By Li Qian | 2012-7-25 | ONLINE EDITION
THE Beijing Drainage Group Co Ltd yesterday blamed the planners of the capital's drainage systems after questions were raised about the city's ability to cope with flooding after the torrential rainstorm claimed 37 lives over the weekend.
The company said the pump stations serving 90 overpasses citywide that were built last century were based on the experience of the former Soviet Union, where more than half the country received less than 400 millimeters of rainfall each year.
The then professionals involved didn't anticipate such a downpour as happened at the weekend -- the heaviest the city has seen in 60 years. The pump stations couldn't cope and that was what had caused the severe flooding, the company said.
Chen Ming, the company's manager, said 74 of the pump stations would be renovated within three years with each able to handle up to 50mm of rainfall per hour, according to Xinhua news agency.
But he admitted that the future pump stations would still not be capable of dealing with such fierce rainstorms. "It needs overall urban planning to fix the root cause and to have a perfect drainage system," he added.
Professionals have suggested the authorities learn from Japan and Britain and build reservoirs underground to collect the rain or set up greenbelts a little below ground level naturally soak up the water and, at the same time, irrigate the plants.
Urban flooding has been a chronic problem in China. This summer, rainstorms and flooding have wreaked havoc in many cities, including Guangzhou, Chongqing and Shenzhen.
However, Xinhua said it was embarrassing that many ancient drainage systems still worked and that cities had to rely on these "antiques" to resist the floods.
In a royal palace near the capital's Beihai Park, the roads were never submerged under waist-deep water thanks to drainage systems built in the Ming (1368-1644) and Qing (1644-1911) dynasties.
Nine wells inside the palace collect the rain and link to an underground river which surrounds the palace and flows to the then city moat. In addition, the paving was laid in such a way that rainfall could easily find its way into the soil beneath, Xinhua said.
Many other historic places, including Tian'anmen Square and the Temple of Heaven, have the similar system and weren't submerged.
Besides the outdated drainage network, experts also believe the floods are largely the result of urbanization, with vast networks of roads and the elimination of greenbelts decreasing some cities' ability to cope with heavy rain.
Sheng Minzhi, an engineer at the Hangzhou Planning Bureau, said the mass construction of tall buildings and underground parking lots in some cities had slowed the rate at which the ground could absorb rainwater, Xinhua said.