As I prepare for travel to Mumbai, I cast an eye on monsoon forecasts, particularly when they coincide with high-tides.
Excerpt from notice from the US Consulate in Mumbai.
During the monsoon, most flooding occurs during high tide. Mumbai’s drainage system is designed to run off into the Arabian Sea. If a major storm occurs during high tide, the rainfall backs up and flooding occurs. Particular concern should be paid during the days listed in the table below. … if there is heavy rain (during these dates), the possibility of the city flooding is very high. Sluice gates, which funnel flood waters from the city to the sea, are also closed on these days, increasing the possibility of flooding …
The Municipal Corporation of Greater Mumbai site is very informative and lists the 27 days during this Monsoon season when tides are expected to crest 4.5 meters (14.8 ft). See entire list of Mumbai High Tide Dates and Times
Highlighted are the 11 days when the high tides will crest over
4.8 meters (15.75 ft). In July of 2005, when heavy rains coincided with high tides, caused city-wide flooding and killed over 400 people, the tide had crested at 4.84 meters. So these are dates you should prepare for.
With four of these days behind us in June, we have seven remaining days ahead of us. Four days in July are ALL over 4.84 meters and the city is very vulnerable. Further on July 23 and 24, the tide is expected to crest at 5.01 and 5.05 meters (16 ft), the highest in nearly a 100 years.
In August, the high tide days just precede the Ganesh Festival starting on Aug 23rd. We will have to do our shopping and other preparations earlier in the day. Particularly on the night of Aug 22nd, when we bring the Ganesh murthy to our home; we will have to do it earlier in the day.
Great days to work from home! Avoid travel on these and shoulder days too, as the Mumbai airport runways are notorious for getting water-logged.
Remaining 7 Dangerous Days of Monsoon
Date Time Ht of Wave (meters)
22 July 2009 1240 hours 4.85
23 July 2009 1323 hours 5.01
24 July 2009 1403 hours 5.05
25 July 2009 1443 hours 4.94
20 Aug 2009 1216 hours 4.81
21 Aug 2009 1257 hours 4.94
22 Aug 2009 1334 hours 4.92
Add these to your calendar and be careful.