Wisdom of Zhihu: Beijing's Floods and How The City's Drainage Has Changed

Zhihu has long been a rich source of information about Chinese news, culture, and topics of interest. Now, we're bringing a slice of the site to English-speaking readers in our column, Wisdom of Zhihu.

Beijing has been dealing with floods for thousands of years, ever since irrigation and agricultural landsape changes left the city vulnerable to water buildup during the rainy months of summer. In a typical year, the capital sees about 70 percent of its annual rainfall in the summer, and July is the most severe.

This year, we’re already seeing higher than average numbers, with June seeing about 50 percent more rain than an average year. Now, July flooding has arrived. Beijing doesn’t have it nearly as bad as some other corners of the country (or for that matter, the world), nor is this the worst that the city has had it in recent history – a massive flood in 2012 took several dozen lives and came to be known as the 7-21 floods (referring to the date Jul 21). Nonetheless, floods today have been severe enough to affect transit as a western subway station flooded and dozens of trains were cancelled from Beijing West Railway Station.

Whenever these floods hit, netizens take to Zhihu to ask: Is Beijing prepared? In this first installment of our new column, Wisdom of Zhihu, we’re taking a look at Beijing’s infrastructural preparedness.

Question: Is Beijing’s drainage good? If so, why were there so many casualties in the 7-21 flood?

Answers:

This first answer comes from Zhihu user Hat600.

Of course, the drainage is not good. This is common knowledge.

But following the heavy rains of 2011, there actually were emergency measures put in place by the time the 7-21 floods came. If you want to look at a failure of the drainage system, look to the floods of Jun 23, 2011, when drainage failed and caused troublesome flooding with just 72mm of rain in the urban area.

But the 7-21 floods were a result of the worst rainfall in 62 years with 215mm of rainfall in the urban area. There were six deaths within the Fifth Ring Road, but the majority were in Fangshan and Fengtai and were caused by flash floods. This was not an issue of urban drainage.

This second answer comes from Zhihu user李心雨

Beijing’s Forbidden City and Qingdao’s German-made sewers are known as the “two miracles” of China’s drainage systems and can handle huge amounts of water. The water is discharged into a huge caverns, but these only attract waters at the forbidden city and Qingdao.

As the other commenter mentioned, the majority of 7-21 deaths were the result of flash floods. I remember there was death within the city proper at Guangqumen which was a guy who didn’t listen to warnings and drove into the stagnant waters under an overpass. As a result, he couldn’t open the doors in the water. This is essentially like driving into a lake.

As for the drainage system in Beijing, of course it’s not great. When it was designed, the planners had insufficient meteorological data and set the standards too low. Now it’s difficult to upgrade it even if we want to. Many drainage systems in China rely on the same outdated system... It’s all very frustrating for those of us who study the water supply and drainage.

Question: What is wrong with the drainage systems in Chinese cities and how can it be improved?

Answer:

This answer comes from Zhihu user猫老板锐视角

China’s drainage systems have been lagging for a while. This is due to a number of reasons:

1. More than half a century ago, China was largely an agricultural society with few modern cities. Whether you lived in villages on the plains or in the mountains, there was little demand for drainage, so the issue never attracted much attention.
2. The drainage pipelines in Chinese cities are too narrow. At the time of their construction, Soviet design concepts were adopted, which paid more attention to savings and resulted in relatively low overall flow capability.
3. The main cause, however, is the rapid development of Chinese cities. Some new urban areas will be planned and constructed in accordance with the latest standards, and there will fewer issues with flooding. But for older cities, it’s not an easy task to renovate the old underground drainage pipes Most foreing countries followed the constructionprocedure of “underground first, then above ground.” But Chinese cities weren’t able to due this under the historical circumstances.

Will these issues ever be addressed? Definitely yes – but first there are many other issues that China must spend its resources on to improve standard of living.

Question: How has Beijing’s drainage and flood response improved since 7-21?

This answer comes from Zhihu user 奥古斯都. The question and answer were posted in 2016 but is included here as it still serves to illustrate changes made following the 7-21 floods.

I am an employee of the Beijing Drainage Group. It is difficult for me to understand the curious mentality that everyone shows when they see the city where they live is flooded! This heavy rainfall has far exceeded the 7-21 extraordinarily heavy rain, and yet this year [2016], although there are still 13 roads flooded, it is known that the subway in the city is operating normally. So please stop with the jokes!

Urban rainwater and sewage treatment is a systematic project. In addition to the construction of a new pipe network that everyone has been paying attention to recently, what’s actually more important is that the rainwater collected by the pipe network will be delivered to dozens of sewage treatment plants. In Beijing, a severely water-scarce northern city, we have to continuously improve our urban rainwater and sewage storage capacity and recycled water utilization levels.

Furthermore, the construction of these underground reservoirs played a huge role in preventing flooding. During the 7-21 floods, 200 roads flooded. This year, that number dropped to just 13, and there were no casualties.

There is still some gap between our various efforts and the expectations of the people. Therefore, we still have a long way to go in the future, but we hope more Our work can be understood and recognized by the citizens, not the subjects of endless ridicule!

Question: Would you order waimai in Beijing during extreme weather?

Answers:

This answer comes from Zhihu user 张文骞

When I opened the Zhihu app on my break, I didn’t expect so many people to be paying attention to the plight of waimai delivery persons.

As someone who wears yellow clothes and delivers food every day, I’d like to share my thoughts.

Yesterday, I was so tired, I came home and collapsed onto my bed. I couldn’t move. Finally, I managed to get up and take a shower.

The rain a few days ago was really heavy. During the busy hours, my nose and eyes were full of water and I could barely move my scooter for fear of getting in an accident. In this terrible weather, it’s not easy to deliver waimai, but when it rains, the demand for delivery is even higher. But we delivery riders have to make money, and we know that the platform will make us work through the rain without any special bonuses.

Moreover, Meituan has always been exempt from responsibility during the heavy rain. Even if you are late due to the weather, you are the one who will be punished. At least there’s no need to worry about user complaints.

But to be honest, it’s not easy for anyone on rainy days – traffic guards still have to stand outside too. Plus, more money is more money. I have nothing to do when I rest at home.

READ: What to Expect When Beijing is Expecting... Rain

Image: ChinaNews