Pemetaan Banjir Menggunakan HEC–RAS pada Kebun Pisang PT Agro Prima Sejahtera di Sekampung Udik, Lampung Timur

Abstract

Floods can occur in the form of inundation such as agricultural land, settlements, and the city centre. The purpose of this research was to map the spread of flood areas in banana plantation of PT Agro Prima Sejahtera in DAS Way Sekampung using the ArcGIS application and HEC-RAS. The benefits of the research was to provide information for the local government, on the flood-prone areas as material considerations for drafting plans for the management of the watershed. The hydrograph discharge was obtained from the results of the simulation of the SWAT application. The peak discharge of 97.90 m 3 /s was occurred on 6 October 2007, minimum discharge of 19.25 m 3 /s was occurred on 14 November 2007, and the mean average discharge was 41.14 m 3 /s. Cross section of trapezoid-shaped channels had an area of 178.52 m 2 , the elevation was 0.5 m/segmen, the width of the tunnel base was 9.1 m, and water level in the channel was 6.23 m. The height of the channel was 5 m, and the flood occurred on the channel when the maximum condition was 2.17 m. Manning coefficients used on meandering, sloping, and grassy ground channel type was 0.025. The total flooding area when the maximum discharge was 32.48 m 2 and on the minimum condition was 0.001 m 2 which was occurred in the upper river.