Zhang called on the authorities to reflect on the infrastructure and city planning and hold accountable departments that fail to perform their assigned function according to the emergency response plans.

Once again, the question of the quality of the capital's infrastructure, especially its drainage system that has long been criticized as insufficient to cope with the rainfall in recent years, was brought to the front stage.

During the downpours on July 21, transportation in the lower areas of the city was paralyzed, especially in some underpasses with poor drainage systems. Deep water was logged at 52 sites in downtown areas, including many underpasses.

Many skyscrapers have been erected and densely populated communities have been built in recent years due to a buoyant property market. However, the drainage system has not been upgraded accordingly and remains at a low standard, city planning experts complain.

According to the Beijing Water Authority, Beijing's drainage system was designed to cope with precipitation of 36-56 mm per hour. However, the city received 170 mm of precipitation on average on July 21, while the urban area saw an average of 225 mm during the 16-hour deluge.

Beijing's drainage system is made up mainly of old facilities. Some key drains even date back to the Ming Dynasty (1368-1644). When rain is too heavy, administrators have to order the opening of drainage covers to allow floodwaters to subside faster.

"Beijing's drainage network is already outdated, although a lot of repair work has been done to maintain it," said Zhang Junfeng, founder of the non-government water resource watchdog Happy Water Journeys.

Dai Shenzhi, a professor at the College of Architecture and Urban Planning of Shanghai-based Tongji University, said that as there is less natural vegetation to absorb rain, more urban development increases the risk of flooding. "It would be much more feasible to allocate areas of wetland to be used as overspills to guard against floods," Dai said.

Echoing Dai's views, Zhang said that the country's obsession with rapid development has many local governments paying little attention to building wetlands, as it won't result in economic benefits.

The design of underpasses in Beijing has also become the target of public complaints.

"The design standards of underpasses are poor because they were constructed in the 1980s," said Zheng Jiang, Deputy General Manager of Beijing Drainage Group in a press release on July 22. "It makes our underpass drainage system vulnerable."

According to him, many of Beijing's 78 existing underpasses have a limited pumping capacity and are capable of draining away water only if the rainfall is less than 30 mm an hour, making traffic jams in rainy weather a regular sight.

Pan Anjun, Deputy Director of the Beijing Water Authority, said that thorough examinations of underpasses will be conducted, and upgrading plans will be made for every one of them to improve drainage.

According to a report released by the Beijing Drainage Group in early July, all the existing underpasses will be reconstructed by the end of 2015. More powerful pumps will be installed and adjustable reservoirs will be built for some underpasses.

"One solution to improve the poor drainage system in Beijing is to gradually upgrade the underground conduits and design standards," said Liu Dongwei, chief architect of the China Institute of Building Standard Design and Research. "But it's not a job that will be completed soon."

Liu suggested that the new design standards should be implemented as part of the whole city development plan, and more permeable materials should be adopted in more communities.

"As a megalopolis, Beijing is a combination of old and new," Mayor Guo Jinlong told national broadcaster CCTV on July 22, the day after the torrential rain. "The storm proved that the city's infrastructure facilities are still weak. We will continue to update our emergency plans, improve the construction of infrastructure facilities, upgrade our ability to mobilize rescue staff and promote people's safety awareness in the future."

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