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Reliability of coastal flood defences in Vietnam

C. MAI VAN^1,2, P. H. A. J. M. VAN GELDER¹ & J. K. VRIJLING¹

1 Delft University of Technology, Stevinweg 1, 2628 CN Delft, PO Box 5048, 2600 GA DELFT, The Netherlands

c.maivan@tudelft.nl

2 Water Resources University of Vietnam, 175 Tayson, Dong Da, Hanoi, Vietnam

Abstract This research aims at investigating the safety aspects of coastal flood defences in Vietnam, a country which has coastlines of about 3000 kilometres long, with low lying deltaic coastal areas, which are mainly protected by sea dikes. The sea dikes in particular are threatened because of the combined occurrence of severe storm surges from the sea and its high tides. An accurate assessment of the safety of the existing coastal defence system is therefore important. Application of modern probabilistic techniques for safety assess­ment of coastal flood defences is investigated. Subsequently, determination of the accepted risk level in the coastal areas is discussed. The reliability and risk-based optimal design for improvement of the Vietnamese coastal flood defence system is presented.

Key words coastal defences; flood defences; probabilistic design; reliability of coastal structures; risk analysis; sea dikes