Future perspective of water budget in the event of three scenarios in Afghanistan using the WEAP program

Abstract

In this study, WEAP (Water Evaluation and Planning System) software was used for the water resources management and water budget calculation of the Balkh River Basin, the sub-basin of the Northern River Basin in Afghanistan. The water resources in the basin and 10 demand sites (irrigation, drinking water, etc.) were introduced to the software, and precipitation, evaporation, runoff, etc., were obtained from stream gauging stations for long years (2010–2021). Hydrological data and information on population, irrigation lands, and drinking water use were entered. Scenario-1 (current situation) was created by entering the existing data in the created model. Subsequently, the long-term monthly average maximum and minimum values of precipitation, evaporation, runoff, and similar values were added to the current scenario. Forecast results between the years (2022–2050) were created with Scenario-2 (optimistic case) and Scenario-3 (pessimistic case), and analyzes were carried out in three different situations, and the results were examined. According to the analyzes, the current water potential found by the inclusion of surface water and groundwater from the Mezar-i-Sharif Region in the Balkh River Basin is 4747 million m3 annually; it has been determined that this value will be approximately 9741 million m3 in 2050 in the optimistic scenario and 1811 million m3 in the pessimistic scenario. It has been determined that the water need, which cannot be met as 29,394 million m3 in the current situation, approximately 14103 m3 in the optimistic scenario, and 49,979 million m3 in the pessimistic scenario in 2050. While the current met need of the Balkh River Basin is 7.81 % with losses, it has been calculated as 27.14 % in an optimistic situation and 1.71 % in a pessimistic situation for 2050. While the current met needs of the Basin, excluding losses, is 12 %, it is calculated as 33.9 % in the optimistic situation and 3.1 % in the pessimistic situation for 2050. It is understood that Afghanistan's water resources should be handled with an integrated water resources management (IWRM) approach, and future water resource planning should be made by considering human needs, environmental impact, and government visions. Water resources should be planned most efficiently by controlling the amount of undocumented wells, drilling, and detecting the losses and leakages in the existing systems with certain methods.