Impact of identical digital elevation model resolution and sources on morphometric parameters of Tena watershed, Ethiopia

Digital elevation models (DEMs) are the primary form of satellite data used to design and analyze the hydrology and hydraulic behavior of watersheds for water resource development. The primary objective of this study is to conduct morphometric parameter analysis using SRTM(30m), ASTER(30m), and ALOS(30m) data to determine the impact of identical DEM resolution and DEM sources on the Tena watershed by computing the basic and derived parameters. In this study I used data from two sources for morphometric parameter analysis with ArcGIS software. The results indicate that the DEM sources did not provide similar results for all parameters: ASTER(30m) was the maximum output for almost all parameters, followed by SRTM(30m) and ALOS(30m). The findings of this study suggest that ASTER(30m) is the most suitable data source for flood risk assessment, soil erosion, sediment, streamflow, and other watershed modelling, while ALOS(30m) is best suited for peak discharge analysis. All of the used DEM sources were suitable for computing watershed shape parameters. In general, the resolution of DEMs impacts the hydrological and hydraulic study of any watershed, with resulting effects on decision-making for watershed management and development.