Conference Agenda

Ensuring a safe and affordable water supply is key to ensuring growth and avoiding or mitigating conflicts on our planet in the face of climate change. Similarly, sustainable cities and communities require sufficient and clean water, and sustainable ecosystems can only thrive if agriculture and land use are not threatened by water scarcity or catastrophic overabundance. Traditionally, groundwater modelling has focused on supply issues related to specific regions, complemented by the assessment of water chemistry. Coming originally from regional to basin scale studies of coupled heat and fluid transport in the subsurface to predict geothermal potential, we began to analyse transient three-dimensional groundwater flow as a by-product of these hydrothermal models. Our workflow is to integrate geoscientific observations and physics-based simulations into digital twins of the subsurface that predict the heterogeneous distribution of physical properties in the subsurface as well as the coupled thermo-hydraulic (-mechanical) processes occurring there. By applying the simulation tools to the data-derived three-dimensional models, we can predict, for example, how fast groundwater flows at different depths and in different lithologies, and what this means for contaminant transport or groundwater salinity. Other questions relate to the connection between surface water and groundwater, changes in groundwater dynamics in response to glaciation or climate change, and associated changes in precipitation and recharge also connected to anthropogenic overprinting. We illustrate with examples why addressing such issues is key to enabling sustainable use of the subsurface and mitigating the consequences of global change.