‘Watch Duty’ Is Saving People From the L.A. Wildfires. Here’s How the App Actually Works
This week, as wildfires erupted across Los Angeles, residents anxious for real-time information about the rapidly-shifting perimeters of the fires passed around a tip: download Watch Duty.
The app is run by a nonprofit nominally based in Sonoma County, but is staffed by a dozen employees and hundreds of volunteers scattered around the world. It maps wildfire boundaries in real time, alongside evacuation orders and warnings, fire weather advisories, and the location of shelters. Just three and a half years old, it has become an indispensable tool as the threat of wildfires has grown across the West.
During a single 10-hour span as fires raged around L.A. on Wednesday, three-quarters of a million new users downloaded the free, ad-less version and over the course of that day, it was serving 500,000 users every minute, Nick Russell, the app’s VP of operations tells Rolling Stone. (At the same time, Russell says, two other evacuation systems in Southern California went down, overburdened by too many requests; he declined to name them.)
The event that began on Tuesday, Jan. 7 represented the largest response the app has mobilized since its inception in 2021. Back then, it was mostly operated by retired firefighters, dispatchers, and first responders listening to radio scanners for reports of possible wildfires. They were brought together by John Clark Mills, a serial tech entrepreneur who moved to an off-grid property in Northern California’s rural Sonoma County after he sold his last company in 2020.
Mills, Russell says, had been living in Sonoma County for six months when he saw helicopters flying overhead en route to a fire. He could see smoke but couldn’t find reliable information about how close the fire was, where it was expected to go next, online. In August 2021, he launched Watch Duty as an volunteer-run organization that offered real time wildfires alerts in three counties. Today, the app operates in 22 states and 1,476 counties, and has developed a sophisticated system to monitor events like the one still unfolding across the Los Angeles area.
Russell says his team at Watch Duty started seeing the first indications of a “perfect storm” readying to bear down on Southern California five to seven days before the first fire broke out. By Sunday, he says, they’d received word that the the National Weather Service was poised to declare a “PDS” — Particularly Dangerous Situation, “the highest level of fire weather conditions in existence,” he says — due to the bone-dry conditions (rainfall at just 10 percent the annual average), low humidity, and unusually powerful Santa Ana winds.
The Santa Anas — the offshore winds that Raymond Chandler once wrote “come down through the mountain passes and curl your hair and make your nerves jump and your skin itch” — are legendary in Southern California. They start at the top of the Santa Ana range, then speed down hill, growing in pressure and warming the air. But the winds blowing across Los Angeles county this week approached hurricane strength, and they were colder than usual, affecting a broader swath of the landscape: the ideal conditions that meant it was only a matter of time before a fire, like the one that ignited in the Pacific Palisades on Tuesday morning, broke out.
When it did, the team — staffers and volunteers operating remotely from their own private posts across Oregon, Washington, Idaho, even New Zealand — snapped into action.
Keeping the maps current involves collecting and vetting data from hundreds if not thousands of sources. While the app once enlisted volunteers to monitor scanners manually — leaving them on all day, hearing calls for car accidents and other emergencies — today, it employs 18 “Echo Radio Devices” that monitor hundreds of first responder of emergency scanners radio frequencies. Whenever any wild land-specific firefighting resources — aircrafts, bulldozers, land crews — are dispatched, the devices automatically capture and transcribe the audio snippets from the radio channels, then send them via Slack to the team responsible for the area where the call originated.
From there, a different person is responsible for each piece of the puzzle. The fire perimeter data is collected by California’s Fire Integrated Real-Time Intelligence System Program, aircrafts deployed from bases in Central and Southern California that circle a fire, broadcasting video to firefighters on the ground. The same data is beamed to Watch Duty, cross-checked by a human, uploaded, and updated in real time as the situation evolves. Meanwhile, evacuation data is being collected and cross checked with city and county agencies. The whole operation is supported by grants (Google gave $2 million last year) as well as subscriptions to a Watch Duty Pro, a version of the app that includes information specific to utilities and first responders.
As the fires continue to rage, Russell says the app’s team of engineers are working to scale their systems to meet demand, and the team of reporters are monitoring shelter capacities, and working with disaster response groups to add food and aid distribution and other aid sites to the map. “Any resources that are there for folks that have been affected by these fires, we want to start getting those communications out, so people aren’t kind of standing out in the wind waiting to figure out what’s next,” he says.
