Low-lying coastal city Shanghai literally means “above the sea.” Yet Chinese officials deny it is most prone to flooding.

The city of 20 million has spent billions of dollars on flood-reinforcement. It’s a low-lying coastal city and is one of the most threatened cities in the world to sea level rise from climate change. Now, a new study shows that the city is more vulnerable than ever. Like clockwork, Chinese officials quickly disavowed the report’s findings, stating that the report did not include new infrastructure investments. While China continues its public denial, they’re spending billions more in infrastructure improvements to help keep the sea at bay.

Shanghai is also sinking. It has sunk 2.5 meters since the early 1900s due to soft soils and China’s insistence on concentrating skyscrapers and other massive buildings.

Exposed to powerful storms, high levels of river discharge, rising sea levels and serious land subsidence, when it comes to coastal flooding, Shanghai is the world’s most vulnerable city.

That’s according to a report by researchers from the Netherlands and UK who studied nine coastal cities around the world.

Dhaka in Bangladesh came in second, while Manila and Calcutta tied for third place.

In response, the Shanghai flood control department points out the study did not take into account the flood prevention measures it has in place.

Hu Xin, deputy director, Shanghai Flood Control Headquarters, said: “On the other hand, we should see that Shanghai has defensive measures in place, such as flood control walls and a city drainage system. I feel that these can basically protect the safety of Shanghai.”

Land subsidence is a major challenge for Shanghai. The city has sunk as much as 2.5 metres over the past century amidst massive urbanisation with increased demand for high rise buildings and underground excavation projects.

To keep that in check, the city government is planning to issue new regulations. All excavation projects will soon be legally required to go through a risk assessment before they can proceed.

China has seen a record number of typhoons and heavy rains this year, with unprecedented frequency and intensity.

And climate change is forecast to further exacerbate the problem, being responsible for a 10 per cent to 20 per cent increase in the number of typhoons in future.

So Shanghai cannot afford to take these warnings lightly.

The incredible economic boom it experienced over the last few decades increases the likelihood for massive financial losses due to ravaging floods - losses that will have widespread consequences for both Shanghai and the world economy.

Yang Dian Hai, Vice Dean, Tongji University College of Environmental Science and Engineering, said: “We have to continue to invest in flood control facilities along the Huangpu river and other coastal regions, as well as our drainage system, to minimise the impact of typhoons and heavy rain.”

Extra measures have also been taken to protect areas of high population density as well as economic projects such as Disneyland which is still under construction.

And compared to the previous five years, the period from 2011 to 2015 will see investment in anti-flooding facilities doubling to nearly US$16 billion.

Via Channel News Asia

Map via Sea Level Rise Explorer

See also, NYTimes excellent article, “Shanghai Struggles to Save Itself from the Sea.”