Modelling groundwater systems : understanding and improving groundwater quantity and quality management; Dissertation, UNESCO-IHE Institute for Water Education, Delft.

Groundwater is an essential natural resource. It is the main source of water supply for domestic consumption, agriculture, and industrial development in many parts of the world. Besides that it is of vital importance for securing biodiversity of ecosystems. Yet, the resource is threatened by excessive over-exploitation and by contamination mainly resulting from industrial activities and agricultural practices. Increasing demands due to an increase in population and climate change further exacerbate the problem, and hence further development of groundwater resources and efficient protection against over-use and contamination remains a practical concern for water resources managers. In order to properly manage this vital resource, understanding its behaviour when subjected to external stresses is of significant importance. This thesis explores several specific groundwater management problems related to contaminant migration, groundwater-surface water interactions and managed aquifer recharge, using a variety of simulation methods and combined simulation-optimization modelling approaches. The capabilities and limitations of these approaches for evaluating groundwater quantity and quality management options are explored. Case studies were performed on field applications in Belgium, Germany and Oman. The results of these studies demonstrate that better insights and improved groundwater resource management can be achieved through a combination of different simulation and optimization methods that take into account data availability and specific site conditions