New Study Finds Buildings in New York City Causing the Metropolis to Sink and Increase Flood Risks

The weight of buildings in New York City is causing the metropolis to sink, increasing the risk of flooding, according to a new study.

City is sinking at an average rate of 1-2 millimeters a year, study finds published this month in the scientific journal Earth’s Future. Some areas are sinking much faster than average.

This phenomenon, known as subsidence, puts New York City at increased risk of flooding, a danger exacerbated by rising sea levels and intensifying storms.

“A highly concentrated population of 8.4 million people face varying degrees of flood risk in New York City,” the study warns.

The cumulative weight of buildings in New York City has been estimated at 3.7 billion kilograms. The five boroughs have just over a million buildings, the average structure of which weighs 3.4 million kilograms.

The researchers only calculated the weight of the buildings and their contents, without taking into account urban elements such as roads, bridges and subways, which means that the actual weight of the city is probably higher than the estimate.

The city’s skyscrapers exert the greatest downward pressure, but most of them are built on bedrock, while other structures rest on softer sand and clay.

New York City is built on water, with the densely populated central district of Manhattan located on a narrow island.

Other cities around the world are also sinking due to denser building patterns and face similar risks, say the study authors, who warn of “an accelerating problem along coastal and river areas”.

Natural processes, such as the effects of tectonic plates, also contribute to the drop.

The scientists reached their conclusions by calculating the weight of the city’s buildings, modeling the downward pressure they exert and measuring the difference in height using satellite data.

In 2012, Hurricane Sandy submerged part of New York City, causing power outages and lasting damage to infrastructure.

In 2021, Hurricane Ida caused massive flooding, claiming several lives.

The Atlantic coast of North America faces a threat of sea level rise 3 to 4 times higher than the global average, according to the study.