2009 Station Fire

Just two years earlier, Southern California experienced a natural wildfire due to atmospheric conditions, involving Santa Ana winds and decreased amounts of rainfall, and the type of soil and vegetation, which might even require fire to continue to grow. The station fire of 2009, however, was under investigation as an act of arson. This fire, which is considered the largest recorded fire in Southern California, which began in the Angeles National Forest in August 26, 2009 and reached its largest perimeter on September 2, 2009. This fire was not 100% contained until October 16 of that same year. The fire began with a relatively small perimeter and quickly consumed an approximate 20,000 acres before spreading north. The fire not only spread north, but also spread in size until it burned an approximate 160,000 acres, putting the nearby cities of Pasadena, Glendale and Burbank in danger. 

This perimeter of Los Angeles county includes the beginning August 29 perimeter of the 2009 Station Fire,  perimeters from the end of August to the beginning of September and finally the largest perimeter that burned on September 2. The blue lines, referenced as "dlt_riv", represent the rivers and streams that flow through Los Angeles County.

Wildfires, as a result of natural causes or human, pose a threat to all surrounding areas. Populated cities near by are effected immediately by the offset of large amounts of carbon dioxide, carbon monoxide, and H20 into the atmosphere, which will not only impair visibility but also respiration. However, over larger periods of time the effects will be felts as well. Wildfires damage the soil and increase erosion, which in turn will allow rainfall to cause flooding and debris flow and aid in the process of landslides. 

          Post-fire debris flow is most common in areas "underlain by sedimentary or metamorphic rocks that have more than about 65% of the area burned at moderate to high severities." (USGS) Although the data provided by 'Los Angeles County Enterprise GIS' shows that the area surrounded by the Angeles National Forest includes a potential debris flow rate of 0-19%, the immediate surrounding areas of the largest perimeter (of September 2, 2009) show a rate of 60-70% potentiality for debris flow. The Northeast side of the fire perimeter shows a 80%-100% potentiality for debris flow. These areas all are downslope from the fire perimeter and are immediately connected to the perimeter through rivers and streams, which will aid the accumulation of rainfall water, runoff and flooding if a heavy rainstorm were to occur after a fire. 


        Debris flow can happen even two years after a large fire storm in accordance to heavy rainfall. Areas that were once unburned in Southern California, now are easily triggered by rain to move downslope due to the thinning of the soil layer and the loosening of the rock. 


       The information on potential debris flow is of course constantly changing, with atmospheric conditions constantly in flux and the unpredictability of amount of precipitation, along with the unpredictability of a firestorm this size. These potential debris flow area maps do not ensure the exact percentage, however, they give an idea as to why certain areas are more likely to experience debris flow. These conditions are due to slope, rock type, soil type and the data also takes into account the probability of rain. These situations prove that all parts of nature are connected and that even a fire can cause a flood. 

References

NOAA National Climatic Data Center. "State of the Climate: Wildfires for Annual 2009." National Oceanic and Atmospheric Association.  Published online December 2009. Retrieved on June 15, 2012 from <http://www.ncdc.noaa.gov/sotc/fire/2009/13.>

Cannon, Sue. "2007 Southern California Wildfires and Debris Flow Studies." U.S. Geological Survey. Margo L. Johnson. <http://pubs.usgs.gov/fs/2005/3106/pdf/FS-3106.pdf>

"Incident Web Information: Station Fire." Incident Web Information. Updated November 10, 2009. <http://inciweb.org/incident/1856/>

"Fires, Floods, and Waterseds." The Santa Clara River Parkway. November 2007. <http://www.santaclarariverparkway.org/theriver/fireflood>




Chang, Alicia, and John Antczak. "Post-Wildfire Worries: Floods, Damaged Ecosystem." US News, Science. September 8, 2009. <http://www.usnews.com/science/articles/2009/09/08/post-wildfire-worries-floods-damaged-ecosystem>