Recent rains improve Chennai's groundwater levels, Thiru-vi-ka Nagar records biggest rise

CHENNAI: With cyclone Nivar and Burevi bringing heavy rains to the city, the average groundwater level in Chennai this November has improved by nearly one metre compared to October 2020, according to official data from the Chennai Metropolitan Water Supply and Sewerage Board.

Thiru-vi-ka Nagar zone saw the highest increase in groundwater table (2.66m). While groundwater was available at a depth of 5.22m in October, it now can be found at a depth of 2.56m.

Further, Valasaravakkam, Alandur and Ambattur zones also witnessed groundwater levels rising by over two meters.

"One of the main reasons for this is rainfall recorded due to the cyclones. This led to an almost 100 per cent increase in reservoir level compared to last year. We are expecting that the water in reservoirs at the current level will serve the city for 10 months," said a Metrowater board official.

He added that compared to last year, the groundwater levels this year have already been better due to the decrease in commercial and industrial demand. Most of the water now was only diverted for domestic purposes for many months during the lockdown.

The official also said that last year, industrial use coupled with drought conditions made things worse. "Since the water is adequate, people are less dependent on groundwater. So, the level will gradually increase," he said.

Last year after the Metro Water board decreased supply, most residents used borewells to pump out groundwater for daily use.

In zones like Adyar, Perungudi, Kodambakkam, Royapuram and Anna Nagar, which usually witness water shortage during most summers, water level rose by 1.91m, 1.22m, 1.33m and 1.87m respectively.

The groundwater continues to be the lowest in Royapuram zone. While in October, it was available at a depth of 6.44m, it is now available at 4.89m.

Notably, Niti Aayog's Composite Water Management Index, released in 2018, had highlighted that Chennai will run out of groundwater by 2020. The report's claims were disputed since they were based on outdated data. 

The lockdown and the recent rains caused by two cyclones seem to have helped improve Chennai's groundwater level. Also, after last year's drought, a lot of people installed Rain Water Harvesting systems in their apartments/homes in a bid to recharge the groundwater table.