MUMBAI, July 5 -- Under a red alert issued by the India Meteorological Department (IMD), Mumbai witnessed one of the season's heaviest spells of rain on Saturday, with the red alert set to continue till 8.30 am on Monday. With many locations logging over 200 mm to 250 mm of rainfall (see box), the relentless downpour triggered widespread waterlogging, traffic disruptions, road closures, tree falls and a major road cave-in in Bhandup. But despite the deluge and chaos across the city, no rain-related fatalities were reported. The BMC, citing the red alert, declared a holiday for all schools and colleges for the afternoon session and urged citizens to step out only if absolutely necessary. Sushma Nair, senior scientist, said the intensity of the rain was not unusual for July. "Weather systems such as low-pressure areas and shear zones do form in July, and the quantum of rain is in alignment with these. In previous years, we have seen more than 250 mm to 300 mm of rain on a single day in July," she said. Heavy rainfall between 8 am and 8 pm pounded all three regions of the city. According to BMC's automatic weather stations, the eastern suburbs recorded the highest average of 186 mm, followed by the western suburbs at 168 mm and the island city at 129 mm. The IMD's Santacruz observatory recorded 164.1 mm of rainfall between 8 am and 5.30 pm while Colaba recorded 70.2 mm during the same period. The continuous rainfall, coupled with a high tide of 4.26 metres at 2.50 pm, resulted in widespread waterlogging complaints from several parts of the city. In the eastern suburbs, flooding was reported from Saki Naka, Kajupada, Kale Marg and Ashok Nagar in Kurla, Chheda Nagar Junction in Chembur, and Powai and Bhandup. In the western suburbs, Andheri, Vile Parle, Santacruz, Goregaon East and Dahisar were waterlogged while in the island city, there was flooding in Hindmata, Gandhi Market and near NKES College in Wadala. The rain disrupted both public and private transport, with several arterial roads inundated and barricaded as civic authorities struggled to drain the accumulated water. The BMC said that Mogra Nallah in Andheri, one of Mumbai's major stormwater drains, and several smaller drains connected to it overflowed, causing flooding on roads in the surrounding areas. As a precautionary measure, several roads were closed, including Noor-e-Ilahi service road in Chembur, Veera Desai Road in Andheri, Municipal Market Road, Swami Vivekanand Road in Andheri, Andheri Subway, Huma Mall Junction in Vikhroli, Gandhinagar Junction and Paresh Park Market Road. While most stretches were later reopened, Andheri Subway and portions of S V Road remained closed due to persistent waterlogging. Public transport was also badly hit. Western Railway services were delayed by 20 to 25 minutes due to water on the tracks between Nalasopara and Vasai before normal operations resumed. Photos and videos of waterlogged tracks at Chunabhatti railway station went viral on social media. Central Railway, however, remained largely unencumbered through the day. BEST, meanwhile, diverted buses at 21 locations across the city. The day also saw multiple rain-related accidents, including 17 complaints of wall and house collapses. In one such incident in Govandi's Bainganwadi, a ground-plus-one structure partially collapsed, injuring a 32-year-old woman, who was admitted to Rajawadi Hospital. She is reported to be in stable condition....