Update: 30% containment reached for Morgan Fire in Contra Costa County

Published Jul 18, 2026 #Morgan fire

Updated: 7:55 a.m. July 18

First discovered: 30 hours ago, 1:14 a.m. July 17

Initial location: Morgan Territory Road and Marsh Creek Road, Mt. Diablo, Contra Costa County, Calif.

Fire unit: Cal Fire Santa Clara Unit

Fire type: Wildfire

Fire name: Morgan Fire

Morgan Fire initially started 1:14 a.m. July 17 at Morgan Territory Road and Marsh Creek Road, Mt. Diablo in Contra Costa County, California.

As of Saturday morning, it had scorched 50.8 acres. By Saturday morning, 30% of this fire was brought under containment. There is currently no information on the cause of the fire.

Fire containment

Interpreting what 30% containment means

The percentage indicates how much of the fire perimeter has been surrounded by a control line. In this case, it means that 30% of the wildfire is contained from spreading, while 70% is still uncontrolled.

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