THE NORTH CAROLINA GEOLOGICAL SURVEY’S LANDSLIDE HAZARDS PROGRAM SUPPORTING WESTERN NORTH CAROLINA: CHALLENGES AND ADAPTATIONS RESULTING FROM THE SEPTEMBER 2024 EXTREME WEATHER EVENT CULMINATING WITH HURRICANE HELENE

The North Carolina Geological Survey’s (NCGS) Landslide Hazards Program (LHP) provides timely, unbiased, and accurate scientific information to emergency managers and the public. This information empowers informed decision-making regarding public safety, property protection, potential landslide loss reduction, and community resilience enhancement. We support western North Carolina’s rapidly growing population and development in addressing the challenges of living, working, and constructing in this mountainous region.

Our program encompasses landslide inventory and susceptibility mapping, landslide monitoring, landslide risk analysis, and technical assistance to emergency managers and the public in response to landslide events. We integrate landslide inventory data with historical and meteorological data to identify landslide triggering events and their correlations with geological factors, climate, weather patterns, forest cover/burned areas, and land use.

Across several days in late September 2024, western North Carolina experienced a catastrophic wind and record rainfall event culminating with Hurricane Helene which produced winds over 98 mph and rainfall approaching 30 inches in 72 hours in places. This event resulted in 23 landslide fatalities and approximately 80 flood fatalities, widespread and prolonged utility outages, and limited access for emergency response and populated areas due to road damage.

As of December 15th, 2024, the LHP had responded to 351 landslides at the request of emergency services and the public. The USGS Landslide Assessments, Situational Awareness, and Event Response Research Team (LASER) provided valuable situational awareness for emergency response and recovery operations and provided technical assistance through remote and field reconnaissance during initial response efforts until utilities were reestablished and access improved. The event’s material and recovery costs exceed several hundred million dollars.

This presentation introduces NCGS’s Landslide Hazards Program, the operational challenges posed by the September 24 - 28 weather event, and our ongoing adaptation efforts to support emergency services and the citizens of western North Carolina.