Analisis dan Upaya Pengendalian Banjir pada Sungai Aek Sirahar di Kecamatan Barus

Abstract

Based on data from the National Disaster Management Agency (BNPB) in 2022, the number of natural disasters in the flood category was recorded at 1,531. High rainfall every year causes flooding where the river basin cannot accommodate the amount of incoming water, especially in the Aek Sirahar River Basin in Barus District. This research analyzes the capacity of the Aek Sirahar river to respond to high rainfall every year. In this analysis, flood discharge is calculated using the Nakayasu Synthetic Unit Hydrograph Method and also the SCS Synthetic Unit Hydrograph with return periods of 2, 5, 10, 25, 50, 100 years. The regional rainfall calculation using the Thieesen Polygon Method is used. Based on the results of the analysis, it was found that the Aek Sirahar watershed river could not accommodate this high rainfall, resulting in water overflowing from the existing river boundaries.