Program: Collaborative Research for Common Regional Issues (CRC)
Field: Natural Disaster
Principal Investigator: Dr. BUI Trong Vinh
Sending University: Ho Chi Minh City University of Technology (HCMUT)
Japanese Co-Investigator: Prof. Dr. Shinichi AOKI
Japanese University: Osaka University
Mekong River Delta and other low-land coastal regions in ASEAN countries such as Indonesia, Thailand, and the Philippine have been eroded and retreated severely. These regions are highly vulnerable to extremely events such as typhoon, high waves, strong currents, sea-level rise and improper human activities.
Mangrove ecosystems have been threatened and disappeared due to starved sediments, deforestation, and contaminants from river into coastal water. In recent years, many engineering structures such as dams, river ports, and channelization constructed in upstream of Mekong River have reduced sediment supply to Mekong River Delta. Sand mining and dredging in large rivers and around river mouth have also reduced sediment supply to the coasts and changed water circulation patterns, nutrient delivery. Degradation of this system has serious implications for the residents living in low-land coastal regions like social-economic costs and environmental impacts.
Tien Giang Province is one of the low-land coastal provinces of Mekong River Delta (Fig.1). On the report of Department of Agricultural and Rural Development, the coastal area of the province is in the east and extends around 32 km. Before Vietnam War, the width of mangrove fringe was thousands of meters from the coastline. During the war (from 1969 to 1972), many mangrove areas were destroyed by defoliants sprayed by the US Army. After the war (from 1975 to 1978), due to lack of management, many more mangrove trees had been cut down for fuel wood, constructing materials etc. From 1980 up to now, the Vietnamese government has established the programs such as No.327, and No. 661 to replant mangrove trees. However, the mangrove areas in some places have still been lost. Many places have been threatened severely by typhoon, strong waves and tidal currents. On the other hand, Soai Rap River have been dredged for large ships to navigate to Hiep Phuoc Port and other important ports in Sai Gon River. This work has reduced sediment supply to the coast. The erosion rates of the low-land coastal regions have been 8 – 10 meters per year within the last ten years. The old sea dykes have been collapsed and threatened to over 300.000 residents living behind the sea dykes.
The main objectives of the research projects are to:
– Evaluate the effects of development, preservation, and disaster prevention and mitigation on coastal erosion in Mekong River Delta with additional perspective on similar evaluation on selected sites of ASEAN countries
– Investigate the present severe conditions such as typhoon, high wind waves and tidal currents which impact on low-land coastal regions of Mekong River Delta
– Understand erosion mechanism and sediment transportation to restore mangrove forest and ecosystem
– Propose the mitigation and prevention strategies to the coastal disasters including non-structures approaches (management policies, resident education, technical guidelines) and structure approaches (soft structures and hard structures)
(Source: Application to CRC 2014)