A first-of-its-kind comprehensive federal landslide risk map marks the White House as a location with a history of unstable earth that could be the site of future trouble.
“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. The USGS notes that, while the project is a huge step forward in mapping out the risk, data is incomplete in some parts of the country.
Still, Godt said, the mapping provides “a starting point for the public, land managers, emergency planners and researchers interested in landslide hazards.”
One starting point is 1600 Pennsylvania Ave., which the inventory marks as “confident consequential landslide at this location.”
The reason for the inclusion dates back to May 2018, when a sinkhole opened on the White House’s north lawn. The ground was saturated from heavy spring rain at the time, and recent water main installation was also pegged as a possible factor.
“We do not believe it poses any risk to the White House or is representative of a larger problem,” a National Park Service spokesperson said at the time, noting they would further explore the sinkhole.
“On Friday, May 25, crews excavated an area around the small sinkhole on the north White House grounds. We found an underground void about six to eight inches in diameter, which was likely caused by recent heavy rains that eroded the soil,” NPS spokeswoman Jenny Anzelmo-Sarles later said in a statement. “In the coming days, we will plug the void with concrete, fill in the excavated area with gravel and soil, and resod. The excavation confirmed that the sinkhole, which did not grow larger since it was first noticed on May 20, does not pose a risk to the White House.”
After exploratory excavation, the sinkhole was covered up.
This January, a sinkhole opened up a block from the White House in the middle of 17th Street NW. The cave-in crushed an underground sewer line and damaged two power lines.