Where Floods Strike: Flood Hazard Risk Mapping in Tanjay City
Keywords:
Flood Hazard Index, Flood Risk Assessment, Tanjay City, Topography, Quantitative AnalysisAbstract
This research evaluates the risk of flood hazard in Tanjay City, Negros Oriental, by creating and using a Flood Hazard Index (HFI) that is specifically tailored to the 24 barangays of the city. Flooding is a perennial environmental concern in Tanjay City, which is caused by a combination of low-lying areas, proximity to river systems, and differences in topographic features. In order to spatially quantify the susceptibility of the area to flood hazards, this research uses a quantitative method that takes into account elevation, average annual rainfall, slope, and distance to rivers as the primary factors that contribute to flooding. The variables used in this research were standardized using a scoring system that is adjusted to suit the terrain of Tanjay City, in order to prevent the overestimation of flood hazard risk in the upland barangays. The findings show that the barangays in low-lying areas and near the riverbanks, especially the Poblacion barangays and other low-lying areas, have a higher level of flood hazard. On the other hand, the barangays in mountainous and hinterland areas have a lower flood hazard susceptibility because of their elevation, slope, and distance from the riverbanks. The findings on flood hazard also show that flood hazard is not uniform in space. In general, the Flood Hazard Index is a systematic and practical tool for identifying priority areas for flood mitigation, land use planning, and disaster risk reduction. The results support evidence-based decision-making for local government units and highlight the importance of quantitative flood hazard modeling in improving community resilience and sustainable urban development in flood-prone cities.
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Copyright (c) 2026 Jannah T. Dael, Mae Theresse A. Borromeo, Zuleyka D. Gabuc (Author)
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