Development of flood forecasting model and warning systems at Way Ruhu – Ambon

Abstract

Way Ruhu has a river with the slope of the land is steep. The heavy rains that often occur in the city of Ambon resulted in floods and landslides in several places thus to give a big loss to the people in the city of Ambon both the loss of property and lives. This study was conducted with the aim to determine the magnitude and time of flooding in the Way Ruhu watershed, the modeling results will be applied in android so that people can evacuate early because information can be received more quickly and the Government can prepare better mitigation programs. Modeling methods are carried out using 2D software HEC-RAS 5.0.7 which requires hydrological and topographical data as the main inputs. The output from HEC-RAS is a flood map, flood height, and duration of the flood. The results of this study indicate that the time between the upstream river rise and the arrival of floodwater in the downstream is less than one hour, with flood characteristics as high as 1-5 meters and receding within 4 to 11 hours.

Spatial Modeling of Flood Prone Areas in Huamual Sub-district Seram Bagian Barat Regency Indonesia

“…Rainfall is one of the main factors that have a major influence on the occurrence of flooding in an area . The amount and intensity of rainfall can affect the volume and speed of water flow, drainage capacity, and groundwater storage (Marasabessy et al, 2020).…”

Analysis of the Effect of Land Use on Flood Discharge in the Pangkajene River Basin, Pangkajene Regency and the Islands

“…The development of the population and its activities, the progress of the economy of the people of Pangkep Regency and the influence of advances in technology and information as well as national and global changes encourage changes in the selection of settlement locations and activities, the development of activities and functions of a location and region will ultimately change the use of space (Marasabessy et al, 2020).…”

Pemetaan Daerah Rawan Banjir di Kota Ambon Menggunakan Sistim Informasi Geografis

“…Kota Ambon merupakan ibukota Provinsi Maluku yang memiliki siklus banjir tahunan yang disebabkan oleh intensitas hujan yang tinggi dan buruknya kondisi sungai, dan tidak diimbangi dengan penyerapan air yang baik sehingga air meluap menimbulkan bencana banjir (Hermawan et al, 2021). Badan Nasional Penanggulangan Bencana (BNPB, 2018), menjelaskan bahwa, Kota Ambon merupakan daerah yang memiliki indeks resiko bencana tertinggi di Provinsi Maluku, Kota Ambon merupakan daerah yang sering terjadi bencana banjir yang disebabkan dari pengaruh faktor hidrometeorologi dan kondisi fisik wilayah yang ada (Marasabessy et al, 2020). Berdasarkan Laporan Kajian Kerentanan dan Resiko Iklim Pulau Ambon dan Pulau Leasa (USAID, 2017), Kota Ambon memiliki potensi luasan banjir yang berada pada kelas sedang dan potensi penduduk yang terpapar berada pada kelas tinggi.…”