The Disaster China Tried to Bury (Deadly Subway Flood)

Añadido: 2026-06-10

[00:00:00]I don't know if this is my last post.

[00:00:02]Ding Xiao Peng spoke those words around 6:00 in the evening on July 20th, 2021, as the water inside her subway train rose to her chest, while the people around her seemed to have given up. But why couldn't they escape in time? To understand that, we need to start with the city. Zhengzhou is the capital of Henan, a city of 12.6 million people on the Yellow River. It is inland, not coastal, and historically dry, with an annual average of about 25 [music] in of rain. In 2016, it had been chosen as one of China's flagship sponge cities, a national pilot meant to make urban areas absorb and survive heavy rainfall. Metro Line 5, the city's only loop and the busiest line in the network, had opened in 2019. On a normal weekday, it carried roughly 500,000 commuters around the city. On July 20th, 2021, Ding Xiao Peng was one of them.

[00:01:02]Water that reached the train [music] did not come from the rain alone. It came through the perimeter wall of a parking lot, a wall that had been built to hold back [music] floodwater, and it failed at every level it was supposed to work on. The parking lot itself sat below street level, with the tunnels of Metro Line 5 running directly out of it. When the wall gave way, the water that poured into [music] the parking lot kept going down through the tunnels until it reached the train. To understand why the wall failed, you have to go back to 2017, [music] when Line 5 was still under construction. Zhengzhou Metro Group asked the designers to move the parking lot about 100 ft east and sink it more than 6 ft below the streets above. The change freed up adjacent land [music] for property development. It also meant the depot was now lower than everything around it, with one wall standing between it and any rainwater that came its way. The flood plan for that wall assumed that a once-in-a-century flood would reach it at [music] a depth of less than 10 in.

[00:02:04]The actual figure required by code was more than double that. The wall was designed for half the water it was supposed to hold back. Along the western edge of the parking lot, more than 40% [music] of that wall was not really a wall at all. Long stretches of the planned perimeter had been replaced [music] with temporary construction barriers, the kind used to fence off the building site. They had almost no water-retaining function. Outside the parking lot, the drainage [music] was already failing. A 1,000-ft strip of dumped soil from a nearby road project was sitting on top of the open ditch that was supposed to carry stormwater away. When the storm came, water that should have flowed away from the wall would flow toward it instead. In May 2019, Line 5 opened.

[00:02:52]Half a million people a day began riding the line above the wall. By the start of July 2021, no one above ground had any reason to think about the wall behind Wulanchao, but the forecasts arriving in the city's emergency management office were about to make it matter. In the second week of July, the China Meteorological Administration's main weather model began projecting an extreme rainfall event over Henan. More than 8 in of rain per day, 3 days [music] running. The first red rain storm warning was issued just before 10:00 p.m. on Monday, July 19th. Four more would follow over the next 18 hours. Red is the highest warning the Chinese weather service issues. The weekend before, Saturday the 17th and Sunday the 18th, became the most scrutinized days. During those 2 days, Zhengzhou's party secretary and mayor did not organize analysis, mobilization, deployment, or supervision for flood prevention. Only one vice mayor inspected anything at all, and what he inspected was road improvements and known ponding spots. The Metro group made no special preparation. Trains were scheduled to run as normal on Monday and Tuesday. Then, on Tuesday morning, July 20th, 2021, the rain that the forecasts had described in advance began to fall on Zhengzhou. At 8:00 a.m., the city government issued a notice. It did not order what the situation required, closing schools, canceling gatherings, and shutting businesses across the city.

[00:04:27]Instead, it only suggested that workplaces consider flexible hours. By the time most people read it, they were already at work. At 10:30 a.m., the Changjuang Reservoir on the western edge of the city developed what engineers call a piping failure, a hole forming inside the dam itself. Under Zhengzhou's own flood emergency plan, that alone was supposed to trigger the highest level of emergency response. Nobody pulled it.

[00:04:54]Between 1:00 p.m. and 3:00 p.m. in the steep mountain districts west of the city, flash floods were tearing through valleys [music] and villages. More than 90% of the 251 people who would die there that day were already dead, which the government did not yet know. Between 4:00 and 5:00 p.m., the national weather station inside Zhengzhou recorded just over 8 in of rainfall in single hour.

[00:05:21]The previous mainland China record had stood for 46 years, set in 1975 during a typhoon flood in the same province that killed tens of thousands.

[00:05:34]The 2021 [music] storm broke that record in a single afternoon. By the end of the day, the same station would record more than 24 in of rain in 24 hours, roughly a year's worth of rain in a single afternoon and evening. At 4:30 p.m., after the record had already been broken, after the reservoir had already failed, after most of those who would die in the western mountains were already dead, the city finally activated its highest emergency response. Metro line 5 was still running. Ridership had not been reduced. [music] Ding Xiao Peng was at work, and so were several hundred other people who, within the hour, would board the same loop train as her. At about 5:00 p.m. on the evening of July 20th, the train left Haitansi Street Station heading clockwise on the outer loop toward Shakou Road Station. The two stations sit on either side of the Wulongkou parking lot. About 3 minutes into the run, a switch failure triggered an alarm, and [music] the train stopped roughly 650 ft short of the next platform. At 5:46 p.m., without diagnosing the fault, the dispatcher released the train and allowed it to proceed. One minute later, water rose above the rail surface. Under article 32 of the urban rail transit operations management method, a train is not permitted to run when standing water on the line is above the rail. The driver stopped the train. Inside the operations control center, the chief dispatcher gave a different order. Without investigating the situation outside, he told the train to reverse. The train backed up about 100 ft before losing power. It would not move again. Its final resting position was nearly 3 ft lower in elevation than where it had stopped a minute earlier, meaning the dispatcher's order had pushed the carriages into [music] deeper water. The tunnel ran east to west into rising ground. Water flowed in from the rear of the train and rose faster at the back than at the front. Hundreds of passengers gathered in the first three carriages and the water reached chests at the front and necks at the back. The network-wide order to stop all trains was not issued until 6:04 p.m. By then, the train in which Ding Xiao Pei stood had already lost power. An evacuation through the lead carriage door began, but was halted at 6:37 as the water surged. Zhengzhou Metro Group's headquarters was not notified by its own operations subsidiary [music] until 7:48 p.m. More than an hour after passengers had been posting on social media that they were trapped inside the carriage. A young man tried to break a side window, but an older man stopped him. The water outside the carriage was higher than the water inside and breaking the glass would have flooded the carriage in seconds. By survivor accounts, that single decision is the reason most of them survived. Ding Xiao Pei recorded a short video on her phone. She posted to her followers, "If no [music] rescue comes in 20 minutes, several hundred of us will lose our lives in Zhengzhou subway." A woman identified only by her surname, Lee, sent messages to her cousins. She didn't tell her parents. By her own description, she began to arrange my affairs in case I died. Then, the carriage shifted. The pressure of the water tilted it to one side and the windows on the higher side rose above the water line. Someone realized those windows could be broken safely, not for escape, but for air. A fire extinguisher was passed forward through the crowd and the first high window cracked. Oxygen returned. By that point, passengers were already showing signs of low [music] oxygen and low blood sugar and the pregnant women, the children, and the elderly were in the worst [music] condition. After hours, rescuers reached the train and passed in a proper window-breaking tool. The evacuation began through the open front door [music] of the lead carriage. By the passengers' own decision, the order was pregnant women first, then children, then women, then men. By one survivor's account, even couples let go of each other's hands. At 10 past 3:00 in the morning of July 21st, the last living passenger from the train [music] was brought to the surface. 14 people in that carriage did not come out alive.

[00:10:05]Above [music] ground, the rain had stopped hours earlier. The first official death toll for the entire flood was set at 99. The figure of 99 held for several days, even as the visible damage across the city told a different story.

[00:10:21]The foreign press began to notice. Over the following weeks, the number began to climb. 302, then 322, then 339.

[00:10:32]Each step came after pressure from the central government. On August 20th, 2021, an investigation team sent by the State Council arrived in Zhengzhou. It was the first whole-area natural disaster investigation in the history of China. Over the months that followed, the team reviewed more than 90,000 documents, ran more than 100 site inspections, held 200 internal discussions, and interviewed more than 450 people. The investigation found that the city had been concealing deaths. The breakdown was 75 hidden at the city level, 49 at the county level, and 15 at the township level. The total was 139.

[00:11:14]The methods included four straight days of simply not uploading numbers to the national reporting system, and demanding identity verification from family members before any death could be reported up the chain. The final official death toll was 398.

[00:11:31]Nearly all of those deaths, 95.5% were inside Zhengzhou itself. The official death toll on the train Ding Shaopei was in was set at 14. The investigation classified the Metro Line 5 incident as a liability accident, a formal Chinese legal category meaning the deaths were preventable and fault could be assigned. The contractor that built the Wulongkou wall had used unauthorized draft plans instead of the approved drawings, and the redesign that lowered the depot below street level had never been submitted for approval as Chinese construction law required. Eight people connected to the design and construction of the parking lot were arrested on charges of major safety accident crimes. Among them, the parking lot's design lead, the project lead at the Beijing-based design group, and the construction company's project director.

[00:12:27]In all, 89 officials were disciplined.

[00:12:30]The city's party secretary and mayor were both demoted in rank, and the vice mayor responsible for emergency response was removed from his positions in the government and the party. Of the 19.6 billion yen that had been invested in Zhengzhou's sponge city projects, only 32% had gone to sponge [music] city work.

[00:12:51]Nearly 56% had been spent on landscaping. But why couldn't these people escape in time?

[00:12:58]Because they didn't know what was coming. And by the time they did, their train [music] had stalled in a tunnel between stations because in the final minute, when it might still have been walked out, a voice in the control room ordered it to reverse deeper into the water because the wall that should have kept the water out had been illegally redesigned to fail, and the warnings that should have shut the city down were ignored at every level over a weekend the investigators called blank. Ding Xiao Peng's video survived, so did she.

[00:13:30]The 14 who did not walk out of the carriage have never been publicly named.

[00:13:35]The kind of rain that fell on Zhengzhou is projected to arrive in northern China more often, not less, and the walls have still not all been rebuilt.