Evaluating the process of physical development of residential areas towards flood prone areas (Case study: Sanandaj city)

Flood is one of the dangers that threaten many cities in Iran. One of the areas exposed to this risk is Sanandaj city. Due to its proximity to the Qeshlaq River and its hydrogeomorphological condition, Sanandaj has a high potential for flooding. Due to the importance of the issue, in this research, the development process of the residential areas of Sanandaj city towards flood-prone areas has been evaluated. In this research, a 30-meter height digital model, 1:100,000 geological map, Landsat satellite images, as well as various digital information layers have been used as research data. The most important tools used in this research were ENVI and ArcGIS software. This research has been carried out in two general stages, in the first stage, by using the integrated Fuzzy-AHP model, flood-prone areas were identified in the study area, and in the second stage, by using satellite images, the development process of the residential areas of Sanandaj city The direction of flood-prone areas has been evaluated. Based on the results, the eastern areas of the urban area of Sanandaj have a high potential in terms of flooding due to their proximity to the Qeshlaq River as well as the low elevation and slope. Also, the results of this research have shown that the size of the residential areas of Sanandaj city in 1990 was about 14.8 and in 2020 it was about 27.1 square kilometers. In 1990, about 2.6 square kilometers of the residential areas were exposed to flood risk but it has increased to 7.9 square kilometers per year. Based on this, it can be said that the flood situation of the region has not been given much attention in urban planning.