THE ANALYSIS OF ALTERNATIVE FLOOD CONTROL AND FLOOD RISK REDUCTION IN PALU CITY, CASE STUDY : PALU RIVER

• Main Author: Putra Islamiyanto, Yudho
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/70358
• Institution: Institut Teknologi Bandung

Palu River is a river in the Palu watershed whose potential problems are very large. during high-intensity rains often result in a large amount of material from upstream to downstream, resulting in siltation. Palu River is an area with a fairly high level of flood risk as every year there are often floods that have a fairly detrimental impact on Palu City. In this study, an analysis related to flood overflow was carried out with 1D and 2D modeling with HEC-RAS version 6.0.1, and based on the overflow model, it became the basis for the effectiveness of the planned flood control scenario. Based on the results of hydrological analysis using HSS SCS CN, the Q25 flood discharge on the Palu River was 400.08 m3 /second. Hydraulic analysis and 2D flood modeling using HEC-RAS 6.0.1 in existing conditions without flood control efforts resulted in a flood area of 3.90 km2 with 28.60% low hazard class (D < 0.75m2 /s), 23.88% medium hazard class (D 0.75 >1.5 m2 /s), 47.51% high hazard class (D >1.5 m2 /s). Flood control efforts in the Normalization scenario resulted in a flood area of 1.61 km2 or provided a 58.50% reduction in flood area. Flood control efforts in the River Embankment scenario resulted in a flood area of 0.82 km2 or provided a reduction in flood area of 78.83%. Normalization and flood control efforts of the Embankment scenario resulted in a flood area of 0.33 km2 or provided a reduction in the area of the flood area by 91.37%. The level of flood risk in existing conditions almost entirely has a medium capacity level. Flood control efforts with a Normalization scenario reduce the risk level of flood disasters in Sunju and Tinggede from high to medium. Flood control efforts with the Embankment scenario reduce the risk level in Lere, Nunu, Tawanjuka, Tinggedem, Kalukubula, and South Birobuli villages from medium to low. Meanwhile, flood control efforts in the Normalization and Embankment scenario reduce the risk level of the entire village to low.