Background: –
Urban flooding is a problem long associated with Mumbai. With a steady increase in the occurrence and severity of extreme weather events, Mumbai has lost that relative exclusivity, with Chennai and now Bangalore revealing a propensity to be flooded.
As climate change proceeds, cloudbursts and heavy downpours are likely to grow ever more frequent, and urban flooding is likely to become a more frequent, widespread and destructive challenge.
It will not go away by ignoring it. India has to plan how to stay dry in a wetter future.
The modern economy cannot afford to shut down because it rained or because it did not for a long period.
The short point is, floodproofing cities is not just about sparing their denizens occasional bouts of extreme inconvenience but also sustaining economic vibrancy of the city in question and of the country in general.
UN-Habitat: –
UN Habitat is an under-appreciated arm of the United Nations.
Its conference in 2016, in Ecuador, produced a Quito Declaration on a New Urban Agenda, contained a vision of sustainable urbanization; and substantive details on how to achieve it.
It is a document that urban planners would do well to look up, apart from resources available at the UN Office for Disaster Risk Reduction.
Urban Planners: –
In 2015, the government informed Parliament that India had 5,000 urban planners. It is estimated that the number has gone up to some 6,000 now.
Such scarcity of urban planning capacity does not blight developed countries. The state of California alone has 7,750, according to the US Bureau of Labour Statistics, with the US national total coming in at 38,940.
The Quito declaration, later endorsed by the UN General Assembly, commits nations to “promoting the creation and maintenance of well-connected and well-distributed networks of open, multipurpose, safe, inclusive, accessible, green and quality public spaces, to improving the resilience of cities to disasters and climate change, including floods, drought risks and heat waves, to improving food security and nutrition, physical and mental health, and household and ambient air quality, to reducing noise and promoting attractive and liveable cities, human settlements and urban landscapes and to prioritizing the conservation of endemic species”.
Ensuring that cities do not flood, that the water produced by excessive rain would flow away is as much planning and politics as engineering and design.
Thriving cities demand ever expanding residential and office space. The temptation is high to fill up water bodies, canals and drains and build over these.
That must be resisted, not only by conscientious city regulators but by a public sensitized to the need to keep open the channels through which water drains away from their environs.
Keeping the cities open, drained and breathing must become part of the politics of urban governance, political promises before elections.
Storm water drains must be laid out such as to not interfere with the working of the sewage disposal system—otherwise, sewage could back up into places where it should not.
The sewerage network must be planned, in terms of articulation, as well as depth, so that even wastewater from low-lying parts of the town’s topography would drain away, if necessary, into artificial wells, from which water can be pumped out through pipelines, if necessary. Water can be recycled, too, and made fit to drink, with modern technology.
Climate change means that towns can experience both extreme heat and excessive rains. Planning the layout of buildings to avoid the build-up of heat islands will also help build roads with drainage.
Sometimes, to prevent urban flooding, the basic work required might be outside the city altogether: desilting rivers that overflow, inundating towns instead of draining their runoff, and building walls to insulate a coastal town from rising sea levels.
India initiated a global coalition for Disaster Resilient Infrastructure. Indian city and state governments should not be shy about using its intellectual and other resources to prepare against urban flooding, nor the Central government, for that matter.
The cities in which the majority of India’s future urbanites would dwell are yet to be built—India is only one-third or so urban, while China’s level of urbanization is double that.
India would also reach similar levels of urbanization, and fairly rapidly, should economic growth gather momentum.
That would mean building new towns to accommodate another 46 crore Indians.
It is high time India took urban planning and urban governance seriously.