Across the world, many cities are slowly sinking. Most are on the coast, including tropical megacities like Jakarta in Indonesia or Manila in the Philippines, or places like New Orleans, Vancouver or much of the Netherlands. Other sinking cities, like Mexico City and many of those in China, can be well inland. Yet this still remains a widely overlooked hazard.
In my three decades assessing this topic, I have reviewed evidence of subsidence in cities around the world. The problem is especially significant in Asia, where about 60% of the world’s population lives and the cities are growing rapidly. However, some cities have also shown there are things that can be done to stop subsidence.
The problem is illustrated by a recent study by researchers in China which found that more than a third of the country’s urban population – some 270 million people – live in sinking cities.
