POLA DISTRIBUSI HUJAN DAN PENGARUHNYA TERHADAP PENYIMPANGAN HIDROGRAF BANJIR DAS JANGKOK

Determining the rain pattern distribution is believed to affect design flood. Providing hourly rainfall observations can be obtained, and patterns determined. However, in areas that do not have one, flood discharge calculations are carried out by distributing daily using empirical methods. This study distributes into Jangkok watershed ABM Mononobe methods calculates hydrograph Nakayasu model. The synthetic unit obtained from actual then compared with generated distribution, deviation measured. results showed gave same shape as observation only for 2 hours of duration. As long lasts 3-6 hours, peak (Qp) tends lower, 7-20% 2-7% ABM. Then Qp becomes overestimated (5-12%) a duration >6 hours. gives time (Tp) 1-5 1 hour earlier In contrast, produces times longer than hydrographs rain. Generally, two provide more significant