The National Geodetic Survey has found no significant changes in the ground beneath the Washington Monument as a result of last year’s earthquake.
The survey announced Tuesday that a study last March and April of sites around the Mall, the White House, the Capitol, and Union Station found slight changes in the ground beneath those places but they were all normal.
The survey, done at the request of the National Park service, showed that the part of the Mall built on dredged river fill had only sunk an inch since 1926, and the Monument has sunk only 2.2 inches since 1901.
The region and its monuments were jolted by a 5.8 magnitude earthquake last August 23. The 91,000-ton Washington Monument suffered extensive damage and has been closed for repairs ever since.
“We were very, very glad to report to the park service that we couldn’t detect” anything out of the ordinary, said Dave Doyle, the agency’s chief geodetic surveyor. The park service was worried about underground “liquifaction.” Doyle said there had been hardly any.