Normalizing the river of Cisangkuy to reduce the flood risk in the future

Abstract

The rapid population growth has made residential land more widespread. causing the surface water runoff getting bigger and coupled with the narrowing of the river cross-section by sediment so that the river’s capacity is no longer able to accommodate the existing flood discharge. This study aims to reduce the risk of flooding in the Cisangkuy river. Modeling was carried out using HEC-RAS 2D. Modeling results in the existing conditions show that water has flowed into the residential area. Handling in the form of normalization of the Cisangkuy River as an appropriate alternative for reducing flood risk. After normalization, there was a decrease in the water level in the upper reaches of the Cisangkuy river from an altitude of 672.13 masl to 667.85 masl and in the middle of the Cisangkuy river it fell + 3.3 meters. which was originally from an altitude of 668.57 masl to 665.21 masl. The improvement of the Cisangkuy River has had a significant impact on the flow of the Cisangkuy tributary and the urban drainage system around the area. So that the Cisangkuy River can accommodate the discharge and the risk of urban flooding can be reduced. With this risk reduction, flooding that has an impact on the social, economic, and health sectors can be controlled and can be focused on future urban problems.