FLOOD RISK ANALYSIS IN BATANG ANAI DISTRICT, PADANG PARIAMAN REGENCY, WEST SUMATERA

• Main Author: Fathi Yakan, Annisa
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/71730
• Institution: Institut Teknologi Bandung

Batang Anai District is one of the sub-districts in Padang Pariaman Regency. Batang Anai District is also a downstream area of the Batang Anai river. The Batang Anai River is one of the longest rivers in West Sumatra, which originates at the foot of Mount Singgalang and empties into Batang Anai District. The Batang Anai River has an important role, one of which is irrigation. As the estuary of the Batang Anai River, Batang Anai District is often hit by floods. Reporting from BPS data, in 2021 Batang Anai District was hit by floods 13 times. Floods that are quite frequent and occur almost every year will certainly disrupt community mobility. Meanwhile, based on Padang Pariaman Regency Spatial Plan 2010 - 2030 chapter V Determination of Strategic Areas, Batang Anai District is a priority area for the Regency, including the Katapiang Airport gate, the Central Business District trade area, the Hajj embarkation area, the main corridor area, and the industrial area. This study aims to map a flood risk map in the Batang Anai sub-district and provide alternatives in reducing the risk of flooding that occurs. The basis of this research is PERKA BNPB No. 2 of 2012 Concerning General Guidelines For Disaster Assessment. This study analyzed floods with a return period of 20 years (Q20) using HEC-RAS 6.2 with a combination of 1D and 2D modeling. In calculating flood hydrographs, this study uses HEC-HMS 4.8. Mapping hazard areas, vulnerabilities and risks using QGIS 3.26.2 and ArcMAP10.8. Based on the Q20 modeling results, the resulting flood inundation is 875.36 ha. Whereas after the addition of the embankment as an alternative to reduce the risk of flooding, the flood inundation decreased by 33.07% to 585.90 ha. In the Q20 flood modeling, Kasang and Katapiang sub-districts have a high flood risk index while Sungai Buluah, Sungai Buluah Selatan, Sungai Buluah Utara, Sungai Buluah Barat, Sungai Buluah Timur sub-districts have a moderate flood risk index. After the addition of the embankment there was a decrease in the flood risk score in the review area.