Workers stood along the top of Banqiao Dam, some 150 feet above the valley’s floor, desperately trying to repair its crest as rain from Typhoon Nina fell for a third straight day. After battering Taiwan, the storm had moved inland where it was expected to dissipate, but Nina turned north instead, reaching the Huai River basin on Aug. 5, 1975, where a cold front blocked its progression. Parked in place, the typhoon generated more than a year’s worth of rain in 24 hours.

By the time night fell on Aug. 8, as many as 65 area dams had collapsed. But despite the fact that water levels at the Banqiao Dam had far exceeded a safe capacity, and a number of sluice gates for controlling water flow were clogged with silt, authorities felt confident they’d skirt disaster. After all, the Soviet-designed dam had been built to survive a typhoon — a once-every-1,000-year occurrence that could dump 11 inches of rain per day. Unfortunately, Typhoon Nina would prove to be a once-every-2,000-year storm, bearing down with enough force to cause the world’s deadliest infrastructure failure ever.



Chen Xing, one of China’s foremost hydrologists, had followed the construction of Banqiao in 1952 with concern. Chairman Mao Zedong, eager to modernize the country, ordered hundreds of dams built, which put people to work, provided electricity and tamed rivers as part of his brutal Great Leap Forward. After swimming across the Yangtze River in 1958, Mao penned a poem about his obsession with dams: “Great plans are being made/ Walls of stone will stand upstream to the west …The mountain goddess if she is still there/ Will marvel at a world so changed.” Decades later, ignoring warnings from scientists and environmentalists, the Chinese government initiated construction of the Three Gorges Dam — the world’s largest power station — on the Yangtze.

The dam breach caused more than 85,000 people to die instantly.

Xing was one among many who feared the country was building too fast and too recklessly. When he designed the Suya Lake Reservoir in 1958 — at the time the largest reservoir in Asia — he was admonished for trying to add more sluice gates. Labeled a “right-wing opportunist,” he was eventually fired for being a vocal critic.

According to an account of the Banqiao Dam by a Chinese journalist writing under the pseudonym Yi Si, on Aug. 8, as workers stared curiously at the retreating water level of the reservoir, a voice in the dark called out: “The River Dragon has come!” And suddenly the dam ruptured, unleashing 600 billion liters of water and destroying an entire village. By Aug. 17, reports Si, 1.1 million people remained trapped by flooding with 50 to 60 percent of food air-dropped into the area floating in the murky waters. It would take weeks for the waters to drain, revealing bloated corpses dotting the landscape in the late summer sun.

The government kept news of the disaster from being broadcast nationally, and there hadn’t been any international observers present. But when China’s Ministry of Water Resources and Electric Power released a study in July 1989, it reported that the dam breach caused more than 85,000 people to die instantly. Two years earlier, “On Macro-Decision Making in the Three Gorges Project,” a study conducted by eight Chinese water science experts who probably had access to censored government reports, estimated the number of total dead — from flooding and the resulting epidemics and famine — at 230,000.

Although the disaster is thought to be the deadliest of its kind anywhere in the world, it’s not common knowledge even inside China. When the dam broke, the Communist Party’s control of the media was near absolute, explains David Bandurski of the University of Hong Kong’s China Media Project. “Generally speaking, disasters of all forms, whether primarily natural in cause or human in cause, have been viewed by China’s leaders as highly sensitive,” he says, with the government loathe to concede culpability.

In the wake of the calamity, however, there are signs of change. In a country of 87,000 reservoirs, most built during a period of questionable construction standards, the government has taken a more aggressive stance on supervision and monitoring for needed repairs. In 2005, at a seminar in Beijing, officials and scientists agreed to open the Banqiao Dam failure for public debate and declared that casualty figures were no longer state secrets. And yet, explains Bandurski, when a Shanghai-based media company recently produced an in-depth feature critical of the Three Gorges Dam, the story was removed from the internet within hours.

From Laos to Colombia, ambitious dam projects are back in fashion. “There’s a massive dam building spree happening worldwide, and China has its hands in many of them,” says William Laurance, an environmental science professor at James Cook University. Around the globe, he estimates that 4,000 major hydroelectric dams are either in the planning or construction phase in what he terms a “hydroproject tsunami.” What scares Laurance and others who track these projects? The sense that China remains relatively less risk averse to potential failures.

In July of 2018 a Korean-built dam collapsed on the border of Laos and Cambodia, killing what may have been hundreds … although reliable numbers are hard to come from the Lao government. China’s People’s Liberation Army quickly mobilized to provide relief. While some saw simply aid to an ally, other analysts guessed at political motives: China is building dams up and down the Mekong too.

Correction: The original version of this story incorrectly referred to Mao Zedong on the second reference as Zedong, rather than Mao.