No lessons learnt as Mumbai floods

Source : SIFY
By : Varun Sukumar
Last Updated: Thu, Aug 31, 2017 18:05 hrs

In July 2005, Mumbai received over 900 mm of rainfall on a single day and the city was flooded. On Tuesday, it received about 350 mm of rainfall and the result was the same. A large sprawling metropolis with the richest municipal corporation in Asia in charge of it is not able to learn its lessons from the past; and events like Tuesday and July 2005 will likely repeat.

The Brihanmumbai Municipal Corporation (BMC) made the argument that the drains aren’t equipped to handle large amounts of water. In other countries, taking the USA as an example, after Hurricane Sandy devastated the North East, building codes in New York were revised. The question asked for Mumbai is: why wasn’t a comprehensive plan put in place after 2005?

A majority of people living in Mumbai reside in suburbs. These are served mostly by roadside drains and open drains which are mainly used to dump tones of garbage into. As a result of these drains flowing several kilometers through congested localities before discharging into the sea through outfalls which are below sea level, the water rushes into the city.

The Hindu editorial stated the need to improve infrastructure and protocols in urban centres –

“The return of the deluge to Mumbai and the paralysis suffered by the city bring up the question of why Indian cities are unable to improve their resilience to extreme weather events. As the nucleus of financial activity, Mumbai’s losses naturally have national implications.”

“Beyond the political wrangling on bad management, such extreme weather events trigger valuable research and analysis on developing better prediction and management systems. There should naturally be an inquiry into whether the reforms proposed over time, ranging from clearing of drainage channels and removal of encroachments to the creation of holding ponds to temporarily store large volumes of water, gained any traction.”

The editorial points out that the take away from Mumbai are important for other cities as well citing an example –

“Numerical weather prediction has consistently improved. Researchers from IIT Gandhinagar published a forecast on social media warning of 100 mm-plus rainfall for the region on August 29, four days ahead. These remarkably accurate models open up possibilities for authorities to evacuate vulnerable sections early, residents to stock up on essential supplies and disaster management authorities to review options.”

“If there is a single priority that every city needs, it is to reopen the veins of natural drainage that have been callously built over. Mumbai this year and Chennai’s disastrous flood of 2015 underscore that lesson.”

The BMA Chief Ajoy Mehta in an interview with DNA said that there’s a limit to the preparations saying, “There is a limit to the preparations that you can make. Now your infrastructure is prepared for 50 mm rain per hour. But when you end up with six times of that, things are going to get strained.”

Former president of the Practicing Engineers Architects and Town Planers Association (PEATA) commented on the situation saying, “I fail to understand why desilting of drains has to be an annual affair? Why can’t they be cleaned and desilted by the BMC regularly? Their cleaning happens only once a year, and that too before the monsoon. Nobody knows how much silt is removed and where is it dumped.”

The Hindustan Times editorial called for authorities to be held accountable and that more excuses won’t do –

“The weatherman had sounded a warning three days ago and repeated it on Monday. More than enough time to prepare. But that is the crux of the problem. We never learn from our mistakes. After the great deluge of July 26, 2005, when 944 mm of rain fell in 24 hours, there was a lot of talk that the authorities would be better prepared the next time around.”

“The railways say they can’t do anything if the tracks are flooded. Really? In this day and age can’t they build a better drainage system? The railways blame the civic body and the civic body blames the weather. Where does that leave the Mumbaiite? This tactic of passing the buck is endemic across the country.”

To the point of learning from the past regarding the 2005 floods; the state and civic bodies looked into a few projects. An important one was the decision to implement the Brimstowad (Brihanmumbai Storm Water Drainage) project. Recommendations were made to construct detention basins for flood water and to clearly mark flood-prone zones. However, this among other projects like preparing maps for a flood modeling system were never taken up or were left incomplete.

The Indian Express editorial stated that monsoon warnings are not taken seriously; commenting on the changing climate patterns and flood governance in India still being about ad hoc relief measures –

“The weather patterns during the rainy season — days of intense downpour sandwiched between spells of dry weather — raise questions about our understanding of the monsoon, as well as about the ways in which we prepare for and deal with floods.”

“Climate scientists have been issuing warnings about such extreme rainfall for more than a decade. A 2013 Intergovernmental Panel on Climate Change report warned that Mumbai remains vulnerable to rainfall of the kind that led to the 2005 flood…”

“Flood governance in the country has not gone beyond ad hoc relief measures and building embankments. It’s also clear that we require fresh thinking on how to prepare for the monsoons and deal with floods.”

The Mumbai floods points towards a troubling pattern in severe rainstorms this year. In Assam, lakhs were affected, lakhs of hectares of crops were damaged as the Prime Minister announced Rs.2000 crore relief package for various flood-mitigation measures in the Northeast. In Bihar, over 500 dead, Gujarat over 200 dead, Bangalore also witnessed its heaviest rainfall in decades.

Solutions can be general in terms of large urban cities such Mumbai, Bengaluru and Chennai and also tailor made for particular cities given the unique nature of the geographical location of each cities. Coastal cities are the most vulnerable; as pointed out by the 2013 Intergovernmental Panel on Climate Change report, more than 2.5 million are exposed to coastal flooding in Mumbai alone, which is projected to increase to 10 million over the next few decades.

More columns by Varun Sukumar