University of Tehran Journal of Range and Watershed Managment 5044-2008 76 1 2023 06 21 Increasing the accuracy of river network auto-extraction using Parflow and Priorityflow packages Increasing the accuracy of river network auto-extraction using Parflow and Priorityflow packages 61 75 92893 10.22059/jrwm.2023.354127.1691 FA Sadegh Dalfardi Department of Reclamation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran Ali Salajegheh Department of Reclamation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran Alireza Moghaddam Nia Department of Reclamation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran Mohammad Danesh Yazdi Department of Civil Engineering, Sharif University of Technology, Tehran, Iran Hossein Hashemi Division of water resources engineering, Lund University, Lund, Sweden Journal Article 2022 12 14 Accurate slope map and the governing river network of a river basin are key inputs of hydrologic models. The purpose of this study was to investigate the effectiveness of the PriorityFlow tool in topographic data processing with the aim of improving slope map extraction in the eastern Faryab Basin. PriorityFlow is a tool in the R programming environment, which aims to generate the correct slope map and to form a network of continuous pathways that matches the observed river network. To process the digital elevation model and prepare the slope map, three input files were used, including the digital elevation model, the representative map of the watershed and the representative map of the observed river network of the study area. After producing the slope map using this package, the obtained results were compared with the outputs obtained from other traditional tools available in the Parflow hydrological model. Specifically, the river network map related to the two slope maps were extracted by the Parflow model under the condition of very low permeability of the domain surface and compared with the observed river network of the study basin. The results showed that the slope map produced by the PriorityFlow tool has led to the production of a more accurate river network that matches the real river network of the eastern Faryab basin. Also, this software package is able to produce the slope map with enhanced accuracy and based on non-diagonal connections along the cell levels in the digital elevation model of the study area. Accurate slope map and the governing river network of a river basin are key inputs of hydrologic models. The purpose of this study was to investigate the effectiveness of the PriorityFlow tool in topographic data processing with the aim of improving slope map extraction in the eastern Faryab Basin. PriorityFlow is a tool in the R programming environment, which aims to generate the correct slope map and to form a network of continuous pathways that matches the observed river network. To process the digital elevation model and prepare the slope map, three input files were used, including the digital elevation model, the representative map of the watershed and the representative map of the observed river network of the study area. After producing the slope map using this package, the obtained results were compared with the outputs obtained from other traditional tools available in the Parflow hydrological model. Specifically, the river network map related to the two slope maps were extracted by the Parflow model under the condition of very low permeability of the domain surface and compared with the observed river network of the study basin. The results showed that the slope map produced by the PriorityFlow tool has led to the production of a more accurate river network that matches the real river network of the eastern Faryab basin. Also, this software package is able to produce the slope map with enhanced accuracy and based on non-diagonal connections along the cell levels in the digital elevation model of the study area. https://jrwm.ut.ac.ir/article_92893_c68af855ddfb2aa02dc88e2d58b0a51e.pdf