CHENNAI: A total of 13 districts in Tamil Nadu have recorded a fall in their groundwater level in May compared to May last year, according to data compiled by the Water Resources Department (WRD) for 37 districts barring Chennai.
The sharpest fall was witnessed in the delta district of Thanjavur, where the groundwater level has gone down by 2.51 metres. While the availability was at 1.9 metres in May 2024, it dropped to 4.41 metres in May this year. This is despite ample rain in the monsoon and Karnataka releasing more water in Cauvery due to bountiful rains, which ensured adequate release of water for irrigation in the delta region.
A senior official from WRD told TNIE that despite availability of river-based irrigation systems in the delta and western regions, many of the farmers still use borewells due to easy availability, leading to faster depletion of groundwater levels.
In Erode and a few other western districts, officials said farmers prefer growing high-value crops such as turmeric, betel vine, banana, and vegetables, which are water intensive. As a result, the use of groundwater in these areas is very high, they added.
In the remaining districts, the groundwater level either remained same or marginally improved, according to WRD. Studying Chennai’s groundwater levels comes under the purview of Chennai Metropolitan Water Supply and Sewerage Board.
Officials said that though awareness programmes are conducted to explain the adverse environmental impact, checking over-extraction of groundwater remains a major challenge for the state government. Besides, the growing population and increasing need for more water are also reasons for groundwater depletion, an official said.
It may be noted that the WRD has presented a proposal to carry out village-level study of aquifers in three districts for a more granular understanding of the issue so that localised plans can be devised to tackle the issue.
“To improve the situation, we (WRD) have taken steps such as building check dams, and desilting ponds, canals, and lakes to help recharge groundwater,” the official added.
V Ravichandran, a farmer from Tiruvarur, said that changing weather patterns and erratic rainfall have worsened the situation and have made farmers to rely on groundwater, which is also depleting fast. “Nowadays, we are facing irregular monsoons and climate change issues. In earlier times, we used to get rainfall spread over two to three months during the monsoon. But now, we see heavy downpours in a short span. This also affects groundwater recharge and leads to depletion,” he added.
He urged the state government to take effective steps to promote rainwater harvesting across the state. “It is also essential to desilt small waterbodies like ponds and lakes to improve water storage and groundwater recharge,” he added.