Chennai floods: When will we ever learn?

The ongoing torrential rain in Chennai has once again triggered intense debates on how to prevent a repeat of 2015 deluge.

Chennai is no stranger to heavy rains and cyclonic storms as it is very much located along the highly volatile coast of Bay of Bengal. However, massive flooding and water logging within a span of few days of torrential rains has become almost a recurring phenomenon. Global warming, unplanned urban development and unwieldy growth with no hydrological plan are some of the reasons that have been cited as the prime reason for the threat of a massive devastation. How far is this true?

Generally, when there is heavy rain, it is the natural lakes, ponds, tanks, rivers and inter-linked drainage systems that help replenish the groundwater, hold back some water and release the excess to the ocean. And for a state like Tamil Nadu, which is not only home to about 41,127 tanks but is also characterised by a vast network of small water bodies, instances of vast areas getting inundated is indeed puzzling.

Why haven’t the major rivers such as the Cooum, Adyar and Buckhingham Canal, which serve as the main canal water drainage for the city, not able to drain out the excess of rainwater? What has happened to the Pallikaranai marsh which acts as a sponge to soak up the excess of rainwater?

Chennai’s original terrain consists of many lakes and marshy areas. The Centre for Science and Environment (CSE, 2015) reports that the city had more than 600 small water bodies in 1980s. Each of these small water bodies had a natural flood discharge channel which used to drain the spillover. But currently, only a fraction of them could be found healthy. Lamentably, they have not disappeared but have been encroached upon to make way for concrete structures.

What may have been a tank/ pond some 20 years ago is today a site of multi-storey residential or industrial structure. For instance, Chennai’s airport is built entirely on the floodplains of Adyar river; the city’s elevated railway has come up along the stretches of Buckingham Canal. While the actual number of breaches is probably much higher, in general, it has resulted in the gradual reduction in the size of some major rivers and lakes such as Cooum, Adyar, Velachery, Mogappair, Villivakkam and Ambattur.

The Chennai Metropolitan Development Authority in its draft on “Second Master Plan for Chennai Metropolitan Area, 2026” (CMDA, 2008) had clearly warned that considering its importance and drainage system it provides, contiguous swamp area in Pallikaranai should remain conserved, prohibiting development therein.

Sadly, Pallikaranai marshland over the years has become the largest dumping site for solid waste. Open spaces and drainage courses have all become the centre of human habitation. In such a case, where will the rain water runoff go? Pathetically, it has to settle instead on the roads causing extensive flood.

The threat of a catastrophic flooding and encroachments on ecologically sensitive wetlands is not happening in Chennai alone. Recent floods in Mumbai, Ahmedabad, Hyderabad, Guwahati, Kolkata, Bengaluru and Surat clearly demonstrated how most of the urban centres of India fail to manage their drainage channels.

In the process of building a smart city, most of the major cities in India have either completely neglected or have encroached upon the natural reservoirs indiscriminately. As the planet continues to get warmer in the coming decades, countries like India is expected to get more rainfall in less number of rainy days. Are we prepared for it?

As torrential rain continues to batter Chennai, massive water logging in most of the areas clearly indicates that the city has not learned any lessons from 2015. Natural disasters cannot be prevented, but we cannot also sit and wait till the nature unleashes its excess. Better planning is the least that can be done.

A constructive urban planning with proper drainage system is the need of the hour. Governments should not compromise in taking stringent action against encroachments on natural reservoirs, which is reducing water storage capacity.

Tamil Nadu is one among the few states spending large sums of money to clean the rivers and resuscitate the sewage infrastructure. However, all its efforts went in vain primarily because of the civic authorities and land mafia who have been seriously engaged in violating the hydrological cycle of the city. The Standing Committee on Water Resources (2012-13) on “Repair, Renovation and Restoration of Water Bodies”, in its 16th report underlined that most of the water bodies in the country were encroached upon by municipalities and panchayats.

A new legislation should be urgently enacted to make encroachments on water bodies a cognizable offense. In its landmark judgement recently, the Madurai Bench of Madras High Court directed the Government not to grant layout or building plan permission on lands located on water bodies. This is indeed an encouraging signal towards the restoration of dying small water bodies and reducing flood.

With the launch of the massive ‘kudimaramathu’ scheme across the state recently, the policymakers have now realised that the key to resolving both the issues of water shortage and flooding lies in repairing, restoration and renovation of small water bodies which have been largely encroached. Tamil Nadu state can also think of establishing a dedicated Ministry for Water Resources and Flood Governance to improve its governance on water resources and flood on a regular basis.

It is imperative to impose a blanket ban on all construction works in the marshlands. Given the needs, developmental activities in urban areas should be strictly reviewed and approved. Desilting of small water bodies and drainages should be undertaken in regular intervals. The rain water harvesting method that was propagated some years back in the state needs a fresh thrust.

Parks must have ponds and large development areas must have at least a two-acre retention area which will in turn recharge the aquifers. Wherever possible, interlinking of rivers within the state should be encouraged so that the excess of water rather than going waste can be diverted to the water-deficit regions. These initiatives need to be undertaken on a war-footing level. Or else the flood related problems will become a recurring phenomenon.

Narayanamoorthy is Professor and Head, Department of Economics and Rural Development, Alagappa University, Karaikudi, Tamil Nadu. Alli is Senior Assistant Professor, Department of Social Sciences, Vellore Institute of Technology