Researchers at the University of Washington have released the first systematic, nationwide accounting of landslide risks in the United States, revealing that roughly 6.5 million people live in vulnerable regions. The new database maps building-level susceptibility across 128 million structures to help communities prioritize disaster mitigation.
Landslides cause an estimated $3-6 billion in damage and multiple fatalities annually in the United States. Those losses could escalate as housing demand drives development into hazard-prone terrain and climate change increases the frequency of heavy rains that trigger slope failures. Despite the scale of the threat, the country has lacked a systematic nationwide database until now.
Building the Landslide Exposure Database
Researchers at the University of Washington constructed the new resource, known as the Landslide Exposure Database, by blending massive geospatial and demographic repositories. To build the system, the team utilized a terrain and landslide susceptibility map from the United States Geological Survey alongside building footprints from the Overture Maps Foundation and occupancy records from the Army Corps of Engineers.
The project went beyond simple data merging. Lead author Daniel Acosta-Reyes noted that the core challenge involved curating rich national information into an accessible tool for the public and policymakers. The finished database rates 128 million buildings nationwide for landslide susceptibility and pairs that physical data with Census Bureau metrics covering income, vehicle access, disability status, and housing conditions.
Where Vulnerable Populations Are Concentrated
The analysis shows that while roughly 20% of the land area in the United States is prone to landslides, those zones contain about 2% of the total population, or approximately 6.5 million vulnerable residents. Geographic concentration is stark: 80% of those high-risk individuals live either along the West Coast or in Appalachia, with West Virginia holding the largest share of at-risk residents in the nation.
Wartman added that the localized nature of the hazard makes it more practical and affordable for state and local governments to address. The data also highlights a sharp socioeconomic divide between urban and rural populations living in danger zones.
The Urban-Rural Divide in Hazard Exposure
Socioeconomic vulnerability to slope failures shifts dramatically depending on geography. In rural parts of the country, residents in landslide zones tend to face greater economic constraints, have fewer resources to prepare for or recover from disasters, and live in structures farther away from emergency services.
In urban settings, the pattern reverses entirely. City properties prone to landslides are often highly valued hillside neighborhoods featuring scenic views, meaning the exposed residents typically possess greater financial resilience and recovery capacity.
Tools for Public Access and Future Mitigation
The research team published their findings on July 29 in Earth’s Future and made the database publicly available alongside user-friendly tools. Nonscientists can explore census tracts, population numbers, exposure percentages, and poverty indicators using a web-based browser called Hazmapper. Individuals can also check the susceptibility of any address nationwide by downloading Google Earth Pro.
Because of regional differences, the researchers advise against uniform federal policies, suggesting instead that mitigation must fit local realities. Appalachian strategies might focus on widespread early warning systems, while West Coast cities like Seattle and San Francisco may rely on stricter building regulations for hazardous slopes. Regulators and emergency managers now have an empirical foundation to distribute education and mitigation resources efficiently.
Keep reading
