Monitoring and Response Tools for Post-Wildfire Debris Flow Management

About the Program

Category: Information Technology (Best in Category)

Year: 2019

Riverside County, California experienced widespread wildfires in 2018 which left more than 36,000 acres burned. Burn areas have high potential for mud and/or debris flows caused by unstable slopes which can be triggered by short duration high intensity storms. Spurred by the risks associated with post-wildfire storms, the Riverside County Flood Control and Water Conservation District (District) has been using the newest technology to improve response to life-threatening flows. The District’s surveyors use direct georeferencing drone technology which can map otherwise unreachable areas. Drone mapping and custom LiDAR was used to develop debris flow risk areas, prepare evacuation maps, and help develop the Watershed Emergency Response Team report for communities downstream of the fire. Rainfall and depth monitoring gauges and cameras were installed in high risk areas to give emergency managers real-time situational awareness. This data is presented in a web-based dashboard for emergency response personnel that displays real-time rainfall data across the burn scar and notifies the user when rainfall intensities exceed the predicted debris-producing thresholds. It also provides live webcam feeds and time lapse images of high risk areas. The District leveraged existing field communication tools and implemented data collection technologies for vital real-time updates from District staff in the field during storm events. This information helps our operations and maintenance personnel prioritize facilities that need attention. Within hours after storms, the District’s drone can map areas where debris and mud flows have occurred. California Geological Survey is using this data to advance the science of post-wildfire response with respect to debris flows by comparing the information the District gathered on pre- and post-wildfire conditions to use in the future throughout the state. Data gathered by the District has also been shared with other public agencies, including the county, state, and cities, to aid in emergency response.