Evaluating Geomorphological Hazards of Urban Development in District 15 of Tehran for Hazard Management

Abstract

This study aimed to determine the geomorphological hazards caused by the urban development of District 15 of Tehran and to provide solutions to reduce risks in the region. In this study, Data required were obtained using 1:25000 topographic maps, satellite photos, and aerial images. Sample excavation points were surveyed by using GPS, and elevation map differences of the years 1965 and 2020 were provided via ArcGIS spatial analyst. The hydrology tool in the GIS was used to extract waterways to analyze waterway network changes. A geomorphological hazard map of the region was extracted by considering the criteria of distance from excavation points, distance from points where elevation decreases, distance from natural waterways, slope, and land use using AHP and Fuzzy models. Results indicated that hazards from excavation, floods, waterway network changes, and foot slope changes threaten society and human activities. Excavation and embankment caused by construction and road construction activities changed the local elevation of the zone in the region, consequently causing changes to the local slope and natural morphology. Foot slope and elevation changes were found to disrupt the compatibility of the regional morphology with the natural topographic state to cause floods in this region. The most notorious hazards in this region can be urban floods, which may affect various areas.