Water Resource Simulation in an Arid Watershed Considering an Allocation for Dust Stabilization and Different Scenarios of Water Supply and Demand

Document Type: Research Paper

Authors

1 Assistant Professor of Civil Engineering, University of Sistan and Baluchestan, Zahedan, Iran

2 Ph.D student of Civil Engineering, University of Sistan and Baluchestan, Zahedan, Iran

3 Associate Professor of Civil Engineering, University of Sistan and Baluchestan, Zahedan, Iran

Abstract

Water is the main demand of people settled in the arid areas of large watersheds.
This demand is more necessary and critical in the areas with the potential of dust
sources and fine sediments entering into the watershed in a long-time period. Sistan
watershed to the south-east of Iran is a region with the specific hydrological
conditions. The 120-day winds blow continuously in the summer propagating large
amounts of dusts directly into the cities and rural areas. In this study, a demand is
considered for the dust stabilization in the study area. A field surrounding the
watershed that directly affects the amount of dusts is selected. The amount of water
demand that is needed for the stabilization and saturation of the soil is measured by
the soil sampling and experimental on-site works. A demand for dust stabilization is
defined and the water resources systems are simulated. Different scenarios of water
supply and demand are considered. Results show the unmet demands of the different
scenarios (Sc) in a 15-year period in the region. The highest amount of unmet water
demand is calculated for the scenario No.10 that is the combined effects of reducing
agricultural land use and increasing the agricultural efficiency and reducing
evaporation from Chahnimeh reservoir and flow of discharge in accordance with the
agreement between Iran and Afghanistan enforced in 2015. Different scenarios are
evaluated in terms of dust stabilization priority and also agriculture using the analytic
hierarchy method. This shows the high score of Scenario No.9 that is the combined
effect of reducing agricultural land use and the increasing the agricultural efficiency
and reducing the evaporation from Chahnimeh.

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