Major U.S. Cities Are Sinking — Groundwater Depletion Identified as Key Cause

A recent study has revealed that many of the largest cities in the United States are gradually sinking, with the primary cause in most cases linked to the overextraction of groundwater. According to researchers, the ground beneath all 28 major metropolitan areas surveyed is subsiding at rates ranging from two to ten millimeters per year.

The findings come from a research team at Columbia University in New York, as reported by the science outlet Scinexx. Using high-resolution radar satellite data collected between 2015 and 2021, scientists assessed ground movement across U.S. cities with populations exceeding 600,000 residents. They then compared this data with groundwater usage records to identify correlations.

Houston Faces the Most Severe Subsidence

Among all cities analyzed, Houston, Texas, stands out as the most affected. The ground there is sinking by an average of five to ten millimeters annually, with some isolated areas subsiding as much as five centimeters each year. Other major cities showing significant subsidence include parts of New York City near LaGuardia Airport, Washington D.C., Las Vegas, Los Angeles, and San Francisco.

Groundwater Withdrawal Creates Underground Voids

In roughly 80 percent of the cases studied, the researchers attributed the subsidence to excessive groundwater extraction. When too much water is pumped from underground aquifers, it leaves behind tiny voids that eventually collapse, leading to gradual ground sinking. In Texas, the issue is further intensified by oil and gas extraction, which has similar geological consequences. In certain coastal cities, however, natural geological shifts — rather than human activity — appear to be the primary factor.

Structural Damage and Flooding Among the Risks

The research team warns that ground subsidence could result in serious consequences, especially for infrastructure. Uneven sinking — and, in some cases, sudden re-elevation caused by rapid replenishment of groundwater through river inflows — can create stress on buildings, roads, and bridges, leading to visible cracks and structural weaknesses. In extreme scenarios, key infrastructure could be rendered severely damaged or entirely unusable.

While only around one percent of the studied urban areas are at high risk for such extreme damage, these zones are often located in central, densely populated parts of cities — amplifying the potential impact on residents and urban systems.

The study underscores the urgency of managing groundwater resources more sustainably, especially as many cities continue to grow and face increasing pressure from climate change and urban development.