Residents of the city, which Indian Prime Minister Manmohan Singh said in 2004 could become a financial centre rivalling Shanghai, were forced to wade through ankle deep water as workers battled to clear drains clogged with plastic bags and other debris.
The Mumbai municpality was meanwhile lambasted by the High Court for its failure to tackle flooding of low-lying areas caused by the monsoon rains which have been lashing the city since Saturday.
The court, responding to a public interest litigation, said it appeared from the massive disruption of normal life in the city -- especially on Tuesday -- that the municipality had done little planning for coping with heavy rains.
Last July, the corporation came in for severe criticism from residents and politicians for being caught unprepared for flash floods which killed more than 400 people in the teeming city of 18 million people.
The weather office said Mumbai had 44.4 centimetres (17 inches) of rain on Tuesday and another 7.5 centimetres (2.9 inches) by mid-morning Wednesday.
It warned more "heavy to very heavy showers" were on the way and that "extremely heavy" rains were also possible.
The authorities said they had at least managed to keep trffic flowing.
"Our staff continues to be on around the clock alert. We could see another wet day today, however none of the major roads are waterlogged and traffic is moving normally," Mumbai's municipal commissioner Johny Joseph told AFP.
Mumbai police chief A.N. Roy said the death toll in the rains since Saturday had risen to seven.
Two people were electrocuted while two street dwellers were crushed by a falling tree. Three children drowned while playing in well in a northern suburb, he said.
The deaths brought to at least 232 the number who have died across India as a result of rains and high winds since the start of the monsoon in May.
Schools and colleges remained closed Wednesday but attendance in offices was reported better than at the beginning of the week.
"The situation was a little better getting into work," said 30-year old Ashish Deovasthali, who works with a private sector bank in low-lying Byculla area of the city.
"There was marginal flooding but I don't think I'd worry too much."
There was good news for travellers after Tuesday's massive disruptions with most train services and flights in operation and running with delays of 15 to 20 minutes Wednesday, railway and airport officials said.
But incoming long-distance trains were running one to three hours late, reports said.
Meanwhile, NDTV news channel reported that some 4,000 people had been evacuated from several districts of neighbouring Gujarat state following heavy rains there.