CHENNAI: Tamil Nadu is staring at a serious water crisis this summer. While on the one hand, the northeast monsoon failed the State, on the other groundwater levels have dipped remarkably. A whopping 20 out of 32 districts in the State are in the red and the depletion rate is recorded as high as 4.32 meters in Perambalur district.
Analysis of December 2018, data – released by the State Ground and Surface Water Resources Data Centre of the Water Resources Department – reveals that the situation is much worse than the peak summer months of April-May. For instance, the water table in Dharmapuri was 11.45 metres in May, which went up 12.13 metres in December.
This is the case in most of the districts where the monsoon has failed. Though, the data does not disclose Chennai’s groundwater levels, it is obvious that the capital city will be at the top among the worst-affected districts as the monsoon season ended with a 55 per cent deficit in rainfall.
Measurements taken from the observation wells show significant decline in the districts of Perambalur, Thiruvannamalai, Salem, Dharmapuri and Ariyalur. In Perambalur, the groundwater levels dropped from 6.74 mt to 11.06 mt. The levels in neighbouring districts like Kanchipuram and Tiruvallur have also depleted in the order of 2.39 mt and 1.64 mt, respectively.
On the other hand, districts like Coimbatore, Erode, Madurai, Nagapattinam, Tirunelveli and few other delta districts, where the monsoon has been active, although were devastated by Cyclone Gaja, recorded marginal rise in groundwater levels. Coimbatore was the highest gainer with levels going-up by 3.25 mt.
S Janakarajan, president of South Asia Consortium of Inter-Disciplinary Water Studies (SaciWATERs), says groundwater position was never comfortable in the city. “It is not the failure of the monsoon, it is we who failed to take measures to recharge our groundwater. Close to 80 per cent of rainwater runs off the surface, without reaching the water table.”
“Until and unless we store rainwater in water bodies and allow it to percolate into the ground, water tables will not get recharged. All our water bodies are shallow, encroached and they become dry within a month after the monsoon. We are heading towards complete desertification of the groundwater,” he said.