Prior to the monsoons, the city's municipal commissioner had said the drainage system would be able to deal with about 400 mm of rainfall in a day, as long as there was no high tide.
However, the civic body's website, which authorities had promised would display updated data on the rainfall and flooding across the city, did not do so, leaving city residents to rely on the media for information.
Many schools stayed shut and students were sent home. Some officegoers also preferred the comfort of their homes to braving the journey to their workplaces.
Mumbai was earlier badly hit on July 26, 2005, when rains virtually flooded India's financial capital and life there came to a standstill for a few days, with all major routes submerged in flood water.
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