevant power company (PG&E) was not effective in trimming vegetation around its power lines.   Certainly, an effective program of vegetation control around powerlines is essential.  And burying power lines in vulnerable areas would be wonderful, but very expensive (I have seen estimates of 1 million a mile)--but perhaps a reasonable investment.

But perhaps there is something else that can be done, which could provide substantial protection:  cutting the power to regions that are directly and immediately threatened by powerline-induced wildfires.

This is how it would work. 

This approach would only take place in regions and periods in which there are threatening amounts of dry fuels on the ground, making wildfires possible.

Thus, portions of California near vegetated area during the dry season (last summer, early fall) would be candidates.

Only areas with appreciable population would be candidates, thus remote areas would not be considered.

Only when dry atmospheric conditions and high winds are imminent and threatening, would pre-emptive blackouts be considered.  I would suggest using periods when gusts are predicted to exceed 40 mph (35 knots) with relative humidities less than 30% as a potential criterion.  If those conditions are forecast to exist within 6 hours or if they are observed, the power would be cut for the affected areas.

A very promising modeling system for such a purpose is the NOAA/NWS HRRR (High-Resolution Rapid Refresh) high-resolution model, which is run every hour, out to 18 h.    Here are the ten and four hour forecast of wind gusts valid at midnight Sunday/Monday (0700 UTC) for central CA.  Both forecasts are threatening, with predicted winds over 40 mph in many of the areas north of San Francisco where they were, in fact, observed.

Both showed the winds revving up above 40 mph around 8 PM and dropping below that value around 9 AM Monday morning. 

So the pre-emptive black out would run for 11 hours (8 PM to 9 AM) and folks would get a series of warnings that it would occur.   With modern numerical prediction, warnings of a potential blackout would be given a few days before, with a penultimate warning 6 hrs before, and a final warning an hour before.

Yes, there would be some inconvenience, but that would be minor compared to the benefits.  In the present case we are talking about saving roughly two-dozen lives and tens of billions of dollars of economic impacts.  And we haven't even touched on the negative impact on air quality for the heavily populated San Francisco metro area.

And there is the issue of false warnings or the "crying wolf" syndrome.  But a casual look at the climatology at a few locations around the area suggest that this was an unusual event, and that picking a realistic criterion (e.g., 40 mph gusts, August through October only, relative humidity below 30%) would produce very few blackout events.   I will explore this more during the next few weeks.

Is this a crazy idea?  If so, why?


  1. How will these "folks" get their *warning*?

    Thru there land-lines,which few have,or over the internet,or cell phones?
    All of these "folks" will need to sign-up for these warnings,and then will have to act ,especially the ones that need electricity for medical devises that are used for live threatening conditions...
    I don't believe "cutting the power" will be excepted as a practical maneuver.

  2. The major potential downfall to this plan would be false positives -- times when power was cut and forecast conditions failed to materialize.

    Before implementation and to properly set power-cut criteria, historic forecasts should be compared to the following real conditions over some long period of time to get an idea of how reliable the forecasts have been. That way the likely cost of unnecessary power cuts can be compared to the cost of tree trimming.

  3. Forestry services trimming a swath of trees at least on the west and north sides of power lines could also help. That would also help to reduce power outages.

  4. How many people would use fires for light or heat, and would that risk exceed the risk from electricity? How many car accidents occur during power outages? It's an interesting thought, but I don't know enough about the behavior of people during a power outage to know if the risk actually would go up or down.

  5. Why is this a crazy idea? Because you have not attempted to address the false positive question. There is a high cost to preventive blackouts. (Think about medical and business impacts.) Does historic analysis show that we can accurately predict when major power line induced fires are going to happen? I'm highly skeptical.

  6. Cliff, Fascinating stuff here. But I had another question: Could similar fires devastate the wine regions of Eastern Washington, say around Walla Walla, Yakima and Tri-Cities, or is it truly just a California phenomenon, especially because of the wind factor?
    John Marshall
    Bainbridge Island

  7. Thanks, Cliff,
    Fascinating stuff here. But I have another question for a future blog: Could similar fires devastate the wine regions of Eastern Washington, say around Walla Walla, Yakima and Tri-Cities, or is it only a California phenomenon, especially because of the high winds there?
    John Marshall
    Bainbridge Island

  8. I live in the coastal redwoods of extreme northern Calfornia. PG&E is constantly trimming trees it seems and we still have power outages from windfalls every year. We had a brush fire nearby from a down line just before the catastrophic fires to the south of us but luckily it was contained to 30 acres. I too wondered if preemptive power outages could help. Another thought is burying the lines. Seems like in the long run it would cost less than the constant and somewhat futile maintanance.

  9. Anyone familiar with the old Aesops fable "The Boy who Cried Wolf"?

    Can you imagine the indignant outrage at pre-emptive evacuations or power outages but nothing came of it? What if the red flag conditions went on for a week and no justifying fires occurred? The false positive has already been mentioned above and in this very blog it is relentlessly on display whenever a forecast big wind event fizzles and all the cynics loudly proclaim the forecasts are unreliable.

    I mean it's likely a good idea whatever the costs but just look at how the risk was handled already. Plenty of accurate forecasting and plenty of warning but exactly how many people self evacuated as a precaution? The effect here is common - no one does squat in the absence of threat but when the threat becomes obvious, it is too late for action. We react most to losses and in this case the immediate and unambiguous loss would be the terrible inconvenience of no power or evacuation. The loss of property and life is only an abstract concept, not even close to competing until it leaps out of the abstract and into reality.

    The past few days in California is the perfect example of our collective reaction to global warming risk to date, which is the persistent power of Loss Aversion...... otherwise known as risk incompetence.


  10. This has been thought of at CALFIRE. But there were many downfalls to the plan but one stood out.
    1. Many rural areas that have water systems are primed and operated by electricity, There are no standard fire hydrants up in the hills and mountains.

    After a power line caused fire in Nevada County CA back in the 90's PG&E was sued for millions. It also didn’t help PG&E's case that a girl was electrocuted a year before, in the same county, from a downed power line from the winter before and PG&E diverted funds for vegetation clearing around the pole that caused the fire.

    The real solution is to transition to below ground transmission all the way up to the service box of the house. As firefighters we wanted legislation but PG&E had many allies in Sacramento (I stepped over a charged line once on a fire and I didn’t even know it).
    The cost was around 1 million per mile to transition existing areas. This was a steep price. But residents who live in the urban interface should pay a higher service fee to offset the cost. But we know that is not going to happen. This fire may be a Erin Brockovich moment though.

    FYI Any new development in the urban interface must have underground transmission to the nearest possible service pole.

  11. Good to think of options. People should also know if their community or home is at risk and have an evacuation bundle ready. But beyond that I wonder id
    Fish more fireproofing with cleared
    Or green belts could have helped.

  12. It's a crazy idea, because there is a technical solution that does not require major inconvenience and danger. People's lives depend on power.

    The electrical code for households already requires arc fault circuit interrupter breakers. There must be a similar solution on a larger level. Undoubtedly, it would not be cheap to upgrade existing breakers with something fast enough.

    The advantage would be that the power only goes out when actual branches hit actual power lines. Perhaps more frequent outages, but caused directly by forces of nature. The need is obvious and the action is automatically justified.

  13. @Localgal - regulation is causing some perverse incentives here. Utilities get to recover maintenance cost for tree trimming and line repairs (opex) in the rate case pretty automatically. New build and upgrades (capex) - not so much, harder to make the case to regulators.

    For utilities, money comes in different colors and is not fungible.

  14. Another issue is the degree to which they maintain their lines. A number of friends of mine who were living at the historic Preston Ranch outside of Cloverdale escaped a big fire in the late 1980s with just the clothes on their backs if that that started when a power line simply broke - not from any wind or limbs. It was revealed later that there were several splices in between a few poles and one of these simply have become undone. When it fell into the grass, the fire started - then rushed up hill to the homes. It was only for the fact that someone was up at 3AM to head to work that they all got out of there in the nick of time.

    And then there was that pipeline explosion a few years ago. PG&E's bottom line doesn't appear to include maintenance!

  15. Shoulda, coulda, woulda.

    Will we learn from our mistakes?

    My money is on "No".

  16. I say change codes to make homes fire-resistant. Metal roofs should become the norm there. And a brick house, though more subject to earthquake damage, would be fire-resistant. Finally, they should encourage the use of fire-resistant vegetation to the extent possible, and not plant too near a home. Outside automatic sprinklers are also possible; that is how they saved our own Holden Village.

  17. We all need to deal blackouts occasionally. No excuse for not taking care of yourself.

    These days there are so many options. House batteries that can store electricity for use in the dark. Solar cells/arrays that produce power when the sun shines (you can sell any unused power to your local power supplier. Improved insulation for your home. A backup power generator (propane, gas, diesel) for long outages. Most people that need power to survive because of a medical condition already have a temporary backup in place./

    There are government programs will help with costs. Makes sense. It's cheaper than "rescuing" you. And I think it's nice to not to be totally dependent on someone else. I am personally disabled. Over time, I've accumulated tools to stay as independent as possible.

  18. Interesting proposal Cliff. I'd say that it would need to be done in conjunction with a number of other things, including subsidizing products like Tesla's power wall and/or generators, proper transfer switches for said generators, hardening of other infrastructure like traffic signals and cable TV repeaters to include or increase the size of backup batteries to make sure they last long enough to make it through.

    It wouldn't be easy, it would have to be a comprehensive project... but it is intriguing... and could be useful as disaster prep for the folks who get the backup systems...

  19. BTW, it was around one year ago when forecasters predicted that a portion of a large typhoon had broken off and was thisclose to obliterating most of the NW coast, as well as Portland and Seattle. When that forecast fortunately didn't materialize, many people came on to this blog (as well as many others) and proceeded to lambast the forecasters, instead of being grateful that fate had somehow intervened. So it goes. However, the Oregon Coast still got hit with a few tornadoes, but fortunately only property damage occurred. Here's a vid of my favorite place getting hit:


  20. I think the better idea would be to update power line infrastructures to prevent arcing and such. I'm not really sure exactly how to do this, but maybe some better sensory methods to determine when a power line is damaged and automatically shut down power to that section as close to instantly as possible.

    There would be way too many false positives for this theoretical, and it would never fly. But in places that experience powerful winds and weathers, there can definitely be improvements to the infrastructure to shut down power to these dangerous regions at the time something gets severed, falls over, or gets cut.

    This wouldn't just prevent fires, but also electrocution. And in general is a good idea to have better emergency cut offs for this kind of thing that can automatically trigger in case of an issue.

    But all this will cost a lot of money, and the justification for that money will have to be weighed against the potential loss of life. Which sucks, and I hate that that is even a factor to consider, but it's the way of the world. So how do we come up with the justifications for these infrastructure improvements? How can we factor hundreds of millions of dollars, if not billions of dollars, in upgrades, weighed against the free accidents that may or may not occur. And how to we make people understand that their tax money will be used towards the general safety and stability of the infrastructure around them?

  21. There is certainly precedent for this. Power is cut in areas suffering tornado damage immediately after a storm has struck and, occasionally, power is cut just ahead of a tornado's path. Power was proactively cut during Irma in Florida.

  22. Electrical fires cannot be the only cause of these, though. What if there was an artificial power outage, and then during that time something little forest fire anyway and it spread toward populated areas. Without power people wouldn't be able to get warnings to evacuate (from TV, radio, etc). You might have less frequent problems, but you might also end up with a much higher death toll that way when they do happen :-(

  23. I am not sure this would help. At some point, you would turn the power back on. If the lines were damaged when the power was out, when you energize the lines won't they arc and just start a fire at that point? Seems like devices could be added on both sides of the spans to detect an issue in the span and cut power.

  24. Mike Rogers,
    No this is not a problem. The power would only go on AFTER the winds had died...and the strong winds are needed to really rev up the fire. Plus, there would be time to deal with at least a few of the line breaks during the blackouts...cliff

  25. It's a temporary controlled outage. If the winds are truly strong enough and lines go down, then a power outage *would have occurred regardless*. It's an inconvenience, sure, but as stated the parameters for it are narrow and would be rarely met.

    The benefits seem pretty obvious when you consider the loss of life and property, livelihoods, from this firestorm. Arguing against this honestly seems pretty idiotic and illogical, like ignoring an evacuation order in the face of a (literally) life-threatening, immediately impeding natural event.

  26. Having lived through the scheduled blackouts last decade in Marin County, everyone can prepare for a preemptive blackout. High winds are not common, and when they come they are already full of disaster because there are always significant tree falls from all the trees that grew in size since the last big wind. Knowing the power will go out in advance might even be less stressful, as it usually goes out anyway, but then you can hope it will go back on as soon as the wind dies.

    Because of the previous history of the power crisis blackouts a lot of circuits were organized to keep key infrastructure powered, like hospitals, so not all power has to be cut.

    Finally, the power outs might spur progress in bond measures to upgrade the distribution network. It's incredibly sketchy and old already.

  27. Shutting off the power would prevent arcing. That sounds like a good idea. Yes, that would be an inconvenience, however, in these times we all need to be prepared to be without power or water. That is a fact of life. Yes, having the power go out may cause other problems related to individuals producing their own power and/or compensating for the temporary loss of power. Shouldn't individuals living in areas that experience dry weather and wind have a responsibility to be aware of all they can do to prevent fires from starting? Trim brush away from houses? Make sure generators are safe to use? Make sure all electrical wiring is up to code? Perhaps providing classes to inform people about how to prevent fires in the first place would be helpful.

  28. Very interesting discussion. On balance preemptive power outages may not be practical for all the reasons cited by people here. What I do think should happen are requirements that all new development and power line upgrades include burying the power lines where feasible. In Europe most countries bury power lines. There is a high cost up front but long term savings when you consider all the maintenance above ground power lines require every year after windstorms. And there are considerable aesthetic advantages as well.

  29. Refrigerators and freezers are typically good for upwards of a day without power, particularly if doors are not opened. People could take out enough food for the 'eleven' hours of no power and put it in an ice chest. Many would just ensure they had alternate power available for several hours. LEDs and a few battery charger packs can keep lights and computers going.

    Res how much a power company should spend on trimming and other reliability factors: How much are customers willing to pay for these things that cost a lot of money? After the fact cheaper than a fire, but many are opposed to paying.

    Losing power for several hours, particularly if you live in the country, should not be a big deal.

  30. People would turn to using generators, which, if they were gasoline powered, have the possibility of backfiring if not properly maintained causing fires of their own (specifically built in generators that people try to hide by planting shrubs adjacent to the housing). If 100,000 people were affected by blackouts and 10,000 people used gas powered generators, it is probable that one or more of them would backfire sending flames into nearby dry foliage).

    In the fire and wind prone regions with high populations the government should incentivize battery backup systems which are much safer in times of high fire danger. They should also outlaw gas powered generator systems for the length of the blackout. Only then would it be feasible to implement a "preemptive blackout" plan. Good luck enforcing the ban on generators though...

  31. Um, power outages? The big fires in Oregon had nothing to do with electricity. The conflagration in SW Oregon was started by lightning, as most wildfires are. The one in the Columbia Gorge was set by a 15-year-old arsonist.

    Too strong a word, arsonist? Nope, it turns out that the young firebug had posted a video on YouTube of himself setting a different fire in a field. The post was under his own name, but when it was discovered he changed his handle to -- get this -- "sorrynotsorry," and then deleted his account.

    In any case, these were not electrical fires, at least not in Oregon, Washington, and Montana.

  32. I think this is a great idea, but the issue is total cost. While putting the lines underground solves the problem the total cost is huge. Commenters have raised issues with cutting the power but I would bet that including solutions to those issues would still come in much cheaper than going underground. For example, provide people who need medical devices or need to prime their water pumps with generators or battery packs sized for a wind event. You could also invest in providing warning systems to people who don’t have the usual means of communication. In your scenario the warnings would give people the chance to prepare the backup systems. In addition, spending more money on tree trimming around the lines and educating people why the trimming is necessary even to their trees would still be cheaper than underground lines.

  33. Its feasible. Definitely not crazy. Like any other change, however, it would have to be well presented/sold/spun with very concise education. Convince people that there is something in it for them, well in advance, and they will get on board.

    As for burying lines, its spendy and not always a good idea in seismic prone areas. Yes, poles are ugly, but finding breaks is easy in addition to repairs begin cheap/expedient. After any disaster, getting the grid up is a priority for communication etc. Plus, so much of our lives demand power. It is more likely that we can live off bottled water for a while, forgo showers and poop in a Honey Bucket than go without the ability to charge our smart phones.

  34. @Placeholder - Cliff wasn't including any of those fires in his proposal. He's talking specifically about times, places and weather conditions that are known to be extremely dangerous sources of wildfires.

    More broadly, there is only one way that makes sense to figure out the best approach: quantify and compare the various costs and consequences of each proposed solution, and then adopt the one with the highest ROI. We aren't dealing here with perfect solutions - we're looking for the one with the least serious shortcomings.

  35. There will be a vigorous debate in front of the PUC about financial liability for PG&E. They has a long history of being found responsible for major wildfires because of inadequate maintenance of their power lines. There were some other factors as well. Valley and California Black Oaks were still weak from the previous extreme drought. Initial attack crews reported to dispatch of fallen trees that were blocking response. Also when there are “reported of power lines down” your initial attack units can’t go blindly in and start attacking the fire at the source. Until the lines are discharged and confirmed to such it is a very dangerous situation for fire crews.

    But in the end the private utility of PG&E will be faced with numerous class action lawsuits from private and public entities including the state to recuperate the firefighting cost. This may be the nail in the coffin for the private corporate structure of PG&E (to big to fail) and will reborn as a public utility. Shares have already plunged. But then again Goldman Sachs is still around.

  36. JB has the pessimistic, bullish take on PG&E; he can short the stock, and I am going long on it. PG&E is a massive regulated public utility. The state of California is not interested in allowing it to be gutted or seriously harmed; California PUC (Public Utility Commission) is thoroughly in bed with it, as with SoCal Edison, and the several lesser electricity distributing entities in the state. Consider the stock history. The previous shock to it was the massive destructive San Bruno pipeline explosion on Sept. 9, 2010 that killed 8 people.
    PGE was manifestly liable (a friend who participated in defending the company told me that they had no---or had effectively destroyed without detection---maintenance records). They were given a slap on the wrist. As Wikipedia puts it, “On January 21, 2017, PG&E was fined $3 million and ordered to perform 10,000 hours of community service for criminal actions of violating the Natural Gas Pipeline Safety Act and for obstruction of justice.” Needless to say, heads rolled into fat retirements at both PG&E as well as the PUC; sort of like banking after TARP; nobody went to jail.
    The stock fell from the $40’s to the high $30s after the blast and recovered in a couple of weeks. The 2017 penalties had no effect upon the stock price, which was in the low 60’s by then. The last 5 years have seen PG&E stock climb from the $40s to the $70s, and it declined to $54 with the Santa Rosa tragedy. Check out the option market on PG&E today, Oct 16.
    Regulated public utilities in California and other high regulation states (Washington?) thrive on the virtually guaranteed 6% return that they are granted by the efficiency regulations begun in the early 1970s that force “decoupling” of the earnings of the utilities from volume of their product; they are mandated by law to increase efficiency more than volume continually, in appliances, in usage, in generation of renewable power, and more recently in massive battery installations. California is the most energy efficient state in the union.

  37. I live in Klickitat County, which unlike Seattle or California isn't full of rich, lazy people who specialize in ripping each other off. I recently paid $26.37/foot to bury an electric line on my property, the cost including not just the line and the trenching but removal of two old poles and replacing them with two new power poles on each side of the 750-foot span.

    That would come to $139,244 per mile, but actually less because new poles wouldn't be needed. Again, however, you need to add a zero for anything done on the west side of the mountains for the greed, graft, stupidity, and laziness factors. If there's one thing we know about that part of the world, it's that your tribe never met a dollar it couldn't throw away.

  38. There is a case to be made for rebuilding with distributed renewables. If renewable power stations are situated in or near neighborhoods and on top of office buildings, the distance for power lines to travel can be greatly reduced. That reduces the miles of power lines exposed to rampant vegetation and wind-pruning that sparks fires. It also saves PG&E an enormous amount of money in tree trimming.

    Some are speculating PCG stock will bounce back this week"


Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

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