How Prefire Management Project Helped in the Old Gulch Fire

FARSITE, a spatial fire spread model, was used to assess the relative effectiveness of prefire fuel modification projects on potential outcomes from a 1992 wildfire in Calaveras County, California. This very large and damaging wildfire burned approximately 17,000 acres and cost nearly $29 million in suppression costs and damages. Recent prefire projects involving significant fuel modification altered fire behavior on two fronts and were considered important in reducing final fire size and damage. This analysis uses computer modeling to assess the tradeoffs associated with these treatments. In both instances, the fuel treatment project showed significant effects on reduced fire spread rate, fireline intensity, and eventual fire size at the end of the simulation period. These results were interpreted against similar modeled scenarios without the fuel modifications in place. The example shown below compares the growth of the fire over a 24 hour period with and without the Skull Ranch Forest Improvement and Fuel Reduction Project. As is evident, as the fire crosses into the treated area (gold) its advance is significantly reduced. Modeled fire size at the end of the simulations were 4,114 acres with the project, and 6,220 acres without the project. More importantly, the project effectively clipped the fire front from its up-canyon advance on the community of Arnold (as shown in pink in the upper right), where property values were assessed at greater than 1.6 billion dollars.

NO TREATMENT

WITH TREATMENT

Click on images to see larger maps

Full Report on exploring FARSITE modeling of prefire projects on the Old Gulch Fire
Coming soon.

FOR MORE INFORMATION

Contact David Sapsis via e-mail at dave.sapsis@fire.ca.gov or by phone at (916) 445-5369

Last edited on June 17, 1997 by David Sapsis