Massive flooding hits Zhengzhou after more than 200 mm (7.8 inches) of rain in just 1 hour, China

Extremely heavy rains hit the capital of China's Henan Province – Zhengzhou (population 10.3 million) on Tuesday, July 20, 2021, causing massive floods. This was the third and the strongest day of heavy rainfall in the province.

Zhengzhou received average precipitation of 457.5 mm (18 inches) within 24 hours to 17:00 LT on July 20, making it the highest daily rainfall since the weather records in the city began. 

The city has also reported record-high hourly precipitation of 201.9 mm (7.9 inches) between 16:00 and 17:00 LT (08:00 – 09:00 UTC).

The accumulated rainfall reached 449 mm (17.6 inches) on average from 18:00 LT on Sunday, July 18 to 00:00 LT on Tuesday, July 20. 

From Saturday, July 17 to Tuesday, July 20, the capital city recorded 617.1 mm (24.2 inches) of rain, nearly its annual average of 640.8 mm (25.5 inches). This is a level seen only 'once in a thousand years,' according to local meteorologists.

Zhengzhou's average monthly rainfall for July is 193 mm (7.6 inches). July is also its wettest month, followed by August with 147 mm (5.8 inches) and September with 87 mm (3.4 inches).

Severe waterlogging has led to the virtual paralysis of the city's road traffic, Xinhua reports. 

260 flights have been canceled, over 80 bus lines suspended and more than 100 temporarily detoured. The subway service has also been temporarily suspended and some trains delayed.

At least 160 000 people have been evacuated and an unknown number rescued from raging floodwaters. 

Water and electricity supply has been disrupted in parts of the city.

The city's Guojiazui reservoir had been breached but there was no dam failure yet.

The First Affiliated Hospital of Zhengzhou University – the city's largest with over 7 000 beds – has lost all power. Even backup supplies were down as the hospital raced to find transport to relocate about 600 critically ill patients, Reuters reports.

"Nearly all the hotels in the city have cut the prices to shelter the citizens who can't go home," Global Times' reporter Rita Bai said.

"The municipal library and science museums opened their doors to take in trapped people and provide them with hot water and flood."

At least 25 people have been killed and 7 others remain missing after more than 500 people got trapped in the Zhengzhou subway flood, provincial authorities said around 12:00 UTC on Wednesday, July 21.

"City authorities had halted bus services… that's why many people took the subway, and the tragedy happened," a Zhengzhou resident told Reuters.

Other parts of the province were also badly affected, with dozen other cities flooded.

At least 4 people were killed in Gongyi, a city located by the banks of the Yellow River, like Zhengzhou. Local media reported widespread collapse of homes and structures due to heavy rains.

At least 31 large and medium-sized reservoirs have seen water levels rise above the alert level after torrential rains battered most parts of the province on Monday and Tuesday, July 19 and 20.

In Inner Mongolia Autonomous Region, floods affected more than 16 000 people, as two dams collapsed on July 18 after two days of heavy rainfall — the highest since record-keeping began 60 years ago.

Featured image credit: Weibo