With the water crisis looming, there is concern over groundwater reserves, one of the most exploited resources in the city. Experts warn it could get worse.
K. Mohammed Najeeb, Regional Director, Central Ground Water Board (CGWB), Union Ministry of Water Resources, told The Hindu that the extent of overexploitation of groundwater in Bangalore was nearly 200 per cent.
A brochure published by the board in December 2008 said that groundwater in three taluks (covering the Bruhat Bangalore Mahanagara Palike limits) — Bangalore North, Bangalore South and Anekal — has been over-exploited. This was also notified under the Central Ground Water Authority Act during March 2006.
Explaining this, Mr. Najeeb said: “If 100 mm rainfall percolates into the ground, we are drawing 200 per cent above it. It is just like overdrawing from a current account. There is no choice in the time of scarcity; but we cannot afford to go on overdrawing without taking measures to recharge it.”
The CGWB had recommended artificial recharge through structures such as recharge trenches, percolation tanks, check damns, subsurface dykes, infiltration wells and point recharge structures based on “site specific scientific investigation”.
Overexploitation of groundwater can be checked by waste water recycling for gardening, industrial cooling, toilet flushing and other secondary purposes, he added.