Overexploitation plunges groundwater levels in just 4 months in Bengaluru

Groundwater levels in Bengaluru dropped significantly in four months as the water crisis forced people and authorities to drill new and deeper borewells, new data obtained by DH shows.

The Bengaluru South taluk is the worst affected, where water levels dropped by nearly 15 metres between December 2023 and April 2024. Other taluks recorded a drop of two to six metres in groundwater levels.

While groundwater levels usually go down during the summer, the water crisis this year was predominantly due to the failure of borewells. Authorities had hoped that levels would not go further down.

"It became a vicious cycle where the crisis was due to the failure of borewells, and to wade through it, many citizens drilled borewells deeper, and thus, the groundwater levels went further down," a senior official from the Karnataka Groundwater Authority (KGWA) lamented.

While the Bangalore Water Supply and Sewerage Board (BWSSB) tried to regulate the use of borewells by mandating pre-approval, illegal borewells continued to be drilled, impacting groundwater levels directly.

"Every day, you can see at least five illegal borewells being drilled. While the BWSSB has been able to stop some, others continue unabated," said Abhay Kumar, a resident of Mahadevapura.

Acknowledging that the groundwater levels were going down significantly, the BWSSB said it was taking measures such as filling up lakes and constructing new recharge pits to improve groundwater percolation during the monsoon.

"We understand that there has been an over-exploitation of groundwater and are trying our best to regulate it. From filling lakes with treated water to constructing recharge pits, we are taking up many activities to improve the groundwater levels. We are also creating awareness among citizens to implement rainwater harvesting systems and divert excess water to recharge pits," said BWSSB Chairman Dr. Ramprasat Manohar V.

Officials from the KGWA believe that the lack of rains in March and April may have worsened the problem but are hopeful that a good monsoon will help improve groundwater levels significantly.