Flood damage estimation: knowledge gained from field surveys

Flooding has been increased significantly in all over the world from the past few years because of the climate change and economic losses due to flooding have been increased more significantly from the last few decades. It is necessary to estimate the flood losses in the domain of flood risk management and to adopt the best practices for the collection, storage, and analysis of the flood damage data in order to develop the risk mitigation strategies for the severe flood events. In this study, one of the best practices has been presented for the collection and estimation of the flood damage data of the residential buildings through field surveys. In this regard, the study was divided into two phases: (1) introduction of the pilot study for the understanding of real field conditions, identifying the strengths and weaknesses in the survey questionnaire, and improving the field strategy; and (2) organization of the detailed study based on the previous experience of the pilot study and conducting field surveys on a large scale by adopting improved field strategy through a well-structured paper-based survey questionnaire. Through field surveys, the data for socio-demographic characteristics and damage information including building features, hazard variables, building damage cost, building damage extend, financial compensation, precautionary measures, and warning systems of the population was collected. The collected flood damage data was encoded in the Moodle and the python script was used for decoding any errors between encoding and verification phases based on a timestamp and mostly graphs were generated based on readily available python scripts. The analysis and the interpretations of the graphs have been done for developing the relationships and dependencies between different variables and building features and conclusions have been drawn at the end of this study.