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.