As China prioritizes the economic development of its huge metropolitan centers such as Beijing and Shanghai, the risks posed by flooding and land subsidence (sinking) have been overlooked by local officials.

A recent study in the journal Natural Hazards suggests that Shanghai is the most vulnerable city to flood risks when compared with eight other coastal metropolises built upon rover deltas across the globe, including Osaka (Japan), Manila, Casablanca (Morocco) and Dhaka (Bangladesh).

The results of this study are especially sensitive to Chinese officials since only a month ago the capital city of Beijing suffered a devastating flood that killed nearly 80 people and damaged or destroyed 8,000 homes.

The study was conducted by a team of scientists from the UK and the Netherlands, who developed a Coastal City Flood Vulnerability Index (CCFVI) based on exposure, susceptibility and resilience to coastal flooding. Measuring not only a city's physical attributes, the CCFVI index also considered social, politico-administrative and economic factors.

The survey found that Shanghai is facing high levels of river discharge and serious land subsidence, and is at great risk of suffering from natural disasters like typhoons, rainstorms and floods. With too few shelters for its dense population, too little public education and training on flood prevention, and a relatively ineffective institutional system for crisis management, Shanghai is the most vulnerable large coastal city in the world to the risk of floods.

This study did not come as a surprise, as many scientists worldwide have already warned against China's rapid urban developments -- citing that the glittering new skyscrapers and residential towers may be dangerously susceptible to natural disasters.

Beijing's flood disaster in July was viewed by many as proof that Chinese cities are ill-prepared for such catastrophes.

While the thunderstorm did bring the highest record of rainfall recorded in Beijing since 1951, the city's infrastructure and flood prevention programs were called into question, considering the magnitude of the damage.

Qi Hong, the mayor of Fangshan, the district in Beijing that was hit most severely by the floods, admitted that the flooding exposed problems within the city's infrastructure.

For example, Zheng Jiang, deputy general manager of Beijing Drainage Group, revealed that the Beijing's design standards for its underpasses were completed way back in the 1980s -- the failure of these underpasses to adequately drain water during the heavy rainfall were among the many factors behind the high number of casualties.

Distressed by Beijing's lack of preparedness, many bloggers expressed their discontent with the government, claiming that its priorities are backwards. One of them posed a question to the national government: asking if $42 billion can be spent on hosting the 2008 Summer Olympics, then why can't a portion of that budget be spent on improving the city's water drainage system?

The local Shanghai newspaper, Oriental Morning Post, complained that China has always "focused on the development on the surface and neglected those beneath the surface, emphasizing the overall aesthetic of the city through buildings and architectures, but not the drainage or sewer systems that go beneath it."

Calling its government "superficial and lacking substance," the newspaper was quoted widely on the internet by journalists and commentators.

Shanghai, with a population of 23 million, is even more populous than Beijing (20 million). It is a major financial center and has one of the busiest sea ports in Asia.

Shanghai has also been undergoing a series of fast-pace, large-scale construction, making it vulnerable to severe land subsidence that has caused several deaths as pedestrians unexpectedly fell into cracks on the sidewalks.

According to TIME magazine, as progress continues on Asia's tallest skyscraper, the Shanghai Tower, the problem has manifested itself in sidewalk cracks nearby, captured and posted by users of the Twitteresque micro-blogging site Sina Weibo, then published by ChinaSmack.

This latest study by Natural Hazards, along with many other similar reports, puts a glaring focus on how China's rapid expansion and economic development has outpaced its concerns for safety and the environment.