 |
| Half a block from us |
I live in the mountains in a redwood forest in Central Coast California. I love this place and the deep serenity it has brought me. But there’s a down side to every locale, and wildfires are part of the ecology of this region. Much of the plant life, including redwoods, has evolved to survive and even thrive with periodic conflagrations. Humans, on the other hand, aren’t too fond of having their homes burned down, so they put out little fires, allow underbrush to build up, and are loathe to control flammable invasive species (like broom). Increasingly long, hot, dry summers that are the result of climate change turns the region, like many in the West, into a tinderbox. Last summer’s freak lightning storm ignited thousands of small fires that merged into huge ones. I’ve written earlier about my experience being evacuated and watching, day by day, as fires engulfed this area but the heroic efforts of fire fighters spared my own street.
Almost as soon as the mandatory evacuation orders were lifted, local authorities began an campaign of education and preparation for the next phase of this rolling disaster: debris flows. Debris flows are a type of mudslides.
Debris flows … are fast-moving downslope flows of mud that may include rocks, vegetation, and other debris. These flows begin during intense rainfall as shallow landslides on steep slopes. The rapid movement and sudden arrival of debris flows pose a hazard to life and property during and immediately following the triggering rainfall.1
In other words, debris flows are rivers of cement 15 or more feet high and moving at up to 40 mph. If you can see it, it’s too late. There’s no way to prepare except to get out of the way. Debris flows caused massive property damage and over 20 fatalities in 2018 in Montecito, Southern California. Our local agencies were understandably concerned.
We all studied the maps of debris flow risk and watched the weather forecast. November and December passed with only occasional gentle showers, well belong the threshold for triggering a debris flow. Some of us began to relax, hoping for a dry “La Niña” year. Old timers warned that often the real rains don’t set in until January. They were right.
