Widespread landslides across southern Appalachia following Hurricane Helene: U.S. Geological Survey's emergency response, initial observations, and historical context
Between the 23rd-27th of September 2024, antecedent rain followed by Hurricane Helene produced widespread flooding and landsliding across southern Appalachia, resulting in one of the most damaging weather events in the region’s history. The back-to-back storms produced observed rainfall accumulations of up to 33 inches and hurricane-force winds gusting over 120 miles per hour in western North Carolina, eastern Tennessee, and southwestern Virginia. The resulting regional flooding, landslides, and tree blowdown caused over 100 fatalities, damaged or destroyed critical infrastructure and thousands of structures, and severed connectivity across the region. Together with state, federal, and local partners, the U.S. Geological Survey activated their landslide emergency response team to coordinate rapid remote, aerial, and field mapping of thousands of landslides and their impacts. They also produced preliminary hazard models and assessments, daily situational reports, and educational and outreach materials. These efforts provided timely information to aid emergency response, and the initial observations highlight the destructive role of landslides and debris flows in this historic event. This presentation will describe the initial observations, including how landslides mobilized woody debris and delivered massive sediment loads to channels, streams, and reservoirs, contributing to the flood risk in the region.
Presenters:
- Benjamin B. Mirus, Supervisory Research Geologist, U.S. Geological Survey, Geologic Hazards Science Center
Link to Materials and Other Resources:
Date: June 25, 2025