Landslide Hazards
Publications
A 4000-year history of debris flows in north-central Washington State, U.S.A.: Preliminary results from trenching and surficial geologic mapping at the Pope Creek fan
Long-term records of the magnitude and frequency of debris flows on fans are rare, but such records provide critical information needed for debris-flow hazard and risk assessments. This study explores the history of debris flows on a fan with seasonally inhabited cabins at Pope Creek along the Entiat River about 48 km upstream from the town of...
Coe, Jeffrey A.; Bessette-Kirton, Erin; Slaughter, Stephen; Rengers, Francis K.; Contreras, Trevor A.; Michelson, Katherin A; Taylor, Emily; Kean, Jason W.; Jacobacci, Kara; Hanson, Molly A Exploring controls on debris-flow surge velocity and peak discharge at Chalk Cliffs, Colorado, USA
We present a series of debris-flow events and use combined sensor and video data to explore how sediment concentration and triggering rainfall intensity affect the velocity and discharge of debris-flow surges generated by surface-water runoff. We analyze an initial data set of 49 surges from four debris-flow events recorded by a monitoring system...
Smith, Joel B.; Kean, Jason W.; Coe, Jeffrey A. An evaluation of debris-flow runout model accuracy and complexity in Montecito, CA: Towards a framework for regional inundation-hazard forecasting
Numerous debris-flow inundation models have been applied retroactively to noteworthy events around the world. While such studies can be useful in identifying controlling factors, calibrating model parameters, and assessing future hazards in specific study areas, model parameters tailored to individual events can be difficult to apply regionally....
Bessette-Kirton, Erin; Kean, Jason W.; Coe, Jeffrey A.; Rengers, Francis K.; Staley, Dennis M. Real-time monitoring of debris-flow velocity and mass deformation from field experiments with high sample rate lidar and video
Debris flows evolve in both time and space in complex ways, commonly starting as coherent failures but then quickly developing structures such as roll waves and surges. This process is readily observed, but difficult to study or quantify because of the speed at which it occurs. Many methods for studying debris flows consist of point measurements (...
Rengers, Francis K.; Rapstine, Thomas; Allstadt, Kate E.; Olsen, Michael; Bunn, Michael; Iverson, Richard M.; Kean, Jason W.; Leshchinsky, Ben; Logan, Matthew; Sharifi-Mood, Mahyar; Obryk, Maciej; Smith, Joel B. Looking through the window of disturbance at post-wildfire debris-flow hazards
The extreme heat from wildfire alters soil properties and incinerates vegetation, leading to changes in infiltration capacity, ground cover, soil erodibility, and rainfall interception. These changes promote increases in runoff and sediment transport that increase the likelihood of runoff-generated debris flows. Over a period of several years,...
McGuire, Luke; Rengers, Francis K.; Kean, Jason W.; Staley, Dennis M.; Tang, Hui; Youberg, Ann Topographic change detection at Chalk Cliffs, Colorado, USA, using Airborne LiDAR and UAS-based Structure-from-Motion photogrammetry
The Chalk Cliffs debris-flow site is a small headwater catchment incised into highly fractured and hydrothermally altered quartz monzonite in a semi-arid climate. Over half of the extremely steep basin is exposed bedrock. Debris flows occur multiple times per year in response to rainstorm events, typically during the summer monsoon season. The...
Barnhart, Katherine R; Rengers, Francis K.; Ghent Jessica N; Tucker, Gregory E.; Coe, Jeffrey A.; Kean, Jason W.; Smith, Joel B.; Staley, Dennis M.; Kleiber, William; Wiens, Ashton M Post-fire rockfall and debris-flow hazard zonation in the Eagle Creek Fire burn area, Columbia River Gorge, Oregon: a tool for emergency managers and first responders
The Eagle Creek Fire engulfed 48,832 acres (196 km2) within the Columbia River Gorge, Oregon beginning September 2nd and was 100% contained by November 30th, 2017. The Columbia River Gorge area is steep and heavily forested characterized by cliffs and flanking talus slopes, receiving > 100 inches (> 254 cm) of precipitation annually. The...
Calhoun, Nancy C.; Burns, William J.; Hayduk, S.H.; Staley, Dennis M.; Kean, Jason W. Taking the pulse of debris flows: Extracting debris-flow dynamics from good vibrations in southern California and central Colorado
The destructive nature of debris flows makes it difficult to quantify flow dynamics with direct instrumentation. For this reason, seismic sensors placed safely away from the flow path are often used to identify the timing and speed of debris flows. While seismic sensors have proven to be a valuable tool for event detection and early warning, their...
Michel, A.; Kean, Jason W.; Smith, Joel B.; Allstadt, Kate E.; Coe, Jeffrey A. Inundation, flow dynamics, and damage in the 9 January 2018 Montecito Debris-Flow Event, California, USA: Opportunities and challenges for post-wildfire risk assessment
Shortly before the beginning of the winter rainy season, one of the largest fires in California history (Thomas Fire) substantially increased the susceptibility of steep slopes in Santa Barbara and Ventura Counties to debris flows. On January 9, 2018, before the fire was fully contained, an intense burst of rain fell on the portion of the burn...
Kean, Jason W.; Staley, Dennis M.; Lancaster, Jeremy T.; Rengers, Francis K.; Swanson, Brian J.; Coe, Jeffrey A.; Hernandez, Janis .; Sigman, Aaron; Allstadt, Kate E.; Lindsay, Donald N. Constraining parameter uncertainty in modeling debris-flow initiation during the September 2013 Colorado Front Range storm
The occurrence of debris flows during the September 2013 northern Colorado floods took the emergency management community by surprise. The September 2013 debris flows in the Colorado Front Range initiated from shallow landslides in colluvium. Most occurred on south- and east-facing slopes on the walls of steep canyons in crystalline rocks and on...
Baum, Rex L.; Scheevel, C.R.; Jones, Eric S. Wildfire as a catalyst for hydrologic and geomorphic change
Wildfire has been a constant presence on the Earth since at least the Silurian period, and is a landscape-scale catalyst that results in a step-change perturbation for hydrologic systems, which ripples across burned terrain, shaping the geomorphic legacy of watersheds. Specifically, wildfire alters two key landscape properties: (1) overland flow,...
Rengers, Francis K. Factors controlling landslide frequency-area distributions
A power‐law relation for the frequency–area distribution (FAD) of medium and large landslides (e.g. tens to millions of square meters) has been observed by numerous authors. But the FAD of small landslides diverges from the power‐law distribution, with a rollover point below which frequencies decrease for smaller landslides. Some studies conclude...
Tanyaş, Hakan; van Westen, Cees J.; Allstadt, Kate E.; Jibson, Randall W.