The impact of Kahramanmaraş urban development on the geomorphological units and natural disasters

Changes on geomorphological units emerged by Kahramanmaraş urban development and these changes' relevance to natural disasters were scrutinized in this study. The city of Kahramanmarai was located on a low plateau between the Maraş Plain and the Mount Ahır. The city later expanded towards the Maraş Plain. In recent years, the city has developed rapidly in the east-west direction in the south of Mount Ahır and occupied the plateau, valley and alluvial fans in this area. In this process, changes have been experienced in geomorphological units and an increase has been observed in disasters such as floods and overflows. Since the first settlement of Kahramanmaraş corresponded to the hilly area on the plateau, it was a disaster-free area. However, the area where the city developed in the recent period was split by the streams descending from Mount Ahır. The occupation of the river beds by the settlements has led to an increase in disasters such as flood and overflow. Apart from these disasters, the fact that the city is located in the Maraş Triple Junction indicates that the risk of earthquakes is very high. The great earthquakes happened in the past reveal how important this disaster is for the city. The city of Kahramanmaraş is a settlement where the population is constantly increasing due to favorable climatic conditions, fertile soil structure and geographical location, which puts pressure on the natural environment. With the rapid urbanization, the expansion of the city on the fault zone and plain creates a high disaster risk. In addition to this risk, the natural balance on the slopes and ridges is disrupted by excavation works in the construction of buildings and roads. Excavations from the construction works are filled into stream beds and valleys. With the rapid and unplanned urban development, natural processes in the geomorphological units in the areas where the city is located are being intervened. As a result of all these processes, urban development causes changes in geomorphological units. This change in geomorphological units increases the risk of disasters. Satellite images and numerical data were used to determine the impact of urban development on geomorphological units and natural disasters in Kahramanmaraş. According to the analyzes carried out, it was determined that the urban area is expanding rapidly in parallel with the increase in the population in the city of Kahramanmaraş. Human interventions on the valleys cause the city to become risky in terms of floods and overflows. Interventions on the slopes will be able to trigger landslide incidents during earthquakes. High-rise buildings in the urban area will be able to cause higher losses in possible earthquakes. According to these results, in the development of the city, the necessary measures and the plannings should be carried out by taking into account the existing disasters.