Analisis Debit Limpasan Permukaan dan Pemetaan Tingkat Kerawanan Banjir Berbasis Sistem Informasi Geografis di Kecamatan Landasan Ulin Kota Banjarbaru Kalimantan Selatan

Abstract

− South Kalimantan is in the yellow signal for Flood Disaster Emergency Alert status. All regencies/cities were hit by floods that not only inundated people's houses, but also hit and destroyed road and bridge infrastructure, cutting off access to public traffic. On January 12 – January 14, 2021, extreme weather occurred, namely heavy rain accompanied by lightning/lightning and strong winds which resulted in flooding in most areas of Banjarmasin, Banjarbaru, Banjar Regency, Tapin, Hulu Sungai Selatan, Hulu Sungai Utara, Balangan, and Tabalong. The purpose of this study is to analyze surface runoff and map the level of flood susceptibility in the Landasan Ulin Subdistrict, Banjarbaru City, South Kalimantan using DEMNAS and SPOT 6 image data in Banjarbaru City. The runoff discharge using the rational method and obtained a value of 229,568.57 m 3 day -1 with a catchment area of 3,251,946.40 m 2 . Then the flood susceptibility map has a value of 1.9 – 2.3 with a flood safe classification of 78,067.49 m 2 , 2.3 – 2.7 with a non-flood prone classification of 900,029.45 m 2 , 2.7 – 3.1 with a flood-prone classification of 1,459,619.99 m 2 , and 3.1 – 3.5 with a very flood-prone classification of 817,421.39 m 2 .