Simone Gao: Welcome to Zooming In China, I am Simone Gao. First of all, I will show you a video collections from a channel called the China Tragedy Archive. These videos are uploaded by citizens from Zhengzhou City where the big flood happened. It shows the situation of the Jingguang Tunnel in Zhengzhou City after the flood subsided. You can see that there are many cars floating on the water, piled together. There are many dead bodies in the car.
Witness: These are families in the cars, several hundred of the cars, local people estimate casualties may reach 3digit.
Simone Gao: Many Zhengzhou citizens came to this place to look for their missing relatives, but the area has been surrounded by armed police and the people are not allowed to enter. There was a conflict between the people and the armed police.
Witness: Near Jingguang Tunnel, police blocked the road and people can not get close.
Witness: Something must have happened, we all know in our hearts, there are things they don’t want us to know. Let’s pray, I hope there are not too many casualties.
Witness: Things are worse than we thought. Cars came out of water. They are everywhere.
Witness: Cars are everywhere.
Simone Gao: Next is my interview with Chinese water conservancy expert Wang Weiluo. It is precisely about why Zhengzhou spent more than 7 billion dollars to build a flood control system, but the result has been so poor.
Mr. Wang, thank you very much for accepting my interview. First of all, I would like to ask a specific question, that is, this time in Henan, the flood submerged the subway in Zhengzhou. The flood came in quite fiercely. I think, when people enter the subway, that is a very short time. It may take ten or twenty minutes to spend in the subway, so they didn’t feel the danger upon entering the subway. Then the flood came in immediately, so what do you think of this? What happened? Why did the flood come down suddenly?
Wang Weiluo: There is a report that one of the retaining walls at the exit collapsed. It was suddenly destroyed by the flood, and then the flood came along the underground pipeline of the subway here.
In fact, according to the safety device design and operation requirement, the subway should have its safety device. If water gets into the subway, there will be an automatic response in the subway. It must stop running and must be rescued. And in this subway station, because it is underground, it also has the standard for flood control. In other words, it has the standard of being able to defend against floods that occur once in many years.
Then, according to the overall plan of Zhengzhou City, the master plan that must be completed by 2020, it must be able to release the once-in-five-years flood on the subway line, underground traffic passages, and underground squares. This standard is still quite high, the subway line must also have this pumping facility to be able to drain it.
So in the end, the subway company must be able to rescue and must take rescue measures. They must not let this subway car soak for a few hours and not try to rescue it. This is just a joke! I can’t understand. This is incomprehensible. For example, there is a subway in the U.S. The middle of it is blocked by water. Then you have to go in and rescue people from both ends right away, right?
There is also the easiest thing. All subways in Germany have a percussion hammer next to the window. The percussion hammer means that when this crisis is reached, the window must be broken, and then you can climb out, even if the water outside is already very deep. At this time, the car roof is much safer than inside. It must have a percussion hammer. You can’t let them use this firefighting, fire extinguisher to hit this toughened glass. The percussion hammer is necessary equipment. These preventive measures are poorly done in China.
Simone Gao: Now there is a speculation: Zhengzhou has a Changzhuang Reservoir. The Changzhuang Reservoir exceeded the warning level in the past two days. So, they released the flood from this Changzhuang Reservoir later. But when the flood was discharged, we don’t know if they informed the people living downstream or not. So, there is a speculation that the reason Zhengzhou has suddenly flooded so much, including in the subway, is because they discharged the flood from the Changzhuang Reservoir.
Wang Weiluo: This is directly related. Why do you say that? Where is Changzhuang Reservoir? Everyone understands that the warning water level is 128 meters. Changzhuang Reservoir’s had reached 130 meters. In fact, the water level of its flood control check is 134 meters, and still has the ability to store some more water, but why didn’t they do that?
Because the reservoir had already experienced piping earlier
What is piping? For a dam, the side that can block the water is called the water retaining surface, and the back side is called the opposite side of water surface. Piping is water that goes through the dam and comes out from the back side of the dam. When the piping occured, it was still a little bit of water. However, as the water flows and becomes larger and larger, a water pipe will be formed that way, bigger and bigger. If no measures are taken, a big hole will appear and the dam will break.
So, for dealing with dam piping, the current rescue technology is pretty good. They put a layer of flood-control cloth, created in the Netherlands, immediately on the water diversion surface. This way, the flow will be slowed down so that the hole behind it will not expand. As long as this measure is taken, accidents can be prevented. So, from that point, the Changzhuang Reservoir should have started to discharge water.
A very big problem is that the river under the Changzhuang Reservoir is called Jialu River which is named after a water conservancy official from the Yuan Dynasty. He was the water conservancy official who governed the Yellow River. He wrote a book called Hequzhi. In it, there is a very important sentence. He wrote: “it is not that the river violates you, it is you who violate the river.” He said the root cause of flood is not the river violates people, but otherwise. We know that the Jialu Rive is the main river that passes through Zhengzhou City. People in Zhengzhou City call her the Mother River.
A reporter said that when the Changzhuang Reservoir began to discharge floods, it was a flood discharge of three cubic meters per second. That’s a joke. That is not called flood discharge, that is called peeing. Three cubic meters per second. That is a very small flow. Then he said later that it was forty-three cubic meters per second, which was also a joke. And the report also said that the water level of the reservoir started to drop. This is also a joke, because this small flow is not enough to make the water level of the reservoir drop. Then there is a report that the flow of this flood discharge has reached 525 cubic meters per second. This figure is more acceptable and more reliable. Maybe the discharge volume was even larger than that. So, the reports said that the Jialuhe River measured 600 cubic meters per second at that time. What is the flow that Jialuhe river can pass through now? It is 400 cubic meters per second, so the lower limit of the Changzhuang Reservoir ‘s discharge volume exceeds the flow that the Jialu River can accept.
Why is the capacity of the Jialu River so small? Because Zhengzhou City dressed up its mother river beautifully when it was building the city. Let her walking a long way from the southwest of Zhengzhou City, then to the northwest, round the mountain ring, and then reach it’s east, walking from the east to the southeast. The river spanned a full half circle here. The Jialu River spans a half circle around the city center of Zhengzhou. There are also several tributaries of the Jialu River. Then, they let the tributaries go through the city center of Zhengzhou. Meeting with the Jialu River, a water town with dense rivers is formed. So, the cities have three lakes, wide and narrow rivers, and wetlands as well. So, the city said the entire water system is very beautifully arranged.
Therefore, the city said that its river is a very beautiful river, but they forgot that the main function of a river is the river. It is to discharge floods. When the flood comes, the river is to discharge floods. it doesn’t play around with you. It is not a decoration.
Why does Zhengzhou want to arrange its water system like this? Zhengzhou City has built 21 new developments on both sides around the Jialu River and the South-to-North Water Diversion Project. This is the residential area. This is Zhengzhou City. This is a real estate hotspot. The plan is to sell 300,000 houses here every year for 900,000 people to live in, for a total of 2.7 million people to live in this area in three years, all around the beautiful Mother River we just mentioned. By leasing these lands to developers, the Zhengzhou government can make a lot of money. But they forgot the river’s limited passing ability. The widest place in the river may be 350 meters. The narrowest place is only 90 meters. it could not pass the 600 cubic meters of flood discharge that came down from above, so it overflowed the street in Zhengzhou City. So, the floods in streets in Zhengzhou City are not mainly due to the rain coming up, because the surface of the water that came up when it rained was not so turbulent. It shouldn’t flow so much, but it rose slowly. Only with the flood discharge water from the mountain and from the Changzhuang Reservoir, it can have such a flowing speed. After it overflows its river course, it runs around in the city and, at the same time, it enters the underground track of the high-speed rail.
Simone Gao: I have two questions. First of all, you just said that the subway in Zhengzhou, in fact the entire city of Zhengzhou, was submerged by floods and this is closely related to the flood discharge of Changzhuang, so before the flood discharge of Changzhuang, if the government informs the people immediately…
Wang Weiluo: They did not notify the people. They notified late. They said that it started at 10 o’clock in the morning on the 20th. They only started to discharge the flood at 10 o’clock in the morning on the 20th. But we saw a lot of things. First, they said that the flood discharge started at 10:30 in the morning on the 20th, but the news was sent out on the 21st. In other words, except that he had already started the flood discharge, he only told you that after the discharge. Before the discharge, they did not make an announcement.
Simone Gao: Why didn’t they make an announcement? Why did they catch everyone off guard?
Wang Weiluo: Because the Changzhuang Reservoir is the second water source of Zhengzhou. It mainly supplies water for the Zhengzhou Water factory. If it releases the water for safety reasons, if the rain stopped, they would suffer economic loss. What should they do? So, for the operator, they are always there to guess whether the rain is going to come. If you were the boss, what would you think? One side is the income and wages of your employees, the other side is people living downstream that have nothing to do with you or are not directly related to you. Are their houses flooded? Is that because of our discharge of flood? They rarely think this way. They must first consider their economic benefits.
Simone Gao: In other words, after they release the water, the water plant will no longer have water, they will not be able to sell the water, and they will have no income. They just keep weighing the trade-offs until the end.
Wang Weiluo: Not exactly. There is one way they can make money. If the reservoir receives an order from the Flood Control Headquarters to let the flood discharge, the money will be paid by the National Headquarters for flood prevention and disaster relief. So, as long as they don’t make a decision to discharge the water by themselves, in that case, they will release the water for nothing. Otherwise, they will get compensated by the government. So, when you talk about this mechanism, it releases water for the purpose of flood prevention. It is compensated by the state with relief funds for flood prevention. If you automatically release water, you get nothing. In China, the water plants and reservoirs belong to the state; the workers are only paid a basic salary. Most of the bonus income and benefit income of those workers depends on the water plant, this reservoir, to sell water. This is how it works after the economic reform, the introduction of the so-called capitalist management combined with socialism. So, you get the shortcomings of socialism and the shortcomings of capitalism to form a very complete and worst system.
Simone Gao: In other words, the reservoir does not have any intention to release water by itself.
Wang Weiluo: They do not have intentions.
Simone Gao:Right, they waited and waited until the country gave you the final order to release the flood.
Wang Weiluo: They wait ‘til the last minute, right before the dam is going to collapse, then the leader tells them to discharge the water.
Simone Gao: And it was too late at that time, and the notice was too late.
Wang Weiluo: As I just said, the dam has already experienced piping. The next step in piping is the dam collapsing. If they do not take measures, the dam will break.
Simone Gao: So, what is happening actually may not only happen in Zhengzhou, but similar incidents may happen all over the country?
Wang Weiluo: This happened to several reservoirs here. In fact, a reservoir in Luoyang is even more critical than this. Part of the dam has already collapsed, so they used engineer soldiers to fix it. They exploded a spillway right next to the dam so the water could be discharged from there. This was an uncontrolled discharge.
There is also the flood discharge in Inner Mongolia the day before. It is a self-flowing flood discharge, which does not have a flood discharge channel. After the water rises above the dam, it flows over. There are various ways of discharging floods, if a reservoir is designed to meet the standard, its flood discharge is designed according to the principle of the largest flood that it has suffered in history. That is to say, if it really wants to discharge the flood, they will discharge the maximum amount as happened in history.
Because when they designed it, only such a discharge capability could ensure that the water level would not rise again. So, what you can imagine is that the reservoir is already filled with water. And you are experiencing the maximum rainfall at the same time, so only if you can discharge the maximum amount of water, you can make sure the water level in the reservoir can drop. So, their flood discharge is designed according to the largest historical flood volume. Now China has made a breakthrough, Baihetan, Nuomidu’s discharge capability has exceeded the maximum flood volume in their history.
Simone Gao: With such a large amount of flood discharge, once they discharge the flood, it will have a very significant impact on the downstream?
Wang Weiluo: It depends on whether the river downstream can withstand such a large amount of flood discharge. It happens that Zhengzhou is the so-called ecological water system city. They totally forgot about this function of rivers. So, the maximum passing ability of the Jialu River, which I saw somewhere in passing, is only 400 cubic meters per second. In this case, you will get more than 500 cubic meters from the top, and add a little from the bottom to more than 600, since however long the river runs, that’s how much water it collects. Plus, the drainage in the city is carried by the river as well, so it collects the water in the city as well. In the end, it exceeds the capacity of the river. At that point, the river returns all the water back to the city, and the city is flooded. That’s why this city has such a large current and such a rush.