ZHENGZHOU, China – The heaviest hour of rain on record in China crashed as a kilometer-wide waterfall in the city of Zhengzhou on July 20, killing at least 300 people, 14 of whom were drowned in a subway tunnel.
In the process, regional and national officials initially suggested that little could have been done in the face of a storm of this magnitude.
But an analysis of how authorities responded that day, based on government documents, interviews with experts and Chinese reports, shows flaws in the design of the metro system and missteps in the metro system. his operations that day almost certainly contributed to the deaths in the tunnel.
Zhengzhou’s struggles hold lessons for other urban centers in the age of climate change, including New York City, which closed its subway on September 1 in a downpour of less than half.
The flood showed the challenge that global warming poses to China’s go-go development model of the past four decades. He highlighted questions about the ability of Chinese cities, including its subways, to cope with more frequent extreme weather conditions. The Zhengzhou metro didn’t start to reopen until Sunday.
“We humans must learn to dance with wolves and survive in extreme weather and climate conditions,” said Kong Feng, associate professor of disaster and emergency management at the China Agricultural University in Beijing, “because we currently have no better way to stop it. “
The Chinese government now appears to recognize the missteps of local authorities, as well as the possibility that severe weather events are becoming more common. During a visit nearly a month after the floods, Li Keqiang, Chinese Premier, warned that the country must remedy any lack of preparedness “to warn future generations.” A government investigation team referred unspecified “acts of dereliction of duty” to law enforcement, according to an official statement.
The subject has become politically sensitive. Posts critical of the government’s actions have been removed from social media platforms. A Communist Party organization encouraged harassment of foreign journalists covering the disaster.
Yet the images and stories resonated across China before fading away. Deep in the subway tunnels, water raged outside the windows of a train like turbulent brown rapids. Commuters struggled for air as the water rose.
“I felt like I was just there waiting for my death, even though I didn’t know how, whether from suffocation or drowning,” said Zheng Yongle, a passenger stuck on the Line 5 train. from Zhengzhou.
The 14 deaths on Line 5 were only part of the disaster, which temporarily displaced 1.4 million people, but they deeply affected the public.
On the night of July 19, the Zhengzhou Weather Service issued the first in a series of emergency alerts that continued into the next day. According to government regulations in Henan Province, which includes Zhengzhou, the alerts should have triggered the shutdown of all but essential businesses. For reasons that remain unclear, the city has not issued such an order.
The rain peaked with the record gust of July 20. From 4 p.m. to 5 p.m., 7.95 inches of rain fell, double what authorities had expected over the next three hours. The deluge has been compared to an hourly peak of 3.15 inches in New York City on September 1 and similar peak precipitation during the deadly floods in Tennessee on August 21.
Christopher Burt, weather historian for Weather Underground, a forecasting affiliate of IBM, said it was the heaviest hour of precipitation measured reliably in the center of a major city in the world.
“The showers in Zhengzhou and Manhattan show that climate change means that existing calculations of the frequency of torrential rains may no longer be valid,” he said.
The Zhengzhou Metro subway system, including its pumps, drainage ditches, and pipes, was designed to meet central government drainage standards, but only for the type of storm that the previous assumptions were made would have. must have had a one in 50 chance of occurring in any given year.
In contrast, Zhengzhou meteorologists estimate that a downpour like the one in July had less than a 1 in 1,000 chance of happening in a year, although China’s national weather agency warned the country only has data. reliable dating from the early 1950s.
City officials had conducted emergency drills for heavy flooding, but not for a cataclysmic downpour, said Mr. Kong of the China Agricultural University.
“There are hidden vulnerabilities in the city, which were never discovered until this disaster struck,” he said.
One vulnerable point in the metro system, officials said, was a retaining wall built in an area the city identified more than a decade ago as prone to flooding. The wall was next to a maintenance yard and next to the base of a slope. A six-lane avenue ran down the slope of a row of 30-story apartment towers.
As the waterspout raged, the water poured down the slope. The wall collapsed. Water poured into the tunnels used to bring trains to the surface for cleaning and repair, filling Line 5, one of the newest and busiest in the system.
The retaining wall collapsed around 6 p.m., according to Zhengzhou Metro, 10 minutes before authorities shut down the metro. Social media accounts show that there had been flooding in the system before that date.
“If the metro could have suspended services in advance, casualties could have been avoided,” Kong said.
By this time, water had already started to flood a train on line 5, which circles the city center. Mr. Zheng and more than 500 other passengers were trapped.
Authorities in Zhengzhou have yet to reveal why the trains continue to run. The next day, China’s transport ministry said subway drivers could act immediately in response to safety concerns and check with their dispatchers later.
During the flood, the subway seemed to be a lifeline for those still trying to get around the city.
Wang Yunlong told Chinese news agencies that he and a colleague on a business trip from Shanghai decided to take the subway because they couldn’t hail a taxi from their hotel.
Although the Zhengzhou Metro started to close some entrances, they were able to board a Line 5 train at Huanghe Road Station. He only made two stops before encountering difficulties at the Haitian temple station, where he stopped for about 20 minutes.
At 5:50 p.m. the train started moving again, heading towards Shakou Road through a tunnel that sinks into the deepest stretch of Line 5. The conductor stopped between the two stations as the tunnel began. to fill with water. He tried to reverse the train. It was too late.
What happened next unfolded in terrifying detail in photographs and videos posted on China’s social media platforms.
Some passengers were able to exit the train from the front and make their way to Shakou Road station through dangerous water breaking through the tunnel. Mr. Wang and Zou Deqiang were among those who tried, but Mr. Zou lost his grip and was swept away by the torrent.
Witnesses told of a slow and confused effort to clear the tunnels, as passengers searched for oxygen near the ceilings of train cars as the murky water rose. Rescuers were able to join the train when the waters began to recede around 9 p.m., people present said.
Deaths caused demand that those responsible be held to account.
The widow of Sha Tao, another deceased passenger, posted a message on Weibo accusing the subway of continuing to operate. In a telephone interview the day after the floods, she described her desperate search for him. She complained that authorities were slow to search for him after the metro flooded.
His body and that of Mr. Zou were found almost a week later.
“The responsibility of the Zhengzhou metro,” she wrote, “is heavy and cannot be shirked. “
Keith bradsher reported in Zhengzhou, China, and Steven lee myers from Seoul and San Francisco. Li you, Liu Yi, Claire Fu and Amy Chang Dog contributed research.