Using Statistics in Hydrology for Analyzing the Discharge of Yom River

The purpose of this study is to investigate the using statistics in hydrology for analysis the peak flow rate and analysis unit hydrograph on Yom river basin. Peak flow and unit hydrograph use analysis and design decision for flood control, hydraulic structures and retention pond. The statistics methods are Normal distribution, Lognormal distribution and Extreme value distribution had compared with monthly runoff data from six stations in Yom river. However, the result that is the most fitting by Extreme value distribution equation and used suitably analyze. The unit hydrograph using data that peak flow at return period 5, 10, 25, 50 and 100 years analysis flow rate and descriptive different depends on shape: catchment area, river and rainfall intensity.