Flood deaths in China show road hazards from climate change

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ZHENGZHOU, China – More than 200 cars were stuck in a highway tunnel Tuesday in central China when the area was flooded by record rain. Torrents of water flowed down the entrances to the tunnel, almost filling it to the ceiling.

The death toll on that day would probably have been higher had it not been for the semi-retarded special forces commandos who swam back and forth between swaying and crashing vehicles to rescue the drowning drivers while their cars filled with water and sank. Authorities are still draining the tunnel and said at least four people have died.

Initially, international attention on the transportation safety hazards caused by severe weather focused on the sinking of a water-filled subway tunnel during the same cloudburst explosion in Zhengzhou, central China’s Henan Province. Transportation safety experts said this weekend that deaths from highway and tunnel flooding highlight the risks climate change can pose to motorists.

The deaths show that road engineers, such as designers of subway systems, will need to deal with the extreme precipitation associated with climate change, Kara M. Kukelman, professor of transportation engineering at the University of Texas at Austin, said.

The highway tunnel “could fill like a bathtub in some of these rainstorms, and it’s only going to be made worse by the climate catastrophe,” she said.

In 2011, a group of Chinese experts published a technical paper stating that the Zhengzhou Tunnel, which was still under construction, was in a low-lying area where pools of stagnant water frequently form in the streets. The tunnel was opened in 2012.

It was built with a pumping system designed to handle the largest amount of rain that would fall once every 50 years. But authorities described Tuesday’s flood as, in theory, an event that has occurred at least once in 1,000 years.

The technical paper warned that “if water accumulates in the tunnel, it will seriously threaten the safe operation of the tunnel.”

Another body has been found in the subway tunnel, the provincial capital of Zhengzhou, the provincial capital, said Saturday, bringing the official death toll from the subway flood to 13. In all, the death toll in the province from the floods has risen to 58, and it has been registered Five people are reported missing.

As bright sunshine on Saturday dried the streets of Zhengzhou, many communities in northern Henan Province continued to face rising waters. “Some villages are trapped by floods and need to evacuate a large number of people,” Guo Huaji, chief engineer of Henan Rescue and Fire Corps, said at a government press conference on Saturday.

The highway and tunnel disaster could have been much worse, with 200-300 cars stranded by fast rising waters.

But a man in a white T-shirt who was photographed by onlookers swimming confidently among sunken cars on Tuesday pulled motorists to safety. Local media and his employer reported him as Yang Junkui, a former commando commander in the Chinese People’s Liberation Army, late Friday.

Mr. Yang, 45, told news organizations in Shanghai that he received automated mobile phone warnings of heavy rain from the government and his employer early Tuesday afternoon, so he started coming home from work as a driver for Caocao, a company To transport passengers like Uber.

severe weather

updated

July 23, 2021, 11:14am ET

He was driving through the tunnel when it started to fill with water and traffic came to a standstill, and left his car when the water reached the axles, before the cars around him began to float. He started knocking on other drivers’ doors, telling them to get out of their cars and driving them to safety.

Three women, apparently not knowing how to swim, were abandoned near the roof of a sank car, as two men abandoned them and moved to safety. Mister Yang again jumped into the water and took out the women, one by one. Then, unsuccessfully, he tried to save the other motorists, but backed out after injuring his leg.

“I didn’t hesitate, I wasn’t afraid, but after getting to the side, I’ve been feeling a little scared for the past two days,” he told Shanghai’s Jiemian News.

Mr. Yang agreed to be interviewed early on Saturday afternoon, but was canceled at the last minute. Caokao said he quickly returned to his home village north of Zhengzhou because it was about to be partially flooded due to water leaking from the reservoir.

Similar controlled emissions were used in 1993 during the Mississippi River floods in the Midwest to relieve pressure on levees when the water behind them became dangerously high.

Just two months ago, the Henan provincial government was touting its “smart tunnel” investment in the same mile-long, four-lane highway tunnel that flooded on Tuesday. Sensors can be used to accurately track and locate any person or vehicle, and closely monitor the water pumps in the tunnel. An artificial intelligence system can be used to instantly analyze problems and suggest solutions.

Highway tunnels, including Zhengzhou tunnels, were built with their own pumping systems. But intense cloud eruptions like the one last week, during which eight inches of rain fell in one hour, pose enormous challenges for road designers.

To work, such pumping systems must be able to move water to a place that is not under the water itself. Zhengzhou is almost flat and slow draining. The entire street at the south end of the tunnel was filled with water several feet deep.

Dr Kockelman said any investigation into what went wrong in Zhengzhou would need to examine whether the pumps’ exit point had been flooded. This may cause the water flow through the pumps to be reversed and to fill the tunnel.

Liu Chong, the owner of a small grocery store located two stairs above the sidewalk by the south end of the tunnel, said the water in the streets rose rapidly. Soon she was inside her store.

The freezer from which she sells ice cream started to float, so I carried drink bottles on it to force it down to the floor.

Ms. Liu, 50, said: “I’ve never experienced such a big flood before. In previous floods, the water never rose above two degrees.”

Zhengzhou officials have held three press conferences since the tunnel floods, but they did not directly explain what went wrong.

Local authorities struggled to remove water from the highway tunnel. On Friday afternoon, they were operating a pair of pumps roughly the size of commercial jet engines attached to bright red suction trucks the size of a fire engine at the south end of the tunnel. But the muddy water was still so deep in the tunnel that only the roof of the white car inside was visible.

Several workers maneuvered a large yellow tow truck to try to pull a black pickup truck covered in mud from the tunnel exit. The rear-wheeled pickup truck was on an average highway about two yards away, the driver’s door hanging open. Five other cars and wagons drenched in mud were placed in the nearby waters, including a dark blue Ford with a white car on its roof.

Many Zhengzhou residents watched and filmed the work of the crews on Friday afternoon, and were occasionally pushed out by a few municipal police officers.

As for Mr. Yang, Kaokao gave him a new $25,000 electric minibus on Friday night.

Li Yu, Claire Fu and Liu Yi contributed to the research.

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