New geological research warns that the weight of New York City is causing the sinking of the Big Apple.
The city is dropping closer to the water at a rate of 1 to 2 millimeters a year, “with some areas subsiding much faster,” the study published in the journal Earth’s Future claims.
While that may not seem significant to untrained eyes, the gradual descent makes NYC extremely vulnerable to natural disasters, according to lead researcher and geologist Tom Parsons of the United States Geological Survey.
Lower Manhattan is particularly at risk, and there is a concern for both Brooklyn and Queens as well, according to the study.
“New York faces significant challenges from flood hazard; the threat of sea level rise is 3 to 4 times higher than the global average along the Atlantic coast of North America … A deeply concentrated population of 8.4 million people faces varying degrees of hazard from inundation in New York City,” Parsons and his team wrote in the new report.
New York has seen the effects of its sinking
The city has already seen these harsh effects starting more than a decade ago. “Two recent hurricanes caused casualties and heavy damage in New York City,” he wrote.
“In 2012, Hurricane Sandy forced seawater into the city, whereas heavy rainfall from Hurricane Ida in 2021 overwhelmed drainage systems because of heavy runoff within the mostly paved city.”
Parsons fears that the structural integrity of the city’s many buildings could be at risk in the future.
“The combination of tectonic and anthropogenic subsidence, sea level rise, and increasing hurricane intensity imply an accelerating problem along coastal and riverfront areas,” he wrote.
“Repeated exposure of building foundations to salt water can corrode reinforcing steel and chemically weaken concrete causing structural weakening.”
The researchers point out that the problem is due to a common natural phenomenon called subsidence, where heavy things, like buildings, gradually settle over time or when dramatic changes in the Earth result in them sinking into the ground.
This can be for various reasons, but sudden movements in soft sediment or heavy loads pushing down on soft deposits are prime examples.
The changes to the foundations of the city, home to over 8 million people, may pose a threat to its low-lying areas. Therefore, the researchers note, it is crucial to invest in developing mitigation strategies to address the increasing risk of flooding and rising sea levels.
However, constructing massive sea walls may not be the optimal solution. “The point of the paper is to raise awareness that every additional high-rise building constructed at coastal, river, or lakefront settings could contribute to future flood risk,” writes Parsons and his colleagues at the University of Rhode Island.