The U.S. Geological Survey today unveiled a new web-based interactive map that marks an important step toward mapping areas that could be at higher risk for future landslides. In collaboration with state geological surveys and other federal agencies, USGS has compiled much of the existing landslide data into a searchable, web-based interactive map called the U.S. Landslide Inventory Map.
“Although landslides occur in every state, our understanding of landslide hazards at the national scale is limited because landslide information across the U.S. is incomplete, varies in quality, accessibility and extent and what is known is not collected in a central location,” said Jonathan Godt, USGS program coordinator for Landslide Hazards.
Until now, no federal agency sought to undertake the monumental task of systematically cataloging landslide occurrence across the U.S. Existing digital data on landslide occurrence are held by a range of federal, state, and local government agencies, and no central point of access has previously been available.
Where data are available, the searchable map provides links to original digital geospatial files for further information. The current landslide inventory is not comprehensive as further mapping is needed in many parts of the country. For example, absence or sparseness of mapped landslides in areas of steep topography points to locations where the knowledge of landslide history and activity is likely poor. Periodic updates of the database are planned as new or improved data become available, increasing the usefulness of the product.
“The database provides centralized access to information about landslide occurrence and a starting point for the public, land managers, emergency planners and researchers interested in landslide hazards” said Godt.
Alaska, the U.S. West Coast and Rocky Mountain states, and Puerto Rico experience numerous landslides each year and other parts of the U.S., including the Midwest, Appalachia and Northeast are also often impacted by landslides.
Landslides have had disastrous impacts to communities in recent years, for example in March 2014, a large landslide near Oso, Washington, killed 43 people and caused millions of dollars in damage to property and infrastructure. In January 2018, debris flows originating from hillsides burned by the Thomas Fire in Montecito, California, killed 23 people, damaged more than 400 homes, and impacted businesses and infrastructure.