Hydromix

Impact of surface water management on groundwater quality in Alpine catchments

In this project, we aim at investigating how surface water management in Alpine catchments affected by strong anthropogenic impacts controls subsurface flow at multiple spatial and temporal scales.

The interaction between surface water and groundwater is of pivotal importance in many fields of science and engineering. Quantifying the fluxes between these two environmental compartments is of practical relevance, for example, to delineate appropriate water resources management strategies, to perform water quality assessment and to understand ecosystem dynamics and functioning. Extensive research has been hence performed in the past in order to quantify the exchange of water between aquifers and surface water bodies in several diverse catchments worldwide.

The novelty of the proposed research lays in the investigation of
i) the impact of surface water management in Alpine catchments on groundwater flow in alluvial aquifers
ii) the influence of highly transient interface transmission conditions on the topology of the two dimensional and three dimensional groundwater flow fields
iii) the development of accurate inversion numerical schemes for the solution of flow and transport equations under highly transient boundary conditions
iv) the quantification of the uncertainty related to model prediction considering both hydrogeological parameter uncertainty as well as the uncertainty affecting transient interface conditions.

Specific scientific goals of the proposed research work are:

• to develop numerical methods to perform auxiliary calculations to flow simulations (building on top of state-of-the-art software) to aid in sensitivity/uncertainty analysis (e.g. a posteriori error estimates/derivative estimates) and to reproduce appropriately flow at the field scale at reasonable computational costs. 
• to quantify the uncertainty of predicted flow fields considering both parameter uncertainty as well as uncertainty in the interface conditions using state-of-the-art analyses techniques including new goal-oriented sampling techniques and dimension-reduction techniques that efficiently allocate computational resources.
• to use the validated numerical model to investigate flow topology in complex three-dimensional transient flow fields in non-stationary heterogeneous and anisotropic aquifers.
• to characterize the topological and kinematic properties of 3-D and 2-D transient flow fields identifying relevant metrics to predict plume deformation in 3-D and 2-D transient flow fields.
• to determine mixing properties of flow fields in real heterogeneous, anisotropic porous aquifers in which groundwater flow is influenced by river stage fluctuations at multiple temporal scale.
• to aid in the design of field experiments so that resources are allocated optimally.

 

Project duration: April 2019 - March 2025
Project funding: German Research Foundation (DFG)
Project management: Prof. Dr. Gabriele Chiogna, Prof. Dr. Barbara Wohlmuth