Flood management strategies : a case study in the lower Dong Nai-Sai Gon river system : Vietnam

The lower Dong Nai - Sai Gon river system is a zone with plentiful natural resources and it has the highest economic development rate in Vietnam, especially the Southern Focal Economic Area (SFEA) including Ho Chi Minh city, Dong Nai and Ba Ria Vung Tau provinces. The lower Dong Nai - Sai Gon river area has the highest density of population in Southern Viet Nam, with more than 11 million people in total. However, as a typical transition area between a sea and rivers, the area is flat and low-lying, suffering from river flooding and inundation due to heavy rain and high tides. In the past, the area experienced some exceptional floods which brought about serious damages to private house and properties, public facilities, agricultural crops and live stock. Coping with floods is the objective of this Master of Science study. During eight months of the intensive study, the flood issues of the lower Dong Nai - Sai Gon river system were examined and analized carefUlly and broadly by a comprehensive methodology. The methodology mainly base on (i) the analysis for simulated results of flood conditions in one-dimensional hydrodynamic model SOBEK-RURAL accompanied with GIS database. (ii) development of integrated flood management strategies with full considerations for existing environmental system of the study area as well as for the modern concepts of flood management and mitigation. A river system schematization in SOBEK - RURAL mqdel was developed to explore future flood situations. The flood risks, potential damages and•• losses for the future flood situations were analized based on GIS data in Maplnfo and ArcView. Finally, various flood management strategies were developed to cope with flood issues and to explore their feasibility by analyzing hydraulical, environmental and economical impacts in a broad scope. The results of the study reveal that the flood issues in the lower Dong Nai - Sai Gon river system might be substantially managed and mitigated by some promising integrated management strategies, which are the combination of various structural measures and their appropriate non-structural measures. Despite of some constraints and limitations related to data and knowledge, finally, it can be said that the study has been achieved its objective. Hopefully, the study results will contribute to the development of sustainable flood management programme's in the lower Dong Nai - Sai Gon river system. It has definitely contributed to the author's knowlegde and profesional career