Update: Rumsey Fire in Colusa County remains 100% contained by Monday morning

Published Jul 27, 2026 #Rumsey fire

Updated: 6:31 a.m. July 27

First discovered: 1 week ago, 3:40 p.m. July 20

Initial location: Off Sand Creek Road, near the Yolo and Colusa county border, Calif.

Fire unit: Cal Fire Sonoma-Lake-Napa Unit

Fire type: Wildfire

Fire name: Rumsey Fire

Rumsey Fire initially started 3:40 p.m. July 20 near Off Sand Creek Road, near the Yolo and Colusa county border in Colusa County, California.

By Monday morning, it had ravaged 396 acres. As of Monday morning, the blaze has been fully contained. Currently, details about the cause of the fire are unknown.

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 firefighters have managed to get a line completely around the wildfire’s perimeter 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