Drain for Gain: Making Water Management Worth its Salt: Subsurface Drainage Practices in Irrigated Agriculture in Semi-arid and Arid Regions

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.

Henk Ritzema received his MSc degree from the Department of Civil Engineering at Delft University of Technology in 1980. After graduation, he worked for the Food and Agriculture Organization of the UN and the Dutch Civil Service. In 1989 he joined the International Institute for Land Reclamation (formerly ILRI, now Alterra), Wageningen. In 2008 he joined the Irrigation and Water Engineering Group at Wageningen University.