The area burned by wildfire in the American West has been increasing since the peak of the effective fire-suppression era in the mid-20th century. With wildfire area and severity projected to continue rising, post-wildfire erosion is also expected to increase in most western watersheds. This eroded sediment will eventually make its way into rivers, where it can be transported downstream. Understanding these cascades of sediment through watersheds is a challenge and requires spanning the disciplines of hillslope and fluvial geomorphology.
Working with Drs. Jon Czuba at Virginia Tech & Patrick Belmont at Utah State, we have developed a novel watershed-scale modeling framework that links post-wildfire debris flow generation models with state-of-the-art sediment routing models. In our first application of this new geomorphic modeling framework, we evaluated post-wildfire sediment dynamics following the Twitchell Canyon Fire (2010) in the Tushar Mountains of Utah (Murphy et al., ESPL, 2019).
Motivated to understand the risks that post-wildfire sediment may pose to downstream water infrastructure, I am now leading an NSF-funded project (PIs: Murphy, Belmont & Czuba) focused on further developing this model and integrating its components into open-source and high-performance computing frameworks (i.e., Landlab). As we seek to better understand post-wildfire sediment cascades, we will be applying this framework to evaluate the vulnerability of water supply reservoirs to post-wildfire sedimentation throughout the state of Utah.