QUETTA, Dec 9: The level of groundwater in the provincial capital is fast dropping because of over-exploitation and in the next 15 to 20 years there will be a serious shortage of the commodity, according to a geoscientist.

“Many studies have revealed that the groundwater level is dropping alarmingly and the Quetta aquifer may be exhausted within next 15 to 20 years because the groundwater recharge has not kept pace with the discharge from it,” Razzaq Khan Khilji, told Dawn.

He said the Quetta valley received approximately 185mm precipitation every year, of which a very small amount was recharged. Because of non-existence of a proper conservation strategy a huge amount of rainwater was lost in the shape of runoff or outflow from the Quetta sub-basin.

Mr Khilji, who is also the chairman of Balochistan Geoscientists Association, said the rates of pumping exceeded the rate of natural recharge and scanty annual rainfall and over-suction of water from more than 2,000 wells for domestic use and for irrigation purpose had resulted in steady decline in the groundwater level.

Poor governance and lack of interests and commitment by the government and public sector was aggravating the problem, he said.

He said that one option which was cheap and practiced since centuries to resolve this problem, was the use of low groynes (from boulders or gabions) across a water course, that reduced velocity, but increased depth and charge slightly, and thus improved percolation while keeping the self-cleaning transport capacity.

He recommended that besides delay action dams, other recharge facilities (spreading structures) might be applied which included recharge wells, recharge ponds, ditches, trenches and furrows especially prepared with a filter bed depending on the quality of water from source, the hydro geological boundary condition and the amount of water to be recharged.

He said that a comprehensive ground water enrichment programme in the entire Quetta valley which effectively improved the level of groundwater recharge, might be applied.

He was of the view that absence of qualified professional geoscientists in the water resources management system had led to this alarming situation and in order to avoid any future crisis, the government must include geoscientists in the water management system of the province.