KABUL (SW) – A latest study has indicated that over the past two decades, groundwater — as the primary water supply source for Kabul residents — has been exploited extensively, causing large drawdowns.
According to the study by the Afghanistan Research and Evaluation Unit, the imbalance between groundwater recharge and groundwater use is considered to be a key driver for the extreme decline in groundwater.
It said Kabul is a fast-growing city with urban area expansion rate of 13.7 percent between 1999 and 2008. The expansion in urban areas are directly affecting groundwater recharge from precipitation, because the areas exposed to infiltration are converted permanently to housing areas. The urban area expansion is associated with increases in paved areas of roads, streets and walkways.
More importantly, urbanisation is associated with protection of riverbanks, streambanks and drainages from erosion, which otherwise serve as natural infiltration basins. The heavily protected urban drainages convey the collected surface runoff water much faster into the Kabul River, where, after a short residence, it will leave the basin; similarly, in the areas where the drainages have poor connectivity, the accumulated water on the surface is easily evaporated without contributing to groundwater regeneration.
The study results suggest, groundwater sustainability in Kabul region basins faces many challenges but there are also opportunities. If central Kabul sub-basin is viewed as integral part of its four neighbouring sub-basins, it becomes clear that area’s with groundwater availability is not located farther away from largest extraction areas. A long-distance water supply from neighbouring Panjsher, Shamali and Logar sub-basins can bridge the gap between groundwater availability and use and therefore, can strongly reduce the stress on groundwater in central Kabul sub-basin.
The direct precipitation on the land surface may have marginal contribution to the groundwater regeneration, but the drainages collecting the water from urban area’s catchment can contribute. The paved areas either fully abstract water infiltration or strongly reduce the infiltration rates. The outcome of a complete sealing of surfaces by paving is already affecting the Kabul inhabitants in the form of flooding even during a very moderate precipitation for a few hours.
The (AREU) organized a virtual event on 18 May 2020 to discuss the findings and policy recommendations of its recent research issues paper, “Surface Groundwater Interaction in the Kabul Region Basin”. This paper was authored by Dr Najibullah Sadid, and generously funded by the European Union (EU). It is part of the EU’s three-pronged research effort into essential areas of Natural Resources Management (NRM).
Dr Sadid, the main author of the paper, presented a summary of his study, explained all aspects of the research and its limits and answered several questions raised by the participants who were senior technical government officials in the water sector, academic experts and some general viewers.