بررسی واقعه سیلاب شهری در جنوب شرق شهر مشهد

This survey was conducted with the aim of studying the flood event that occurred on May 26, 2024 in the southeast area of Mashhad city. In this rainfall event, about 42 mm of rain was rained in a period of about 70 minutes. In the last quarter of the rainfall, the precipitation was mainly in the form of hail. At the outlet of the studied basin and at the entrance to the flood transfer channel, based on the field visit, the peak flood discharge was estimated to be about 14 cubic meters per second. At this point, the maximum capacity of the urban channel to transfer the flood is 9 cubic meters per second. Unfortunately, a part of the canal's capacity was taken by the sedimentation, and the flood with a flow of more than 10 cubic meters per second entered the park after passing through the downstream boulevard and spread over the park and the adjacent boulevard. This investigation showed that several factors played a role in the flood entering the city and the loss of life and financial losses. High rainfall intensity, continuous rainfall, lack of attention to upstream watershed management and many problems in urban flood control are among the most important factors. This survey showed that the outlet of the upstream basin of this area has several tens of thousands of cubic meters of runoff annually, which unfortunately, after reaching the outlet of the basin, this God-given blessing turns into large floods.