Measuring the Use of Detention Basin as Flood Control System at Campus i Lambung Mangkurat University Banjarmasin, Indonesia

Abstract

South Kalimantan Province has experienced floods during the rainy seasons due to high intensity of precipitation. In mid-January 2021, flood inundated the Banjarmasin Campus I area of Lambung Mangkurat University (ULM Campus I). In mid-December 2021, other flood case inundated Campus I ULM. The research aims to measure the effectiveness of using detention basin as flood control in Banjarmasin campus area of ULM. Data collection is based on hydrological analysis of rain data to obtain a designed flood discharge with a return period of 20 years using the Der Weduwen method. The hydraulic analysis of the transverse and longitudinal sections on the river section of Campus I ULM was analyzed using the HEC-RAS. Based on the value of the flood volume, an analysis of the volume of the detention basin is carried out, where the volume of the detention basin must be greater than the volume of the flood. Spatial data is used to obtain contours using ArcGIS, to determine the optimal location of the detention basin. Based on the simulation, cumulative planned flood volume was 36,010 m3 with a discharge value of 89.30 m3/s. It was designed two detention basin. First detention basin dimension is 160 m x 130 m x 1.5 m located closed to General Building. The second one, located at Master of Law Building with dimension is 120 m x 35 m x 1.5 m First detention basin dimension is 160 m x 130 m x 1.5 m located closed to General Building. The second one, located at Master of Law Building with dimension is 120 m x 35 m x 1.5 m.