Zhengzhou hit by massive floods due to heavy rainfall

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In summary, the 2021 Henan floods in China have caused a grim situation in Zhengzhou, with many people displaced and utilities out of service. The heavy rainfall, reaching 2.01 m/h, caused a metro to get trapped in a flooded tunnel and resulted in the death of 12 people. The situation is catastrophic, with flooded hospitals and doctors using manual ventilators to save lives. There are also concerns for downstream areas on the Yellow River, but experts believe the river can handle the amount of water caused by the precipitation. Comparisons have been made to the floods in Europe, with Germany receiving similar amounts of rainfall, leading to devastating consequences. There are also concerns about government accountability and potential consequences for those in positions of power
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Leo Liu
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https://en.wikipedia.org/wiki/2021_Henan_floods
The situation in Zhengzhou is still grim as the utilities are out and many people have been displaced. At around 5PM on July 20, the level of rainfall reached 2.01 m/h. The flood created by the rain rushed into a subway station from a ventilation chimney, causing a metro to get trapped in the tunnel, in which the water raised above the necks of many passengers. 12 people died in this accident.

A netizen also posted a picture featuring a flooded public hospital, with which they claimed that electrical power was unavailable, the backup batteries were drained, doctors were using manual ventilators to save lives, and the patients were dying.
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BBC news report:
https://www.bbc.com/news/world-asia-china-57861067
Collection of videos/pics depicting the situation in Zhengzhou:
https://twitter.com/search?q=zhengzhou+china&ref_src=twsrc^google|twcamp^serp|twgr^search
Compilation of videos showing the the impacts of the floods (NSFW)

I wish that people in Zhengzhou stay safe.
 
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The planet has had enough of us and I can't say I blame it.
 
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Saw some of the subway pics. Any implications for those downstream on the Yellow River?
 
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BWV said:
Saw some of the subway pics. Any implications for those downstream on the Yellow River?
No so many to my knowledge. I guess it's because the Yellow River could handle far more volume per unit time than the amount of water caused by the strong precipitation in the city of Zhengzhou. I will inform you if I have more information on this matter.
 
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Leo Liu said:
No so many to my knowledge. I guess it's because the Yellow River could handle far more volume per unit time than the amount of water caused by the strong precipitation in the city of Zhengzhou. I will inform you if I have more information on this matter.
Hope so, we have seen high levels of upstream rainfall lead to floods hundreds of miles downstream in the Mississippi river
 
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Leo Liu said:
2.01 m/h.
The rainfall in one hour was as high as 201.9 mm (7.95 in), or 0.202 m/h, which is still a heavy rainfall. Even 0.05 m/h is considered heavy. On hilly ground, the rain on the ground will flow to the lowest area, so low lying areas will fill with water, or valleys become streams or rivers.

Nevertheless, the rainfall rates are extraordinary, and of course, the flooding is catastrophic.
 
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Astronuc said:
The rainfall in one hour was as high as 201.9 mm (7.95 in), or 0.202 m/h, which is still a heavy rainfall. Even 0.05 m/h is considered heavy. On hilly ground, the rain on the ground will flow to the lowest area, so low lying areas will fill with water, or valleys become streams or rivers.

Nevertheless, the rainfall rates are extraordinary, and of course, the flooding is catastrophic.
Zhengzhou received the same amount rainfall in two hours as Belgium did over two days. I can't find any data about the precipitation in Germany so I couldn't compare.
 
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BWV said:
Hope so, we have seen high levels of upstream rainfall lead to floods hundreds of miles downstream in the Mississippi river
Meh, even if there were floods down stream due to the unanticipated increase in the amount of rainwater, I doubt the government would disclose their existence, as it now busies itself with casting as much positive mood onto the public as they can to ensure that people won't question about the misconduct of the provincial government. But I am pretty sure someone is going to get fired to shift the blame from the system to a particular person, just as the central government removed the former mayor of Wuhan after the outbreak of COVID even though he was just executing commands from the top.
 
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Floods on China’s two rivers created some of the worst natural disasters in history, with death tolls in the hundreds of thousands or millions - largely due to subsequent outbreaks of cholera and other diseases and/or malnutrition from disruption of food supplies. Found this video on some of the unique features of the Yellow River

 
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Leo Liu said:
Zhengzhou received the same amount rainfall in two hours as Belgium did over two days. I can't find any data about the precipitation in Germany so I couldn't compare.

More than 7 inches (178 mm) of rain fell on parts of the western German states Rhineland-Palatinate and North Rhine-Westphalia between Tuesday and Thursday— roughly double the normal expected rainfall for the whole of July, . . .
https://time.com/6081472/germany-flooding-climate-change/

More than 182mm (7.2ins) fell in 72 hours in some areas between 12 and 15 July, according to Deutscher Wetterdienst - the German meteorological service.

Among the worst-hit parts of Germany, the area of the city of Cologne known as Köln-Stammheim saw more than 153mm of rain on 14 July. To put that in context, it is six times higher than the average heaviest rainfall days for the area in July.
https://www.bbc.com/news/world-europe-57862894
CNN, July 22 - A week after severe flooding hit western Europe, devastating Germany, Belgium and the Netherlands, German officials said Thursday they fear the 158 people still missing there may not be found.
The death toll from the floods has risen to at least 205 across the continent, while a total of at least 176 people remain accounted for. Belgium accounts for 32 deaths and 18 missing, according to its national crisis center.
https://www.cnn.com/2021/07/22/europe/germany-belgium-europe-floods-death-climate-intl/index.htmlAbout 11 years ago, at my house, we had two successive weekends where on Friday it rained about 10-12 cm of rain, then ~35 cm during all of Saturday, then 5-10 cm on Sunday. The first time, the water trickled into the basement. The second weekend, the hydraulic pressure was so great in the ground that I jets of water shooting into the basement, so I had to set up a pump in the basement to run more or less continuously because of the flooding. We have a hill behind our house and the basement is the lowest point on the property. The street is slightly above our basement elevation, but the utility easement is fortunately lower, so that's where we pumped the water from the basement. Since, we have installed a trench system, sump and pump to remove any water entering the basement.
 
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Update: To my dismay, more tragedies in Zhengzhou were revealed. Among one of them is the 2-km long tunnel on Jing Guang Road, which was fully filled with rainwater.



Rescue mission is now underway: https://www.thepaper.cn/newsDetail_forward_13692786

It was said that there were at least several dozens of vehicles in the flooded tunnel. It only took the rain a short period of time to fill it, so it is unlikely that people deep in the tunnel had exited the tunnel before it was too late.

This is the most devastating news about the flooding in Zhengzhou so far. My heart goes out to the victims of this incident. 😢 RIP.
 
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FAQ: Zhengzhou hit by massive floods due to heavy rainfall

What caused the massive floods in Zhengzhou?

The massive floods in Zhengzhou were caused by heavy rainfall in the region. The city experienced record-breaking levels of rainfall in a short period of time, leading to flash flooding.

How severe were the floods in Zhengzhou?

The floods in Zhengzhou were extremely severe, causing widespread damage and loss of life. Over 25 inches of rain fell in just three days, leading to flooded streets, collapsed buildings, and disrupted transportation.

Was this type of flooding expected in Zhengzhou?

No, this level of flooding was not expected in Zhengzhou. While the city experiences heavy rainfall during the summer months, the amount of rain that fell in such a short period of time was unprecedented and caught many by surprise.

How did the government respond to the floods in Zhengzhou?

The government responded quickly to the floods in Zhengzhou, mobilizing resources and personnel to assist in rescue and relief efforts. The city's flood control system, including dams and reservoirs, was also utilized to help mitigate the effects of the flooding.

Are there any long-term solutions to prevent similar flooding in Zhengzhou?

There are several long-term solutions that can be implemented to help prevent similar flooding in Zhengzhou. These include improving the city's drainage system, building more green spaces and wetlands to absorb excess rainwater, and implementing stricter regulations for urban development in flood-prone areas.

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