Abstract. From 2003 to 2022, Mashhad’s upstream region saw rapid urban growth, replacing grasslands and bare land with impervious surfaces. This shift significantly altered hydrological responses, increasing flash flood risk near Golestan Dam. Precipitation trends during the same period showed no major changes in rainfall intensity or totals, confirming that land use change, not climate, is the primary driver of flood hazards. These results highlight the urgent need for sustainable land management and community engagement to safeguard dam safety in urbanizing wadi systems.

Keywords