Jakarta, Indonesia, is the world’s fastest-sinking major city, with parts of its northern coast dropping as much as 20 centimeters (about 8 inches) per year. The problem is so severe that Indonesia is building an entirely new capital city on the island of Borneo to eventually replace Jakarta as the seat of government. But Jakarta isn’t alone. Dozens of coastal cities across the globe are sinking, many of them faster than the ocean is rising around them.
Why Jakarta Sinks Faster Than Anywhere Else
North Jakarta sits on swampy, low-lying ground near the Java Sea, and millions of residents and businesses pump groundwater from wells beneath the city. As underground aquifers are drained, the soil above compacts and the surface drops. The fastest subsidence, around 20 cm per year, is concentrated in the northwest, an area dominated by housing and dense settlements rather than commercial or industrial zones. Roughly 40 percent of the city already sits below sea level, and without intervention, large sections could be permanently submerged by mid-century.
The Indonesian government’s response has been dramatic: relocating the capital to a new city called Nusantara, carved out of forest in East Kalimantan on the island of Borneo. Around 4,000 civil servants are expected to move there in 2026, with legislative and judicial complexes targeted for completion by 2028. The project is meant to relieve pressure on Jakarta, though the old city will remain Indonesia’s commercial hub and its sinking will continue unless groundwater extraction slows significantly.
Ho Chi Minh City and Southeast Asia’s Soft Ground
Ho Chi Minh City, Vietnam’s largest metropolis, is one of the five fastest-sinking cities in the world. The city subsides by 10 to 15 mm on average each year, but neighborhoods with dense commercial buildings or proximity to rivers and canals sink far more quickly, at rates of 6 to 8 cm per year. A survey by the Japan International Cooperation Agency found subsidence of 2 to 5 cm annually across much of the city, jumping to 7 to 8 cm in heavily built-up areas.
The scale of the problem is enormous. As of 2019, nearly 15,000 hectares of the city were classified as rapidly sinking (more than 15 mm per year), and another 22,000 hectares were sinking at 10 to 15 mm per year. By recent counts, the total subsidence-affected area has reached roughly 7,200 hectares of the most critical zones near rivers and canals. The causes mirror Jakarta’s: heavy groundwater pumping, the sheer weight of new construction on soft delta soils, and rapid urbanization that paves over ground that once absorbed floodwater.
Bangkok, Thailand, faces a similar situation. Built on a thick layer of marine clay, the city sits barely 1 to 2 meters above sea level in many neighborhoods. Decades of groundwater extraction caused dramatic sinking in the late 20th century. Regulations introduced in the 2000s slowed the rate considerably, but the city remains extremely vulnerable to flooding because it has so little elevation to spare.
Venice: A Different Kind of Sinking
Venice is probably the most famous sinking city in the world, though its situation is quite different from the Asian megacities. The city sinks slowly, just 1 to 2 mm per year from natural geological settling, and the bigger threat comes from rising tides in the Adriatic Sea. Over the past 60 years, tides exceeding 1.1 meters have become significantly more frequent, flooding the historic city center during events Venetians call “acqua alta.”
Italy’s answer was MOSE, a system of 78 mobile barriers that rise from the seabed to block incoming tides. Operational since October 2020, MOSE has proven very effective at keeping water levels in the lagoon below the critical 110 cm mark. In its most recent autumn-to-summer cycle, the barriers were raised 31 times, up from fewer than 20 activations per cycle in prior years. That increase reflects both worsening conditions and growing confidence in the system. One concern: salt marshes in the lagoon sit lower than 70 cm and still flood regularly even when MOSE activates, and reduced sediment flow could gradually reshape the lagoon ecosystem.
African and Middle Eastern Coasts at Risk
Lagos, Nigeria, is sinking at more than 10 mm per year, over twice the global average for coastal cities. Alexandria, Egypt, and Douala, Cameroon, are subsiding at similar rates. In Lagos, a combination of groundwater extraction, poorly regulated construction on reclaimed land, and intense coastal erosion compounds the problem. The city’s population is projected to exceed 20 million in the coming decades, meaning more weight on unstable ground, more wells pumping water, and more people living in flood-prone areas. Unlike Venice or Jakarta, most of these African cities lack the funding or infrastructure for large-scale flood defenses.
Sinking Cities in the United States
Several American cities are sinking too, driven by a mix of groundwater and fossil fuel extraction, geological processes, and heavy infrastructure. In the Houston-Galveston area of Texas, long-term groundwater mining and oil and gas extraction have produced subsidence rates of up to 5 cm per year in certain spots. Across Texas more broadly, cities including Houston, Fort Worth, and Dallas show the highest measured subsidence rates in the country, averaging more than 4 mm per year.
New Orleans faces a double threat. The Mississippi Delta beneath the city is subsiding at more than 1 cm per year, a process worsened by the network of levees and dams upstream that prevent fresh sediment from replenishing the sinking land. The Chesapeake Bay region on the East Coast experiences about 2 mm per year of subsidence from a completely different cause: the slow rebound of Earth’s crust after the last ice age, a process called glacial isostatic adjustment. That may sound small, but it roughly doubles the rate of relative sea-level rise that communities around the bay experience.
Why Land Sinking Matters More Than Sea-Level Rise
Global sea levels are rising at roughly 3.5 mm per year. That’s a serious long-term problem. But in many coastal cities, the ground is dropping 5 to 50 times faster than the ocean is climbing. The practical effect is the same (water creeps higher relative to streets and buildings) but the cause is largely local and, in theory, preventable. As NASA’s sea-level monitoring program notes, subsidence in coastal areas directly translates to higher relative sea levels and increased flood risk, often dwarfing the contribution of ocean warming and ice melt.
The human stakes are staggering. Under a moderate climate scenario, sea levels projected for 2050 threaten land currently home to about 150 million people worldwide, putting it permanently below the high-tide line. That’s triple previous estimates, largely because older elevation data underestimated how low many coastal cities actually sit. The difference between those old and new numbers comes down to accounting for subsidence: the ground wasn’t where we thought it was.
Stopping groundwater extraction is the single most effective intervention for slowing subsidence. Tokyo demonstrated this decades ago, halting severe sinking by strictly regulating well water use in the 1970s. Bangkok followed with partial success. Jakarta and Ho Chi Minh City are attempting similar policies, but enforcement is difficult when millions of residents depend on wells because piped water systems can’t keep up with population growth. The cities that solve their water infrastructure problem will slow their sinking. The ones that don’t will face an increasingly permanent relationship with the sea.