However, the subway system was largely unaffected, aside from being swamped with people desperate to get home and unable to use cars, buses or taxis.
The city received about 170mm (6.7 inches) of rain on average, though a township in Fangshan district was hit by 460mm (18.1 inches), said Xinhua.
The Beijing city government said on its website it is working to get the metropolis back on its feet, but reminded people to prepare for further bad weather.
"The weather forecasters say that from late July to early September this city is prone to flooding, and there could be further large-scale storms or extreme weather," it said.
Many residents took to China's popular micro-blogging site, Sina Weibo, to post dramatic pictures of the storm. Some complained the city should have been prepared, especially since the government had issued a severe storm warning the day before.
"It was forecast early on that Beijing would get torrential rain, so why were pumps and other facilities not prepared in time?" complained one user.
At least one good result came from the storm. The official pollution index, which had showed an unhealthy rating before the storm hit, registered "excellent" on Sunday, with the air noticeably free of its normal acrid smell.
Intellpuke: You can read this Reuters article, filed from Beijing, China, in context here: www.guardian.co.uk/world/2012/jul/22/beijing-rainfall-heaviest-china