THE SEROK RIVER CATCHMENT FLOOD HYDROGRAPH

Global climate change is expected to cause an increase in the intensity and duration of extreme rainfall events that occur today. The leading flooding various world regions, including flat coastal areas such as Serok River catchment Kota Pontianak, influenced by tides, excessive rainfall. This article presents results analysis impact precipitation on peak discharge flood hydrographs catchment, Pontianak.Maximum daily data for 2009-2020 recorded at PTK-11 Pontianak Station were selected using Annual Maximum Series Method. Frequency was conducted best distribution method from Normal, Log Pearson Type III, Gumbel I obtain design transformed into next stage Snyder Synthetic Unit Hydrograph based several return periods.The show there are changes area each period. location land use value rain significantly affect calculation plan discharge; more significant higher intensity, greater resulting release. most considerable (Qmax) 2, 5, 10 years occurs STA 1 + 100, w.290 m3/s, 0.347 0.377 respectively. Thus, this causes periodic flooding/inundation conditions, especially have low elevations.