A computer-generated rendering of Shanghai's Lujiazui central business district being flooded. Photo: Weibo
A computer-generated rendering of Shanghai's Lujiazui central business district being flooded. Photo: Weibo

Last week a squally thunderstorm struck Guangzhou, China’s third-largest city, and left parts of the modern metropolis of almost 20 million inundated.

After a video clip showing cars floating, drifting and eventually sinking in muddy, surging floodwater was shared a million times, angry Guangzhou residents lashed out at the government’s poor contingency plans and disaster response.

Shenzhen, another boom town in southern China hailed as a tech hub that can give Silicon Valley a run for its money, was also caught in embarrassingly poor shape last summer when a typhoon battered the Pearl River Estuary.

Although the stormy weather caused nothing more than some fallen trees in neighboring Hong Kong, the same typhoon wreaked havoc in Shenzhen, where even a major metro station was partially flooded.

Platforms and concourses of the city’s Chegongmiao Station, a vital interchange for four metro lines, was inundated with floodwater cascading down escalators and stairs.

Floodwater cascades from a staircase on to a platform of Shenzhen’s Chegongmiao metro station in the summer in 2017. Photos: Weibo
A train passed through Chegongmiao station even  though the platform was flooded. Photo: Weibo

And in Shanghai, the only thing keeping the Huangpu River out of the Peace Hotel’s art deco lobby on the city’s bustling Bund waterfront last summer was a concrete flood wall. But surging water levels are posing an even greater threat to the iconic landmark.

When Wuhan, the capital of the central province of Hubei that straddles the confluence of the Yangtze and Han rivers, was hit by torrential rain in July last year, hundreds of roads became impassable as the city received a record 600 millimeters of rain in a week – the amount of rain the whole of Australia gets in a year.

Under the facade of skyscrapers and sprawling metro and subway systems in cities across China lies an inconvenient truth that drainage systems of these cities have failed to keep up with urbanization and more frequent occurrences of extreme weather.

Forests, grass patches, ponds and lakes retreat with sweeping urbanization, and also gone is the natural green infrastructure that could help absorb rainwater or slow the flow of water into the drainage system. The rapid buildup of water simply overwhelms the pumping stations, which can’t work fast enough to release water into the rivers or lakes.

With summer and the rainstorm and typhoon season approaching again, residents of these cities wonder if such flooding will strike again.

In the first half of 2017, heavy rain and floods affected 17.7 million people in 24 Chinese provinces, causing 134 deaths, destroying 24,000 homes, and resulting in a direct economic loss of 30 billion yuan (US$4.7 billion), according to Xinhua.