Date of Graduation
Master of Science in Environmental Management (MSEM)
College of Arts and Sciences
In California, the Sierra Nevada region is crucial for the state’s water supply. Unfortunately, forested areas in important Sierra Nevada watersheds are being increasingly threatened by the growing risk of large, severe wildfires and in turn so are the water supplies that they support. This paper addresses how these large fires facilitate sediment transport by removing soil’s vegetative and organic matter layers, changing soil properties, and inducing soil water repellency. Erosion and sedimentation are inevitable post-fire processes, and the predicted increase in large, severe fires and subsequent sedimentation are putting California’s water supply at risk. The risks these fires pose include degraded water quality, threats to infrastructure, and reductions in reservoir capacity. The region has evidence of post-fire sedimentation and documented sediment-laden flooding and debris flows, but there are huge data gaps in baseline data and very limited post-fire sediment monitoring. This paper also evaluates how post-fire forest management influences sediment transport. Studies have shown that different erosion control measures have varying levels of effectiveness, but more studies should be employed to better evaluate theses measures and new erosion control strategies should be developed. Salvage logging is a common post-fire practice and has the potential to enhance sediment transport through soil disturbance and greater reductions in ground cover. Post-fire sedimentation will continue to threaten important Sierra Nevada watersheds, and a greater emphasis needs to be placed on sediment monitoring and more effective forest management both before and after a fire.
Hacker, Kaitlyn, "Post-Fire Sedimentation and the Risk to Sierra Nevada Water Supply" (2015). Master's Projects. 149.