MANIPULATION OF FLOOD CONTROL CHANNEL PROFILE IN THE KEK LIKUPANG, PANTAI PULISAN, INDONESIA

Abstract

Flood, erosion, and sedimentation have become classic problems in the river. The two main parameters that significantly affect the phenomenon of flood are flow and sediment. Flood and sediment transport cause aggradation and degradation of the river bed, bring the bad influence to the construction in the river and environment. Therefore, it becomes important to conduct the manipulation of flood control channel profile in the selected area of Special Economic Area (KEK) that is Likupang, Pantai Pulisan. This research intends to obtain the design of channel shape and dimension for controlling the disasters that are influenced by the factors of environment, water resources, and climate change. One of the urgent factors in this research is to produce a design/recommendation for minimizing the negative impact that is triggered by floods and sediment transport, so it causes the disaster of geology and ecology. To reach the research aim, we carried out the survey of the existing conditions for determining the suitability of the analysis that will be used. The dimension of rainfall and watershed characteristics becomes the input in the HEC-HMS software for obtaining the design flood. Additionally, there is carried out the measurement/mapping of the river geometry. This is used in the application of HEC-RAS that will simulate the real-time flow condition in the field. Based on the analysis results of the flood control channel profile manipulation, there is obtained the dimension of multi-stage trapezoid channel with an upper width (La) of 10 m, lower width (Lb) of 1 m, and depth (h) of 3 m that can flow the design flood in amount of 36.5 m3/s (Q25). This information is a recommendation/reference in determining the management method of the environment and water resources in the Special Economy Area (EK) in the Likupang tourism-Pantai Pulisan as a super-priority tourism destination in making effort of disaster mitigation that is influenced by the factors of environment, water resources, and climate change.