We need to understand why Chennai is reeling under the worst ever floods in its living memory. It is a fact that the rainfall has been extreme – the city has received more than its annual rainfall in just one day. But can this alone contribute to such widespread devastation? And what does this extreme rainfall episode portend for the future?
Each year, we get variable rainfall. This, scientists say, is what will happen as the Planet gets warmer.
We cannot say that Chennai floods are because of climate change simply because no one event is linked to climate change. But the fact is that growing intensity and frequency of weird weather events, including extreme and variable rainfall, is what will happen with climate change. This is what happened in Chennai.
All this is further complicated by the fact that multiple factors affect weather and another set of multiple factors affects its severity and impact. In other words, the causes of devastation following extreme events—like Chennai floods—are often complicated and involve mismanagement of resources and poor planning. So, all this makes for a double-whammy: on the one hand, we are mismanaging our water resources, intensifying floods and droughts. On the other hand, climate change is beginning to make the country even more vulnerable because of increased frequency of extreme weather events.
The same thing happened in Chennai, which is a city that is located at the tail end of all rivers. It has spent a good part of the past two decades squabbling over rights to the Cauvery water, fighting with farmers over withdrawal of water from Veeranam lake and also depleting groundwater aquifers around the city to quench its own thirst. This city, in the early 2000 also did extraordinary work to harvest rainwater from every roof, which improved its water balance.
But in the last 10 years, government’s focus moved from the millions of little water collectors to implementing the one big solution of taking seawater and making it potable. It has set up two plants of 100 million litres per day, but it is struggling to pay for this water, which costs Rs 50-60 per kiloliter. As electricity costs go up, so does the cost of desalination. Chennai water utility MetroWater, till recently the country’s only water agency with balanced books, is now finding itself in the red because of its expensive hardware for supply.
As a result, it turned its back on its water system – its tanks and ponds and drainage network. This city of over 300 waterbodies has built on these systems merrily – all builders see land and not water. The catchments have been encroached upon; drainage systems destroyed. This was a city where not just rivers but canals crisscrossed it as waterways. These were built not just to transport people but to discharge water. But the city thought it could do without drains – it had no use for waterbodies anymore. This is why the flood of 2015 must be remembered. It is human made.
So Chennai needs to do what all cities must. It needs to undertake a detailed survey of the wetlands and then bring every water body and its catchment under legal protection. Currently, the Wetlands Conservation and Management Rules issued by the Union Ministry of Environment and Forests and Climate Change are toothless and meaningless. What is needed is to make sure that city development rules include a comprehensive list of water bodies and their catchment in its classification. Any change of this land use should not be permitted easily or even at all.
But even this will not be enough unless the city values the water this land provides. The Central government should provide funds for water supply to only those cities that have brought their own water sources under protection. The cities must show they have optimised on local water potential before claiming access to water from far away sources. This will reduce the cost of supply by cutting the length of the pipeline, distribution losses and pumping and repair expenditure. The city can invest the saved money in treating sewage, which is what’s polluting the lakes and ponds in the first place. It is this vicious cycle that needs to be broken.
In this age of climate change risk, every water body, every channel and every catchment of rain has to be safeguarded. These are the temples of modern India. Built to worship rain.