This monsoon,Mumbaikars will have to brace for 21 days of high tide when the tide levels will be higher than the danger mark of 4.5 m. However,the number of high tide days as well as the height of the highest tide this year is less than last year. There were 27 high tide days last monsoon with the highest tide of 5.05 m. This years highest tide is expected to be on June 6 at 1:52 pm at 4.89 m. Chances of flooding and inundation are much higher when the tide level above the danger mark coincides with heavy rainfall. This year,six days each in June,July,August and three days in September will see a high tide of 4.5 m and above. The number of high tide days over the past few years has been consistent. There were 19 such days in 2008,22 in 2009,26 in 2010 and 27 in 2011. Chief disaster management officer of the Brihanmumbai Municipal Corporation (BMC),Mahesh Narvekar said the disaster management team will be extra cautious on these 21 days. Out of these 21 days,June 5,6,7 and July 5 will witness tides higher than 4.5 m. We hope rainfall on these days is not very heavy,otherwise there are high chances of flooding,specially in areas like Dadar chowpatty which are prone to flooding, he said. In case of tides higher than 4.5 meters,BMC closes the outlet of storm water drains to avoid sea water from being pushed into the city. This creates a flood-like situation if drains are not cleaned enough to hold water before and during the tides. Problems usually start arising when rainfall exceeds 100 mm on days when high tide is higher than 4.5 m. During the July 26,2005 deluge,high tide was 5.01 m and the rainfall recorded was 944 mm in Santacruz.
