PhD defence: Rena Meyer

Rena Meyer defends her thesis,

Large scale hydrogeological modelling of a low-lying complex coastal aquifer system

Supervisors:
Professor Peter K. Engesgaard, IGN
Affiliated Professor Torben Sonnenborg, IGN

Assessment Committee:
Professor Gudrun Massmann, University of Oldenburg - Germany
Research Associate Vincent Post, BGR Germany and Flinders University - Germany
Associate Professor Søren Jessen (chair), IGN

Summary:
Aquifers in low-lying coastal areas are vulnerable to saltwater intrusion because of the naturally low head gradient, high groundwater abstraction rates and land management. The problem is expected to intensify in future because of increasing freshwater demand concomitant with population and economy growth and relative sea level rise as a consequence of climate change. Groundwater modelling provides a tool to support sustainable water management and mitigating the risk of saltwater intrusion. In the transboundary region between Southern Denmark and Northern Germany, adjacent to the Wadden Sea, a large-scale saltwater intrusion reaching up to 20 km inland is observed. It is unknown how the saltwater intrusion developed to its present extent and how it will affect the aquifer system in the future, expecting the sea level to rise due to climate change. In order to gain insight into the regional groundwater flow system and to identify the driving mechanisms that formed the saltwater intrusion to its present extent and how it might develop in the future, 3D numerical groundwater modelling combined with a detailed geological description and hydrological, geochemical and geophysical data was applied.
Insight was gained into the driving features of the regional flow system that comprises both human alternations to the hydraulic system and the specifications of the (hydro)geological setting. These features also control the formation of the saltwater intrusion both in the past and the future.

The thesis is available for inspection from the PhD Administration office, 04.1.413.