Remember when containment percentages used to actually mean something? They used to refer to the percentage of the perimeter on which a fireline was constructed. Now, they are more of a control percentage. A nebulous, subjective, judgement call. The official National Wildfire Coordinating Group’s Glossary of Wildland Fire Terminology defines “Contained” as:
The status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop the fire’s spread.
The Glossary defines “Controlled” as:
The completion of control line around a fire, any spot fires therefrom, and any interior islands to be saved; burned out any unburned area adjacent to the fire side of the control lines; and cool down all hot spots that are immediate threats to the control line, until the lines can reasonably be expected to hold under the foreseeable conditions.
Containment means a line is constructed, mopup is ongoing, and the spread is stopped, at least for now. Control means mopup near the lines is complete and the line is expected to hold. Why are incident commanders so reluctant to give an accurate report on the containment percentage?
We should go back to the orignal clearly defined procedure, based on a mathematical percentage of completed, black, line. If the perimeter is 10,000 feet, and 8,000 feet of the perimeter has completed black line, the containment percentage is 80. Period.