Chennai Groundwater Sees Marginal Dip, Raising Sustainability Concerns
The groundwater table in 15 areas of Chennai has recorded a marginal decline in January compared to the same period last year, raising concerns about long-term water sustainability. Data from Metrowater shows that Madhavaram witnessed the steepest fall of 1.37 metres, followed by Kodambakkam at 1.1 metres. Ambattur and Teynampet recorded dips of 0.88 metres each, while Tiruvottiyur and Royapuram saw minor reductions of 0.22 metres and 0.29 metres, respectively. The average dip across the affected regions stood at 0.68 metres. However, when compared to January 2024, this year’s drop was only 0.3 metres, suggesting a relatively stable trend. Officials have assured that the decline will not significantly impact groundwater availability for residents dependent on borewells.
Growing Urbanisation and Shifting Demand for Water Resources
Despite the slight decrease, Chennai’s piped water supply remains robust, with Metrowater currently supplying 1,095 million litres per day (MLD), marking an increase of 51 MLD from the previous year. The city’s six reservoirs, including Veeranam lake in Cuddalore, hold a comfortable 11,374 million cubic feet (mcft) of water. This stable supply has allowed authorities to cut down water procurement from the Nemmeli desalination plant, reducing extraction from 80 MLD last year to 37.05 MLD now. However, the Minjur desalination plant remains inoperative due to contractor-related issues, and authorities are in the process of issuing a fresh tender to resume operations. Meanwhile, the 150 MLD desalination plant continues to supply 105 MLD, catering primarily to South Chennai’s expanding urban settlements.
Civic and Infrastructure Perspective: Impact on Water Security
While the decline in groundwater levels appears minimal, it underlines the larger issue of groundwater depletion in Chennai, particularly in urban pockets witnessing rapid construction. Borewell operators have reported a steep drop in requests for new installations, except from newly constructed homes, indicating that reliance on alternative sources, such as piped water and tankers, is rising. Experts warn that over-extraction and unchecked urban development could worsen groundwater depletion over time, necessitating stricter conservation measures. Additionally, with the Minjur desalination plant inactive, the city remains reliant on reservoir storage and desalinated water from Nemmeli, making it vulnerable to future fluctuations in rainfall and reservoir levels.
Sustainability Perspective: Need for Long-Term Water Management
The marginal dip in groundwater, while not immediately alarming, serves as a reminder of the need for sustainable water management. Chennai has seen unpredictable monsoons in recent years, making groundwater a crucial buffer against periods of low rainfall. Experts advocate for the expansion of rainwater harvesting initiatives, stricter regulations on groundwater extraction, and investments in alternative water sources such as treated wastewater for non-potable uses. Strengthening Chennai’s water security requires a multi-pronged approach, balancing infrastructure development with ecological conservation to ensure long-term resilience against climate change-induced water crises.
