Largest Earthquake in New York State History

Earthquakes occur in New York State on a regular basis, though few are considered major. The largest recorded earthquake in New York State happened between Massena, New York, and Cornwall, Ontario, on September 4, 1944.

Size

• The largest earthquake in New York State measured an intensity VIII on the Modified Mercalli Scale. Though not a major earthquake, an intensity VIII has potential for destruction. The earthquake was also felt in Delaware, Maryland, New Jersey, Pennsylvania, and all the New England states.

Effects

• In Massena about 90 percent of the chimneys were destroyed, and damage was done to masonry, plumbing and foundations. Ground cracking was noticed in nearby towns, and some reports had the wells in St. Lawrence County going dry. The damage estimate was 2 million between Massena and the nearest town, Cornwall, Ontario.

Potential

• The chance of a major earthquake is small in New York State because the area is not on a fault line, but the potential does exist for future moderate earthquakes. According to the New York State Geological Survey, the possibility of a damaging earthquake in New York State is higher in the New York City region and the Northern parts of the state.