Estimation and Analysis the mean flood dischargeusing the method of Regional flood Analysis inthe area Kheirroud in nowshahr up tosardabrud in chalous

In this research to control the floods in drainage basins (in the area kheirroud ofNowshahr to Sardabrud of Chalous), the mean of flood discharge with different returnperiods were estimated and analyzed using regional analysis method. To estimate andanalyze the floods, at first the basic raw data of annual peak discharge for the gaugingstations in the region were collected, then missing data was filled and new statistics,generated. The 29-year periods for this case were selected. Then, point analysis wasdone by the use of different statistical distributions. After they were studied, LogPearson Type III distribution was selected as the region. Then, Homogenity Test wasdone by the use of Run Test method. Moreover, the area of drainage basins wasmeasured. After measuring the level of significance (in level of 0.05) between area ofdrainage basins and mean flood discharge, it’s linear equation was obtained and on thebasis of it, mean flood discharge with the different return periods in ungauged drainagebasins was estimated.The results of estimation and studies have shown that, chalous watershed(drainage basin) has the most meant flood discharge value among the six watersheds.Other watersheds are as follows: sardabrud, kheirroud, kurkursar, and mashalak,Kheirsar-neirang (gerdekal rud or shalerud).