Mumbaikars can heave a sigh of relief as the city will not witness unnatural high tides this monsoon, like those measuring more than 5 metres in the Arabian sea.
However, there will be as many as 27 occasions in the four month long monsoon which will begin in June, when the sea will rise above 4.5 metres. This is likely to keep officials of the Brihanmumbai Municipal Corporation (BMC) and people living on coastline on their toes. A high tide measuring more than 4.5 metres, coupled with rainfall, could result in water- logging in the city.
The data sent to the BMC, which has been compiled by the Mumbai Port Trust and has been endorsed by the Survey of India (SOI) says that highest tide, measuring 4.80 metres, will occur on September 30 at
1.48 am. “Fortunately, the monsoon season will be drawing to a close by then. Hopefully, the tide will not cause much trouble,” said a civic official.
As most parts of the city are low-lying, a rainfall of more that 50 mm in one hour could cause floods even if a high tide does not occur. However, if the rainfall is moderate, but the tide is higher than 4.5 metres at the same time, low-lying areas in the city will be flooded instantly.
If the rainfall coincides with a high tide then the water logging gets worse as flood waters recede slowly.
Last year, there were 26 occasions when the high tide was 4.5 metres and more. When high tide warnings are issued, the fire brigade and teams from the National Disaster Responses Force (NDRF) line the shores so that any kind of emergency can be tackled.