GIS-Based Assessment of Wastewater Pollution in Afghanistan's Major Cities

Abstract

Water pollution caused by untreated industrial and domestic wastewater is an escalating environmental and public health crisis in Afghanistan. This study employs Geographic Information System (GIS) techniques to evaluate the spatial distribution of major water contaminants in key river basins, including the Kabul and Helmand Rivers. These contaminants include heavy metals (lead, cadmium, mercury, and chromium), biological pollutants (such as Escherichia coli, biochemical oxygen demand, and chemical oxygen demand), and physicochemical parameters (pH, total dissolved solids, and turbidity).The assessment is based on 25 water samples collected from five zones representing urban, industrial, and agricultural areas. Water samples collected from urban, industrial, and agricultural zones were analyzed using standard laboratory procedures. The results indicate that contamination levels in industrial zones significantly exceed the safety thresholds established by the World Health Organization and the United States Environmental Protection Agency—for example, 0.01 milligrams per liter for lead and 0.003 milligrams per liter for cadmium—with particularly elevated concentrations of these two heavy metals. Biological pollutants and organic loads are also alarmingly high, primarily due to inadequate wastewater treatment infrastructure. GIS-based spatial interpolation techniques identified pollution hotspots near densely populated and industrial discharge areas. The study highlights the urgent need for policy reforms, real-time monitoring, and the adoption of advanced water treatment technologies. These findings underscore the critical role of GIS in identifying high-risk areas and supporting sustainable water resource management strategies in Afghanistan.