Flood Risk Reduction Using Integrated Community-Based Disaster Risk Management and Geo-Spatial Approaches in Gin River Basin, Sri Lanka

Abstract

Floods present considerable risks to the sustenance of livelihoods, infrastructure, and social fairness within the Gin River Basin, Sri Lanka, necessitating an integrated methodology for efficient risk mitigation. This article investigates the implementation of Community-Based Disaster Risk Management (CBDRM) combined with geospatial techniques to reinforce community resilience and involvement in reducing flood hazards. Encompassing an area of 932 square kilometers, the research site displays various climatic conditions impacted by monsoons and diverse topography spanning from mountainous forested inclines to agricultural floodplains. The methodology involved the selection of 100 households and stakeholders for data collection through quantitative surveys and qualitative interviews, focusing on demographic characteristics, livelihood trends, flood impacts, and coping strategies. Data was acquired from both primary and secondary resources, encompassing governmental publications and hydrological observation stations. The Delphi method was employed to enhance the CBDRM model customized for the area. The investigation pinpointed crucial socio-economic variables influencing community engagement in flood risk governance. The outcomes of the study underscored the recurrent flood occurrences intensified by climate variations, underscoring the necessity for a multifaceted strategy encompassing both physical and non-physical interventions. The strategy for lessening flood risks integrates traditional local knowledge, participatory risk evaluations, and sophisticated geospatial technologies like OpenStreetMap for instantaneous flood delineation. Proposed physical interventions involve the establishment of new sluices, refurbishment of pump houses, and the erection of flood embankments, while non-structural actions emphasize prompt warning systems, land utilization supervision, and community enlightenment. This holistic approach accentuates the significance of community responsibility, regional proficiency, and sustainable developmental techniques in augmenting flood resilience. The findings aim to enhance the wider conversation on disaster risk reduction and provide practical solutions for managing flood hazards in the Gin River Basin.