Megapolis Chennai: Let’s live with water

CHENNAI: Getting close to December for Chennaiites is equal to watching one of the slasher movies of the 90s. We’re certain that we are in for some spine chilling events yet we remain unprepared for what’s coming.

Every time before the monsoon season starts, we see roads being dug up for some form of construction or repair works, home owners racing against time to create some sort of barricades to stop rain water entering their homes and so on.

However, despite all prevention initiatives and preparatory works, for the past 10 years, the city has been getting flooded at least once in every year. The truth is we’re unprepared and we can never be prepared enough.

We live against the water – the fundamental element we are made of. It is elementary-level science that water flows from higher ground to lower ground, and it would reach its intended place no matter what. Still, a majority of Chennai’s economically active localities, like T Nagar and Nungambakkam, were built on lakes and water bodies. Lakes were levelled up, link canals were encroached upon and even marshlands were being gobbled up.

Global warming is a reality, and there’s not a proverbial off-switch in sight. Due to the rapid ascension of climate change and climate anomalies, Chennai will get its majority of rains in just a few days during the monsoon.

In other words, it will be inundated in a short span of time. Remaining last lakes would fill quickly and soil, wherever not covered by concrete, will saturate rapidly. So, the time has come for the city to live with water; not against it.

The lakes that still exist should be protected and new lakes should be created wherever possible. More importantly, linking canals must be reclaimed. Though the recent developments like restoration of lakes under Smart City Mission and creation of new water bodies on Madras Race Club land, the measures are minuscule when compared to the force of the mighty water.

To put in a perspective, Chennai roads and streets held around 67 TMC (Thousand Million Cubic feet) of stagnant water after heavy rains induced by Cyclone Michaung in January-February of 2024. During the cyclone, the city received 47cm of rainfall in 48 hours.

For better understanding, Cholavaram, Red Hills, Kannakottai Thervoykandigai, Chembarambakkam and Poondi – reservoirs that supply drinking water to Chennai have a total storage capacity of only 11.75 TMC. Moreover, 67 TMC is around two-third of total storage capacity of Mettur Dam, which is 93 TMC.

While the government can concentrate on creating lakes, ponds, sponge parks and others, residents can also contribute by constructing rainwater harvesting structures and maintaining it so that some of the stagnant water can be sent underground and can be extracted later.

Recent studies indicate that heavy rainfall events (more than 10 cm) in the country have increased by more than 10% each decade and the number of heavy rainfall events (more than 15cm) doubled during the last 70 years. Moreover, during the monsoon, rainfall does not occur all the days of the season and all 24 hours of the day. It occurs only in a few hours.

So, Chennai should learn to enjoy the few hours of rain as rain is the only succour to the heat-hit city and use the rest of the time for preparation.