Analisis Curah Hujan untuk Pendugaan Debit Puncak dengan Metode Rasional pada DAS Percut Kabupaten Deli Serdang

Abstract

Rainfall is the most important input component in the hydrologic process. Rainfall characteristics, such as intensity (I), duration (t), depth (d) and frequency. Intensity that is related to duration and frequency can be expressed by Intensity-Duration-Frequency (IDF) curve. Data used in this research comprised of rainfall and land use data. The data of rainfall used were daily rainfall recorded in Saentis station. In the research, daily rainfall depth was calculated by frequency analysis, which was started by determining the daily maximum mean rainfall with partial series method, followed by calculating the statistical parameter to choose the best distribution. Intensity could be calculated by Mononobe method and to calculate flood discharge using the rational method. The result of this study indicated that the Log Pearson Type III distribution fit to most of data in the Percut DAS and flood discharge with return period can be calculated .