SAN DIEGO (KGTV) — After more than a week of thousands of firefighters battling flames, hot spots and rugged ground conditions, the Border 2 fire is out now, but for investigators, the work is just getting started.
"It is interesting to see investigators go from such a large fire and to be able to use a systematic process to get that fire, read the clues, look at the traces that the fire left behind, to get that to a smaller area," Fire Captain Robert Johnson with Cal Fire San Diego County Fire says.
Fire scenes, much like crime scenes, tell a story.
Investigators follow a trail of blackened earth and burn patterns, all leading them closer to the origin.
But even with fire investigation technology advancing over time, Cal Fire says it can take hours, days or weeks to figure out the cause.
Investigators work methodically placing flags, gridding out sections, digging beneath the ash. Every burnt leaf or melted object, a possible clue.
“These signs that the fire left behind, they're gonna go in a systematic method and mark these indicators, and then when they step back," Captain Johnson says. "It's gonna paint a picture of the direction of travel.”
But not all clues are physical. 911 calls, eyewitnesses and video surveillance like HPWREN's can also help piece together the moments before flames ignited. But even a drop of rain can erase crucial evidence.
"Any types of exterior elements, human interventions could compromise the clues left behind by the fire and as well as any potential evidence," Johnson tells ABC10 News.
According to Cal Fire almost all fires in California are human-caused. Sometimes intentional, other times a spark from a tool or a holiday celebration gone wrong.
In 2020 alone, 120 arson arrests were made across the state, connected to fires that burned over 44,000 acres.
For now, the Border 2 fire and those in the Los Angeles region remain under investigation, but some fires, Johnson says, will never have a final answer.