As torrential rain hit one of China’s most populous regions on Tuesday, passengers on the No. 5 subway line in the central city of Zhengzhou found themselves trapped as flood water poured into underground tunnels and filled up the train.
In a matter of hours, muddy water reached everyone’s necks in the crowded cars. Some passengers started crying in panic. Just breathing was a struggle for some as dozens shared a shrinking pocket of air beneath the ceiling, according to several survivors’ accounts.
“I texted my mother, ‘Mom, I don’t think I can make it, I’m scared,’” a survivor wrote in a post that was shared by state media on the microblogging site Weibo. “I was on the brink of breaking down.”
At least 25 people were killed by the flood in Zhengzhou, including 12 who died in the flooded metro system, the government said on Wednesday. The horrifying images and Zhengzhou residents’ desperate calls for help online have shocked the country, raising questions about the city’s preparedness for a future where such extreme weather events will become more frequent.
The two feet of rain that soaked Zhengzhou, the capital city of Henan province, from Saturday to Tuesday was almost as much as the rainfall the city typically gets in an entire year. The local meteorological authority said the downpour was seen only “once in a thousand years.”
The rain was disastrous to many of the millions of residents in Henan. A hospital with nearly 10,000 in-patients had a power outage on Tuesday, forcing medical workers to use hand pumps to give oxygen to patients.
Overground trains were forced to stop in their tracks between stations. By Wednesday, several trains carrying thousands of passengers were stranded in Henan province, some for more than 40 hours, according to news outlet Caixin. Food and water were running out, but passengers had no other places to go.
On Weibo, SOS messages have been popping up from people in the flooded areas: someone was trapped on top of a truck in the middle of the flood. Some were stranded inside garages, family cars or hotel rooms. Many others said they could not reach elderly parents in the villages, where many houses had been destroyed by the flood. A full accounting of the widespread damage could yet reveal more casualties.
Some say the wave of desperate cries for help reminds them of the beginning of the COVID-19 pandemic in early 2020, when residents in Wuhan took to social media to plead for protection gear and hospital beds.
Although such extreme weather is rare, Chinese cities are regularly swamped by massive floods that result in casualties and heavy financial losses. During the flood seasons, urban-dwellers have joked that they could enjoy “sea views” from inland cities.
Researchers say the country’s rapid urbanization has led to climate effects that increase precipitation. For example, the elevated temperatures of cities could create an “urban heat island effect” that causes heavier rainfall. Flooding is further exacerbated by the inadequate drainage systems and disconnected natural water bodies that could otherwise absorb heavy rain.
In 2013, the Chinese government introduced a “sponge city” initiative to build eco-friendly infrastructure, such as green spaces, artificial wetlands, and rain gardens, that could soak up excessive rainwater. As one of the pilot cities, Zhengzhou has invested more than 53 billion Chinese yuan ($8 billion) so that by 2030, its urban area will be able to withstand once-in-50-years rainstorms.
Faith Chan, an associate professor with the School of Geographical Science at the University of Nottingham Ningbo China, said that compared with coastal cities, inland metropolitan areas like Zhengzhou have fewer waterways to drain the rainwater.
But Chan said while many Chinese cities do need to upgrade their drainage systems, it is not realistic to invest in infrastructure that could withstand extreme weather that occurs once in hundreds of years.
“For this kind of rain, it would be difficult for any city,” Chan said. “What [authorities] can do is to improve the responsive measures, which are education, warning, communication and emergency services.”
A security officer at the Zhengzhou metro told Chinese newspaper Southern Weekly that he did not foresee the flood entering subway stations. The metro operation was suspended at 6 p.m. on Tuesday, but with a power blackout, the water could not be immediately pumped out of the stations.
Before they were rescued, passengers inside flooded trains wondered if their subway ride would be their last.
A survivor told the China Youth Daily that at around 9 p.m., most of the trains were completely flooded, and passengers all moved to the three cars on the front. Passengers, including pregnant women, children, and elderly people, were exhausted and sick. Some started trembling and retching due to low blood-oxygen levels, or hypoxemia, and low blood-sugar levels.
A few people managed to break the windows with fire extinguishers and let fresh air in, the survivor said. Rescuers later opened up an exit at the front, and passengers eventually walked to a nearby subway station.
The woman who posted her experience on Weibo said firefighters arrived later to break the windows and helped passengers get out of the train. The government said at 4 a.m. on Wednesday that more than 500 people had been rescued from the subway system since Tuesday evening.
“This is the first time in my life I was so close to death,” she wrote. “Now that I’m fortunate enough to survive, I’ll do my best to enjoy life in the future, and treasure the people and things around me.”
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