All Largest US Cities Are Sinking Threatening Infrastructure Stability

A groundbreaking study published in Nature Cities reveals that all 28 of the United States’ largest cities, each with populations exceeding 600,000, are experiencing land subsidence to varying degrees. This widespread sinking is not limited to coastal areas but extends to inland cities such as Denver, Oklahoma City, and Fort Worth. The research, led by Leonard Ohenhen of Columbia Climate School, utilized satellite data to map vertical land movements in systematic 90-square-foot grids, uncovering a pervasive trend that threatens urban infrastructure.

The primary driver behind this subsidence is groundwater extraction, responsible for approximately 80% of the observed sinking. When water is removed from underground aquifers, the porous rock layers collapse, causing the land above to drop. This effect is exacerbated by increasing urban populations, rising water demands, and climate-induced droughts, which strain water resources further. Additionally, some regions are still adjusting from geological changes dating back to the last ice age, and the immense weight of urban infrastructure may also contribute to land movement.

Houston emerges as the fastest sinking city, with over 40% of its land subsiding more than 5 millimeters annually, and 12% sinking at twice that rate. Other major cities including New York, Las Vegas, Washington D.C., and San Francisco also contain zones of rapid subsidence. This uneven sinking, known as differential motion, can cause structural stresses such as building tilting, posing significant risks to urban infrastructure.

While only about 1% of the affected areas experience differential motion severe enough to impact infrastructure, these zones are typically the most urbanized, encompassing roughly 29,000 buildings nationwide. Cities like San Antonio, Austin, Fort Worth, and Memphis have notable proportions of buildings at high risk. The study emphasizes that even minor land motion changes can damage infrastructure, unlike flood-related subsidence hazards that require critical elevation thresholds to be crossed.

The implications of this research are profound for urban planning and infrastructure management. As cities continue to expand into subsiding regions, the cumulative stress on buildings, roads, and utilities will increase, potentially surpassing safety limits. Moreover, sinking land is more vulnerable to flooding, compounding risks from climate change. The authors advocate for proactive mitigation strategies including land raising, retrofitting existing structures, and updating building codes to enhance resilience.

This study underscores the critical need for integrating advanced geospatial monitoring and data-driven decision-making in urban development. By leveraging satellite data and comprehensive risk assessments, policymakers and engineers can better understand subsidence patterns and implement targeted interventions. The research serves as a call to action to move beyond recognizing subsidence as a problem and towards developing adaptive, solution-oriented approaches that safeguard the future of America’s cities.