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If you live in an area prone to wildfires, one phrase you often hear is percentage of containment. A 95% contained fire sounds a lot more comforting than a 5% contained fire. But what does it mean?

Containment refers to how much of the fire perimeter has been surrounded by a control line which fire managers are confident the fire will not cross. In other words, rather than describing how much of the fire has been extinguished, containment refers to the fire’s growth potential. Maps produced by fire managers show the perimeter of the fire outlined in red. Any portion of the fire declared contained is marked in black. The ratio of the red line to the black line determines the percentage of containment. Fire managers will not label a portion of the fireline “contained” until they are confident the fire will not grow farther in that direction.

Fire information officers have been fielding questions about containment on the Camp Creek Fire, especially since many areas of the fire have not grown in several days. The recent cool, moist weather has dampened fire activity, keeping the flames in the duff and downed woody debris. Firefighters have been using this window of favorable weather to remove trees along roads, take out “ladder fuels” (the lower limbs of trees, lichens, mosses, and shrubs that carry flames from the ground up into the canopy), and apply low-intensity fire in strategic areas to burn up duff and debris on the ground. However, if conditions again return to warmer and drier, fire activity could more closely resemble the active fire behavior seen on the first day of the fire. This would require wider and more robust fuel breaks to stop the fire’s progression. Until those larger control lines are in place, fire managers will hold off declaring containment.

After the fireline is constructed and improved, firefighters check the fire’s edge to ensure there is no heat within a defined distance of the fire line. This work is meticulous and time-consuming and can take days before any containment is indicated. The Incident Management Team will only change the status of a portion of the perimeter to “contained” when there is no heat on the perimeter and no chance that it grow in that area.

Rest assured, the low containment number doesn’t mean crews aren’t making progress on the Camp Creek Fire. Expect to see more black line on the fire perimeter map soon.

Two photos can be viewed below by clicking on the caption:

• Two firefighters monitor the fire's slow progression toward an established road. A low intensity fire is easier to contain than a fire that gets up into the tree canopy where embers can easily travel extend beyond the perimeter into unburned areas and start a spot fire
   
• Today's fire map shows the perimeter outlined in red, indicating there is continued work to strengthen lines before declaring any areas contained

Click the link below to watch a video from September 2nd, when the Incident Management Team announced the Camp Creek Fire had gone from 0% to 11% contained. The video includes an interview with the Division Supervisor, footage from the area where the containment was added, and an overview of the firefighting strategy going forward.

• September 2nd containment announcement (2:10)