Mumbai: Amid warnings of heavy rains in Mumbai and adjoining areas, the Brihanmumbai Municipal Corporation (BMC) has alerted disaster management units and fire brigade and asked other departments such as BEST, Education department & Health department to remain on standby. "The Education Department has been asked to identify locations for emergency shelters. BMC has marked residential areas near the Mithi river and is ready for evacuation if the situation worsens. BMC has started coordinating with NDRF, Coast Guard and Navy. They'll be available to help if needed," the BMC said on Friday, news agency ANI quoted.Rains brought the city to a standstill earlier this week after local train operations were halted for a brief period and resumed after waterlogging. Chief Minister Uddhav Thackeray had already alerted the rescue agencies and asked them to carry out preventive evacuations from low-lying areas.Earlier today, the India Meteorological Department (IMD) issued an orange alert for Mumbai and predicted heavy to very heavy rains in the Maharashtra capital. Waterlogging, traffic snarls brought the city to a standstill, even as the civic administration installed 458 pumps at various locations to pump out the rainwater.Mumbai Mayor Kishori Pednekar said that work is underway to cover 73000 manholes in the city. "There are 73000 Manholes in Brihanmumbai Municipal Corporation (BMC) jurisdiction. Most of them already have protective grills and we are trying to cover all the manholes in the city. Yesterday and say before which incidents happened were due to the fibre protective cover of manholes. We are now planning to put manhole cover with lock facility to avoid theft of covers," she said.According to the IMD, Mumbai's Colaba received 23.4 mm rainfall while Santacruz witnessed 107.4 mm rain during the last 24 hours.