Early last year, as hurricane force winds drove five separate fires across the Los Angeles Basin in less than 36 hours, CAL FIRE’s maps became as critical as its engines and aircraft. Residents refreshed dashboards, media outlets embedded live incident maps, emergency managers watched evolving perimeters and evacuation zones, and hundreds of millions of web requests hit CAL FIRE’s geospatial infrastructure in a matter of days. The system bent, exposed its weak points and became the catalyst for a complete overhaul of how one of the nation’s largest wildland fire agencies leverages mission critical GIS.
January 2025: When Maps Became Lifelines
In the early morning of January 7, smoke over Los Angeles ignited what became the Palisades Fire. Within an hour, the fire exploded from 10 acres to more than 200 acres and forced rapid evacuations. In just three hours the footprint grew past 1,200 acres as the Santa Ana winds pushed flame fronts across neighborhoods, canyon systems and critical infrastructure.
That night the Eaton and Hurst fires started under the same wind conditions. By the afternoon of January 8 the Lydia and Sunset fires were burning too. Five fires in the LA Basin in under 36 hours meant five evolving sets of perimeters, road closures and evacuation warnings layered over one of the most densely populated urban regions in the country.
Christina Brunsvold, CAL FIRE’s Lead GIS Administrator and Project Manager described the information pressure. “During a fire, several questions are always asked. Residents want evacuation updates. Emergency managers need situational awareness. Media organizations want to share accurate maps and partner agencies require operational data. And millions, and I mean millions of people simply want to know whether their homes and communities are affected,” she said.
GIS had become one of the primary ways people understood what was happening. In an evening briefing on January 7, the governor directed Californians to CAL FIRE’s website, where a first‑of‑its‑kind incident map sat directly on the homepage. Evacuation zones changed rapidly as the fires grew. New polygons appeared, existing zones shifted and incident parameters updated in near real time. All of this translated operational data from the field into clear, actionable information for the public.
“What made this event unique wasn’t just the fire activity. It was the location and the scale of the public consumption,” said Brunsvold. “Interactive maps became essential infrastructure. People refreshed dashboards continuously. They shared maps on social media and they demanded real time spatial information to make critical decisions. The audience wasn’t thousands. It was hundreds of millions.”
That surge exposed a harsh truth. CAL FIRE had been serving both public‑facing content and internal operational services from the same platform. The very success of their maps in building public trust drove a flood of requests to Esri’s ArcGIS Online that pushed the environment beyond its capacity and degraded performance for everyone.
From Stress Test to Overhaul
Rather than treat the problem as a simple outage, CAL FIRE’s Information Technology Services team treated January’s firestorm as an architectural stress test. “This is where the story becomes one of collaboration,” Greg Mattis, CAL FIRE’s Chief GIS Architect explained. He described how CAL FIRE and Esri worked side by side to adapt the existing environment while fires were still burning.
The combined teams focused on scaling services, optimizing content delivery, improving caching strategies and redesigning how critical datasets were published and distributed. The objective was not just restoring performance. It was ensuring that reliable information remained available at the exact moment people needed it most.
Mattis pinpointed the core issue. “Posting CAL FIRE operational and public facing content on the same platform was an issue. The volume of requests to ArcGIS Online grew so rapidly that performance degraded under the extraordinary load. Ironically, the very success in making the information publicly available created the challenge. The public trusted these maps so much the demand exceeded expectations.”
On January 8 CAL FIRE and Esri created a new ArcGIS Online environment dedicated solely to public facing content. That move shifted the enormous load generated by public traffic off the operational platform and into a separate, tuned environment designed for scale. After the re‑architecture, CAL FIRE’s usage graphs showed a clear inflection point where public requests migrated to the new configuration while internal systems recovered stability.
The proof came quickly. “Due to the architectural improvements, when the Hughes Fire ignited on January 22nd, the increased demand did not affect the system,” Brunsvold reported. The system had gone from overload to overhaul in less than three weeks.
Mattis distilled the lessons into three points:
- GIS is no longer just for back office support operations. It’s critical public infrastructure.
- Resilience matters just as much as capability.
- Partnerships between technology providers and operational agencies are essential for modern workflows.
The improvements strengthened not only CAL FIRE’s own environment but also created a model for other large‑scale operations facing similar demand spikes.
Paper Atlases to Enterprise GIS
To put January’s events into context, Mattis framed CAL FIRE’s GIS journey as three chapters: “where we came from, how GIS became mission critical during one of California’s most demanding wildfire events and where we go from here as we prepare for the next 30 years.”
For decades CAL FIRE operated successfully before digital mapping existed. Fire intelligence and forestry management relied on paper maps, local knowledge, radio communications, aerial observations and experienced personnel who understood the landscape intimately. Information is moved by phone calls, hand‑drawn maps and physical map books rather than web services and dashboards. “The system worked because people worked together,” Mattis recalled.
As GIS technology emerged in the 1980s and 1990s, CAL FIRE began integrating digital mapping into operations. Early GIS was a specialized capability reserved for trained analysts who processed limited datasets on expensive machines. Sharing spatial information between agencies was hard, but the obvious benefits included better situational awareness, faster planning and more informed decision making.
He described the two parallel paths of CAL FIRE’s adoption of GIS technology and Esri’s tech evolution from large room size computers to desktop mapping applications to enterprise systems, cloud services, mobile applications and real time analytics. As this happened, CAL FIRE also simultaneously evolved operationally. As GIS matured, CAL FIRE found new ways to integrate spatial information into nearly every aspect of the mission. “GIS stopped being just a mapping tool and became an operational platform,” Mattis noted.
CAL FIRE increased its use of digital mapping for incident management, fuels planning, resource allocation, aviation support, prevention programs and public information.Today at CAL FIRE, GIS supports more than just wildfires. GIS is embedded within programs protecting people and the resources of California. From fire preparedness actions and real time incident response to post‑fire analysis and the science in between, spatial data now underpins dozens of programs across the department. “GIS at the heart and the foundation of everything we do,” he said.
The Next 30 Years of Fire GIS
The third chapter of CAL FIRE’s story focuses on resilience and modernization. Wildfires are becoming more complex, and data volumes continue to grow. Sensors, drones, satellites, weather models, AI assisted analytics and real time reporting all feed the situational awareness picture that incident commanders rely on. The future of CAL FIRE’s GIS is not defined by one application or one platform. “It’s defined by adaptability,” Mattis said. “As you prepare for the next 30 years, the question isn’t whether GIS will continue to evolve. It’s how can we ensure it evolves in a way that best serves the firefighters, partner agencies and the people of California?”
We may not know what’s coming next. But the one constant for a world facing more frequent firestorms and heavier information loads that we can guarantee, according to the speakers, “We’ll still have a map.”
This content was derived from a presentation at the Esri Safety and Security Summit 2026.