A flood of lessons
Rasheed Kappan, DH News Service, Bengaluru, Oct 22 2017, 1:07 IST
Unprecedented in scale, record rains this season severely exposed the city's poor infrastructure.
Flash floods, record rains, deaths and miseries unprecedented in scale, Bengalureans have seen them all. A dramatic weather change played havoc on the roads and in their homes alike. Now, when the monsoon fades away, isn’t it time to ask what went so horribly wrong. Why, despite warning, the authorities were caught so unprepared.
Armed with a hundred telemetric rain gauges spread across the city, the Karnataka State Natural Disaster Monitoring Centre (KSNDMC) insists it had delivered regular, location-specific rain alerts through its Whatsapp group ‘Be Ready Bengaluru.’ That group has BBMP ward-level engineers, corporators, joint commissioners of the Palike, BMTC, BWSSB, traffic police and fire forces.
But, as one looks back, such forecasts made no difference to Bengalureans. Over a dozen people died, hundreds of localities were flooded for days. Roads are in a mess, drains clogged and in total disrepair. The message is clear: Despite giant strides in technology, the country’s IT hub has still not perfected a functional rain alert mechanism. Clearly, the agencies responsible knew what was coming, and did nothing.
The pre-monsoon showers, the onset of the Southwest monsoons and seasonal forecast by the Indian Meteorological Department (IMD) had given agencies here enough time to prepare. Yet, the enormity of this year’s rains caught them totally unaware. The skeletal measures lay completely exposed.
Climate change definitely worsened this year’s monsoon, analyses KSNDMC director, Dr G S Sreenivasa Reddy. “Studies clearly indicate that extreme weather events have increased everywhere. This year, in the entire tropical belt, temperatures have risen by 2-3 degrees. With rise in temperature gradient, pressure gradient dips. Moisture-bearing clouds move towards low pressure areas,” he explains.
The combined effect of this change and monsoons has had a dramatic effect on Bengaluru. In the past two months alone, the city has received rain exceeding the annual normal of 900mm. Between August 1 and October 16, the cumulative rainfall stood at a staggering 919mm. Koramangala received the highest at 1,216mm, while Marathahalli recorded a high of 1,212mm rain.
On October 14, the city’s Nandini Layout recorded 95mm rainfall in one hour, making it the wettest day in decades. From a 24-hour standpoint, the wettest day for October still remains October 1, 1997, when the entire city received 178.9mm.
It is clear the scenario could only get worse from here. No weather monitoring agency, KSNDMC or IMD is prepared to predict next season’s rainfall will be any different. This implies there is no alternative but to boost the coordination between the weather and civic agencies and prepare for the worst.
To analyse and predict weather conditions, KSNDMC has a dedicated website (bengaluruvarnamitra.info) accessible to all. Mobile notifications go to every government official and members of the public who register for the site. But to really make a difference, the website’s real-time data should be accessed through a mobile App.
A student-teacher team from the M S Ramaiah Institute of Technology is currently working on the App. However, KSNDMC wants to accelerate the process, through corporate partnership. As Reddy informs, the application should be out by April or May next year.
The objective is pretty straightforward: To alert people about rains in the quickest possible way, and with as much accuracy as current technology permits. As a city commuter, Suraj Mahapatra put it, “I should be able to look at the rain forecast / flood data overlaid on a Google map, and make my commute decisions accordingly. I could then avoid taking a particular road by also looking at the traffic data, which is already there.”
Flood Watch Groups
But the bigger responsibility would be on the civic agencies to ensure every city road motorable. Bottlenecks will have to be identified and infrastructural issues such as road repairs, drain-remodeling and desilting completed well before April / May. Weather experts also suggest forming Flood Watch Groups at the local level.
Designed decades ago, the city’s storm water drains (SWDs) are ill-equipped to handle cloud bursts that can generate rainfall of about 100mm. That happened at Mahalakshmipuram on August 14. But since such rare events are bound to turn less rare in the coming years, the city will have no choice but to overhaul its drain network. The glacial pace of the SWD remodeling project will just not do.
A non-structural solution would be to find ways to harvest the flood waters, seeing it as a resource not to be wasted. Reddy says nearly 37% of flood water can be reduced if at least 50% of buildings in the city go for Rainwater Harvesting techniques. “Even without BWSSB water, the city can then sustain for six months.”