Salt Intrusion, Tides and Mixing in Multi-Channel Estuaries PhD: UNESCO-IHE Institute, Delft

Multi-channel estuaries, such as the Mekong Delta in Vietnam and the Scheldt in the Netherlands, have characteristics of both the river and the sea, forming a unique environment influenced by tidal movements of the sea and freshwater flow of the river. This study addresses a number of knowledge gaps in multi-channel estuaries by developing a predictive analytical approach for salinity intrusion and discharge estimate in multi-channel estuaries. The new approach agrees well with 1-D hydrodynamic models and observations, indicating its applicability in practice. Most importantly, the study has successfully developed a new theory and a new equation to quantify tidal pumping due to ebb-flood channel residual circulation and the related salt dispersion.

CONTENTSPrefaceSummary1 Introduction2 Salt intrusion, Mixing and Tides in estuaries3 Salt intrusion in multi-channel estuaries 4 Discharge distribution over estuary branches5 Tidal characteristics in multi-channel estuaries6 Mixing in estuaries with an ebb-flood channel system7 Conclusions and Recommendations

Nguyen Anh Duc (1976) graduated from Ho Chi Minh City University of Architecture, majoring in Building Construction and Industrial Structures in 1999. In 2001 he obtained a post-graduate scholarship at UNESCO-IHE, Delft, The Netherlands and received his MSc degree (with distinction) in June 2003 on a thesis entitled: "Flood Management Strategies: A case study in the lower Dong Nai - Sai Gon river system, Vietnam". In 2004 he started his PhD research at UNESCO-IHE on Salt Intrusion, Mixing and Tides in Alluvial Estuaries, resulting in this dissertation.