Is it natural disaster or man-made misfortune? A heavy rainstorm which started on Saturday afternoon and lasted until the small hours of Sunday morning has turned much of Beijing into a giant swimming pool, leaving 37 people dead and causing widespread chaos. The authorities claimed the rain is the heaviest to hit the city of nearly 20 million people in six decades, indicating that it is a natural disaster. But for many residents, it is also a man-made misfortune of a sort which could have been avoided but will continue to plague the metropolis unless the city greatly improves its inadequate infrastructure and sewage system, and puts in place an efficient emergency management system. Weather forecasting is notoriously unpredictable, but mainland meteorologists got it right when they issued a warning on Friday that heavy rain would hit much of northern China, including Beijing, in the coming days. Beijing officials boasted to the media on Friday that they were fully prepared and promised that they would station workers under every motorway overpass, where the low-lying land is usually flooded whenever it rains, and that they would pump water to make sure the roads were not flooded, to ensure smooth traffic. Alas, the television images showed a different yet familiar story: the low-lying areas under most of the city's hundreds of overpasses were flooded, with cars or even buses stranded in the waist-deep or higher waters. The state media have provided blanket coverage on how city officials mobilised more than 100,000 people, including soldiers and policemen, to conduct rescues, and praised those selfless people for saving lives. But great damage has already been done, with loss of lives, and more than 80,000 people stranded at Beijing airport. The saddest part is that if past experiences can be a guide, as business returns to normal after the storm, city officials will most likely move on with little review or soul-searching, conveniently attributing everything to 'natural disaster'. Although Saturday's heavy downpour was unusual, the fact remains that Beijing is often paralysed because of rain, as it was last summer, even though the rain was much lighter then. Obviously, the inadequate and underfunded sewage system cannot cope. On the national level, Beijing is not alone. Almost all the major mainland cities face a similar challenge. Outside visitors may marvel at the gleaming towers and elaborate overpasses in the cities of Beijing, Wuhan , and Shanghai, rivalling the metropolitan areas of London or Paris. Looking deeper, those mainland cities are nowhere close in terms of city planning, particularly of the underground sewage system. The mainland authorities may spend billions of yuan each year to lay the networks of electricity, gas, and telecoms underground but, usually, spend little on improving sewage systems. According to previous media reports, some of the sewage system under the centre of Beijing was first laid in the Ming dynasty (1368 to 1644) and has not been expanded very much. An irony often cited in state media reports is that the city of Qingdao in Shandong boasts an 'advanced' sewage system, compared to other cities, because it was designed and laid out under the supervision of German engineers when the city was a German concession more than 100 years ago.