Water Harvesting for Wadi Al-Qasab, in Nineveh Governorate by Constructing a Virtual Dam
Abstract
Wadi Al-Qasab basin is considered one of the seasonal largest basins located in the eastern part of Nineveh Governorate. However, the region suffers from water scarcity in summer and abundance in winter. This study aims to determine the storage capacity resulting from the construction of a hypothetical dam at the bottom of the basin after analyzing the morphological and hydrological characteristics of the basin during 2018 using a GIS program. The Watershed Modeling System WMS program is used to calculate the curve number CN and annual surface runoff by introducing data for three parameters (soil moisture, ground cover, and hydrogeological characteristics). The surface runoff volume is estimated using a GIS program based on the runoff depth and basin surface area. Based on these findings, there are several possible scenarios for constructing a hypothetical dam at the bottom of the basin. The first proposed dam, with a length of 60 m, can hold water for 183 500 m3, whereas the second proposed dam, with a length of 285 m, will hold water for 144 2258 m3. In the last one, a dam spanning 530 m can store 5492700 m3 of water. After studying the morphological characteristics of the basin, it is found that it has a high CN, giving preference of water storage over infiltration. The largest third proposed dam can be chosen due to its high storage capacity, which gives the longest storage period for rainwater.
