Determining the Surface Drainage Network Causing Flash Floods in Central Erbil Sub-Basins in Northern Iraq Using GIS and Geospatial Technique

Abstract

This research aimed to identify the most important geomorphological and morphometric properties of the Central Erbil sub-basin and the possibility of benefiting from its water by using it optimally for various uses. The study used the descriptive analytical approach to extract and analyze the morphological and hydrological properties of the valleys in the research area to determine the properties of water drainage networks and variables influencing surface earth formation. Watersheds' morphometric parameters are computed and Identified using Remote Sensing and Geographic Information Systems. Central Erbil sub-basin has radial, parallel, and dendritic drainage patterns and spans 2107 km2. Central Erbil sub-basin is divided into six sub-basins. The present study focused on linear and areal morphometric aspects of sub-basins. The study focuses on morphometric characteristics, for example, drainage density, stream order, stream texture ratio, length, bifurcation ratio, frequency, circularity ratio, form factor ratio, and elongation ratio, which have changed over time. Morphometric studies of the Central Erbil sub-basin indicate that it is a sixth-order drainage basin. This means that the basin is highly permeable and has dense vegetation. Aspects of the basin's morphometric study revealed that it has a significant potential for flooding, suggesting that runoff from the watersheds' upland areas has strongly permeated the basin's gentler downstream portion and increased the capacity for groundwater.