Groundwater Extraction Is Sinking Major Cities
From New York to Los Angeles, cities in the United States are sinking. According to a recent study, which looked at the 28 most populous cities, all were sinking to some degree. The authors of the study point to massive ongoing groundwater extraction as the most common cause.
The study, conducted by Columbia Climate School, used satellite data to map out land movements. In 25 of the 28 cities studied, two-thirds or more of their area is sinking. By taking these measurements and correlating the data to land movements, the researchers determined that 80% of the sinkage was caused by groundwater removal for human use.
Perhaps unsurprisingly, Houston was identified as the fastest-sinking city. Given Texas’ continuous struggle against droughts, as well as oil and gas extraction, the state has been known to face water issues.
Among other causes for the sinking cities included natural forces, and even the weight of buildings. In New York City particularly, the 1.1 million buildings are pressing down on the land and contributing to sea-level rise.
Besides increased flood risk, this sinking could prove problematic for U.S. infrastructure. “Even slight downward shifts in land can significantly compromise the structural integrity of buildings, roads, bridges, and railways over time,” said Leonard Ohenhen, lead author of the study.
With this information in mind, the authors of the study encouraged cities to focus on finding solutions. They point to land raising, enhanced drainage systems, and green infrastructure as potential mitigation. “As opposed to just saying it’s a problem, we can respond, address, mitigate, adapt,” Ohenhen said.
As American cities continue to grapple with the dual threats of sinking land and rising seas, the findings of this study offer not just a warning, but a call to action. From improved water management to investment in resilient infrastructure, there is still hope for stability for these sinking cities.