Updated: 10:05 p.m. May 21
First discovered: 3 hours ago, 6:16 p.m. May 21
Initial location: La Sierra Avenue and Tin Mine Road, South of El Sobrante, Riverside County, Calif.
Fire unit: Cal Fire Riverside Unit
Fire type: Wildfire
Fire name: Sierra Fire
Sierra Fire initially started today at 6:16 p.m. in Riverside County.
It has burned 20.1 acres after being active for three hours. As of Wednesday evening, the fire has been fully contained. Investigations into its cause are still ongoing.
Cal Fire status update
Situation Summary
As of 8:53 p.m., the Sierra Fire has been declared 100% contained. The fire burned approximately 20 acres.
Fire containment
What does 100% containment mean?
Note that full containment doesn’t mean the fire is completely out. In this case, it means that the wildfire has been fully enclosed by a control line and it is now stopped from spreading. A fully contained wildfire may continue to burn within the containment perimeter but is not likely to spread.
However, there’s a significant difference between containing and controlling a wildfire. After the fire is fully contained, the next step is to control it. Controlling a fire means ensuring that the fire can’t spread or cross the containment line.
Containment is part of a larger plan for managing a wildfire. It is normally expressed as a percentage and it refers to how much of the fire perimeter has been surrounded/enclosed by a control line that firefighters create. The containment percentage indicates a certain level of control, but it doesn’t always correlate to safety level. Also, it’s important to note that containment doesn’t mean a fire is out.
How is containment measured?
The incident’s central command constantly receives progress reports from firefighters on the ground. As the fireline is constructed, inspected or reinforced, mappers record those details to adjust the containment percentage. The percentage tells the public how much of the fire perimeter is believed to not go beyond the control lines.
Source: Cal Fire