Cities along the eastern seaboard of the United States are sinking at an alarming rate, putting critical infrastructure and millions of people at risk, according to new research published this week.
Accelerating Land Subsidence
A study led by researchers at Virginia Tech shows that land subsidence is occurring faster than scientists previously thought in areas along the Atlantic Coast from Massachusetts down to Florida. Using advanced satellite imagery and geospatial analysis, the researchers found high rates of sinking across cities like Boston, New York, Norfolk, Charleston, Jacksonville, and Miami.
In some areas, the land is subsiding over 5 times faster than sea levels are rising. This means certain coastal regions are becoming increasingly prone to flooding during storms, high tides, and other events.
According to lead researcher Dr. Robert Jones:
“The rates of land subsidence we’re seeing along the East Coast are alarming. When you combine this subsidence with accelerating sea level rise driven by climate change, it magnifies the risk to people and infrastructure in coastal communities.”
The table below shows sinking rates vs sea level rise for some of the most affected cities:
| City | Land Subsidence Rate | Sea Level Rise Rate |
|---|---|---|
| Boston | 5.5 mm/year | 3.0 mm/year |
| Atlantic City | 4.6 mm/year | 3.2 mm/year |
| Norfolk | 7.0 mm/year | 4.5 mm/year |
| Miami Beach | 3.9 mm/year | 2.8 mm/year |
Threats to Infrastructure
The sinking land puts critical infrastructure like roads, rail lines, subway tunnels, utilities, data centers and more at growing risk of flooding during high tide events and storms.
For example, the study found that in Norfolk, VA home of the largest naval base in the world, land subsidence could put key military infrastructure underwater during regular flooding by 2030. Other East Coast cities face similar threats to roads, bridges, power plants, airports, and other vital systems.
“We can’t ignore the interaction between sinking land and rising seas,” said Dr. Jones. “If we don’t start managing this risk now, we’re putting trillions of dollars of infrastructure in jeopardy that communities rely on.”
Causes of Land Subsidence
There are several leading causes of land subsidence along the East Coast according to researchers:
- Groundwater extraction – Large scale pumping of groundwater can cause the ground to sink or compact over time
- Natural sediment compaction – In some areas, natural settling and compaction of soils leads to sinking
- Post-glacial rebound – The land readjusting after the retreating of ice sheets thousands of years ago
- Demographic shifts – More development and infrastructure itself presses down on the land
Scientists say contributing factors like groundwater pumping and compaction need to be better managed to slow subsidence rates. But some amount may be irreversible.
Actions to Protect Coastal Areas
In light of the sinking land crisis, experts recommend local and federal officials take actions such as:
- Improving monitoring of subsidence rates using satellite data
- Identifying and mapping high risk zones
- Implementing policies to limit groundwater extraction where possible
- Fortifying or relocating threatened infrastructure
- Boosting investments in natural buffers like wetlands and oyster reefs
- Pushing for zoning policies that discourage building in vulnerable areas
“This is a growing crisis, but if we act now, we can get ahead of some of the worst impacts,” said Dr. Susan Howard, a coastal resilience researcher. “Our modeling shows targeted adaptation investments today would save billions in avoided damages down the line.”
Outlook Going Forward
Researchers predict sinking land and rising seas will continue interacting to elevate flood risks along the East Coast over the next century and beyond. Groundwater pumping restrictions may slow land subsidence, but not stop it, and climate-driven sea level rise could accelerate.
This means coastal communities must learn to cope with increasing “nuisance” flooding during high tides and storms. Within 30 years, daily high tide flooding could inundate coastal zones even without storms.
Cities are working to update their flood protection infrastructure, but it may not keep pace with quickening environmental shifts. Difficult decisions around coastal development and property buyouts also loom according to policy experts.
“This is the new normal – preparing communities to live with water is as important as trying to wall it off entirely,” said Howard. “We have to bring all stakeholders together to plan for resilient adaptation.”
The intersecting phenomena of sinking land and rising seas presents complex challenges for East Coast cities already grappling with more frequent flooding. But researchers underscore that with ample preparation, targeted infrastructure updates, smart policy changes and advanced flood protection systems, coastal communities can develop tools to manage the growing crisis.
To err is human, but AI does it too. Whilst factual data is used in the production of these articles, the content is written entirely by AI. Double check any facts you intend to rely on with another source.
