A novel approach of the application of drainage morphometry and analytical hierarchy process to the flood susceptibility assessment of the ungauged Kakum River basin, using remote sensing data

Ungauged river basins are among the most threatened water resources in this era of climate change and increasing population growth due to a lack of infrastructure for data collection and analysis for better management decisions. This paper explores the use of drainage morphometry and the Analytical Hierarchy Process (AHP) of the Multi-Criteria Decision Making (MCDM) to decipher the basin morphology and flood susceptibility of the ungauged Kakum River basin using remote sensing data. Fifteen (15) morphometric parameters were assessed for the linear, areal, and relief characteristics of the basin, while ten (10) factors were considered to identify and map the flood susceptibility of the basin spatially. The morphometric analysis indicates that the Kakum River basin is elongated with a flat terrain and characterized by reduced peak flows (Rb = 1.26; Rr = 0.025; Rc = 0.215). A flood susceptibility map generated by assigning relative importance to elevation (0.28), slope (0.19), drainage density (0.12), and distance to rivers (0.12), shows five classes of flood potential ranging from very low (0.063%), low (23.69%), moderate (56.85%), high (19.33%) to very high (0.059%). The results from this study demonstrate the effectiveness of remote sensing data in understanding the morphology and assessing the flood risk in data-scarce regions like Ghana, thereby providing valuable insights for flood management.