Flood Deaths in China Reveal Road Risks from Climate Change


ZHENGZHOU, China — More than 200 cars were caught in a highway tunnel in central China on Tuesday as record levels of rainfall soaked the area. The water pouring into the entrances of the tunnel filled it almost to the ceiling.

The death toll would likely have been higher that day had it not been for the semi-retired special forces commandos, who swayed and swam back and forth between colliding vehicles to rescue drivers who drowned as their cars flooded and sank. Authorities are still evacuating the tunnel, and they said at least four people were dead.

Initially, international attention transport safety risks from extreme weather conditions focus drowning in subway tunnel It filled with water during the same cloud eruption in Zhengzhou in central China’s Henan Province. But transportation safety experts said this weekend that highway tunnel flood deaths highlight the risks that climate change can pose for drivers as well.

Kara M. Kockelman, a transportation engineering professor at the University of Texas at Austin, said the deaths really show that road engineers, such as subway system designers, must deal with the heavier rainfall linked to climate change.

A highway tunnel “could really fill up like a bathtub in some of these rainstorms,” ​​he said, “and will only get worse due to climate disaster.”

In 2011, a group of Chinese experts published a white paper pointing out that the Zhengzhou tunnel, which is still being built, is located in a low-lying area where stagnant water often forms on the streets. The tunnel opened in 2012.

It was built with a pumping system designed to withstand enough rain to fall every 50 years. But authorities have since described Tuesday’s flood as an event that, in theory, happens at least once every 1,000 years.

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

Another body was found in the subway tunnel, the provincial capital city of Zhengzhou said on Saturday, bringing the official death toll from the subway flooding to 13. Overall, the state death toll from flooding rose to 58, with 5 missing.

As bright sunlight dried up the streets of Zhengzhou on Saturday, many communities in northern Henan Province continued to face high waters. “Some villages have been besieged by flooding and need to evacuate large numbers of people,” Guo Huajie, chief engineer of the Henan Fire and Rescue Corps, said at a government press conference on Saturday.

The highway tunnel debacle could easily have been much worse, as 200 to 300 cars were stranded in the rapidly rising waters.

But a man in a white shirt, who was spotted swimming confidently among sinking cars on Tuesday, pulled drivers to safety. He was identified by local media and his employer as Yang Junkui, a former People’s Liberation Army commando late Friday.

Mr. Yang, 45, told Shanghai news outlets that he had received automated cell phone alerts of heavy rain from the government and his employer in the early afternoon on Tuesday, so he started driving home from work as the driver of Caocao, a ride-hailing company. Uber.

He was passing through the tunnel when it started to fill with water and traffic stopped, and he left his own car when the water reached the axles just before the cars around him began to float. He started knocking on other drivers’ doors, telling them to get out of their vehicles and taking them to a safe place.

The three women, who apparently could not swim, were abandoned nearby on the roof of a sinking car as the two men left them and went to safety. Mr. Yang jumped back into the water and took the women out one by one. He then unsuccessfully tried to save other drivers, but backed off after hurting his leg.

“I was neither hesitant nor scared, but I got a little scared over the past two days after reaching the side,” he told Shanghai news outlet Jiemian.

Mr. Yang agreed to do an interview early Saturday afternoon, but canceled at the last moment. Caocao said he had returned to his hometown north of Zhengzhou as he was about to be partially submerged by a controlled discharge of water from a reservoir.

Similar controlled releases During the 1993 Mississippi River floods In the Midwest, to relieve pressure on dams when the water behind them rises dangerously.

Just two months ago, the Henan Province government was promoting “smart tunnel” investments in the same mile-long four-lane highway tunnel that flooded Tuesday. The sensors can be used to track and precisely position any person or vehicle and closely monitor the tunnel’s water pumps. An artificial intelligence system can be used to instantly analyze problems and suggest solutions.

Highway tunnels, including those in Zhengzhou, are built with their own pumping systems. But, like last week, extreme cloud bursts with eight inches of rain in an hour pose formidable challenges for road designers.

To work, such pumping systems must be able to move water to a place where it is not submerged. Zhengzhou is almost flat and slow to ejaculate. The entire street at the south end of the tunnel filled with water several meters deep.

Dr. Kockelman said any investigation into what went wrong in Zhengzhou should examine whether the pumps’ outlet was submerged. This can reverse the direction of the flow of water passing through the pumps, causing it to fill the tunnel.

Liu Chunge, owner of a small grocery store sitting two steps above the pavement at the south end of the tunnel, said the water in the streets was rising rapidly. Before long, he was calf-deep inside his shop.

The freezer where he was selling ice cream started floating on the water, so he poured beverage bottles over it, forcing him to lower it to the ground.

“I have never experienced such a big flood before,” said 50-year-old Ms. Liu. “In previous floods, the water had never risen above two steps.”

Zhengzhou officials have held three press conferences since the tunnel flooding, but have yet to directly explain what went wrong.

Local authorities struggled to remove water from the highway tunnel. By Friday afternoon, they were running a pair of pumps, almost the size of commercial jet engines, attached to bright red, fire truck-sized suction trucks at the south end of the tunnel. But the muddy water in the tunnel was still deep enough, and only the roof of a white car was visible inside.

Several workers maneuvered a large yellow tow truck to try to pull a mud-covered black minivan out of the tunnel’s exit. The van’s rear wheels were on a carriageway almost a yard high, and the driver’s door was open. Five mud-drenched cars and pickup trucks lay in the nearby water, including a navy blue Ford sedan with a white car on the roof.

Many Zhengzhou residents watched and filmed the teams’ work on Friday afternoon and were chased at times by several municipal police.

As for Mr. Yang, Caocao gave him a new $25,000 electric minivan Friday night.

joyful, Claire Fu and Liu Yi contributed to research.


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