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An aerial view of the flood-affected Kanchipuram district from an Air Force helicopter.
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Volunteers rescue an elderly woman on a flooded street in Chennai.
When I was a student and spent my first twenty years in Chennai, every year at this time, we would get heavy rains, a cyclone - it would all be dramatic but nothing at this level. The Adyar River that has borne the brunt of all the water flowing into the city has been in spate. Unfortunately, the river does not have banks, let alone a flood plain. A flood plain gives a river room to overflow.
Consider this:
1) Most of the southern suburbs sit right on the river banks
2) The airport sits on the flood basin of the river. The second runaway, in fact, was built over the river.
3) The Cooum River is flowing well above the danger mark. The normal flow is blocked by garbage and even settlements in areas where it runs dry.
4) Places like SRM, Satyabhama College, the much-vaunted IT corridor and the Phoenix malls sit on water bodies.
5) The flow of the Oterri canal in North East Madras is also blocked by the bypass that connects NH45 to NH4.
These are just some of the humongously stupid decisions taken in the urban planning but there are many more. The Buckingham Canal, which is meant to act as the drainage for South Madras is blocked not just by garbage and rubble, but an entire colony called MRC Nagar sits on its overflow. Coastal construction norms have been violated and so high tide pushes any water trying to discharge into the ocean right back into the city. The drainage system has not been over hauled in a long time and many of the drains are blocked by garbage and rubble. No one weather event can be taken as an example of climate change, but climate change can cause extreme weather events to happen more frequently.
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Traffic cops clearing the roads after heavy rains causes floods in Chennai.
(Swati Thiyagarajan is an Environment Editor with NDTV)
Disclaimer: The opinions expressed within this article are the personal opinions of the author. The facts and opinions appearing in the article do not reflect the views of NDTV and NDTV does not assume any responsibility or liability for the same.