Morphologic and Engineering Characteristics of Watersheds (A Case Study: East Wasit Watersheds that Feed the Al-Shewicha Trough - Iraq)

Abstract

Abstract The Al-Shewicha Trough represents a real flood hazard to Kut City (capital of Wasit Province, Iraq) as well as to the other cities along the Tigris River downstream Kut Barrage, especially heavy monsoon years. Under the acute lack of water resources around the world, many modern techniques in unconventional innovative water resources management were developed. In this study, ArcGIS was used in the morphologic analysis of six river basins which represent the main sources of feed for the Al-Shewicha Trough. The results show that the high value of the greatest length of a basin 1,5 and 6 indicate that these watersheds have high value of concentration time (tc) which delays the peak flow. All basins consisted of very coarse and permeable subsurface strata, and were of coarse texture. Circularity ratio Form factor and elongation ratio shows an elongated shape of all basins with lower peak flow and long duration. Analyses of soil data demonstrate that the soil type that covers a large area is loam soil within the hydrologic soil group type B, which indicates that all basins have low permeability and high runoff. The most predominant land use was bare soil and all basins have a covering of poor vegetation which highlights the basins that are most susceptible to erosion, thus resulting in the generation of higher sedimentation.