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#wildfire mitigation strategies: a thread. The goal of many #wildfire mitigation strategies is NOT to stop a fire. It is to alter fire behavior, lower intensity, reduce embers, facilitate safe evacuation, and support firefighter safety. 1/n
Fuel treatments have repeatedly brought crown fire to the ground, lessened spotting distance and density of embers, and often occur along roads specifically to mitigate the situation we saw in Paradise -- trapped vehicles with trees falling on roads and high fire intensity.
Fuel treatments also give firefighters a safe place to work, when they have time to get there (also why they often occur on roads). Burnout operations are often anchored on fuel treatments, and many fire perimeters include sections of fuel treatments that were successful.
Defensible space and structure hardening are also critical mitigation strategies for many of these same reasons. Bc we also have earthquake building codes in much of the US (esp CA), houses simply cannot be built "fireproof" out of cement blocks or bricks.
Instead, structure hardening seeks to block ember intrusion (vent screen, boxed eaves, sealed multi-pane windows, wood attachments removed) and reduce likelihood of the fire starting INSIDE the house. Newer CA building codes address this, but only on homes built post-2006.
Structure hardening works great, all other factors being equal. It buys firefighters time, allowing them to safely "follow" a fire front and remove burning debris from hardened roofs/decks, and put out spots around homes. But homeowners must also pay attention outside the home.
Flammable deck furniture, wooden attachments like trellises, and highly flammable landscaping (eg wood chips, juniper bushes, cypress trees) right next to homes compromise hardening. Embers land here and easily ignite, then ignite the structure. See great @disastersafety work.
Defensible space, by definition, implies that someone (usually a firefighter) is going to defend it. So defensible space essentially needs to be a mini-safety zone for whoever is defending the structure. Defensible space hasn't failed if it doesn't stop a fire cold.
Defensible space buys time for firefighters (or homeowners in places where Stay-and-Defend is optional) to safely defend their home by putting out small spots, watching for large brands and embers landing on the structure, and watering down house. Requires low fire intensity.
Prescribed fire is a tool, along with thinning, lopping limbs, mastication, and many others, that reduces the amount of flammable biomass ahead of time. In many places it also restores ecosystem function, and in some places it is simply the most effective fuel reduction method.
All of these #wildfire mitigation strategies work together across multiple spatial and temporal scales, and all take a lot of work (and $$). #wildfire is incredibly complex, so the solutions must also be complex.
Suggesting that some tools don't belong in the toolbox is like trying to build a house with only a hammer and some nails. Yes, we know a hammer is an effective tool, but you can build a much better house with a lot more tools, and figuring out what works best for a given place.
We can't STOP #wildfire. Mitigating is NOT prevention. We will ALWAYS have wildfire. But we can reduce disasters by lowering fire intensity, reducing ember cast and ignition, facilitating safe evacuation, buying time, and subsequently saving lives.
