Présentations Colloques

Oral Presentation
Session 8.10: Recent developments in groundwater modeling and mathematical tools in Hydrogeology
Barthel Roland
Characterising status and changes of regional scale groundwater systems using similarity
Regional hydrogeology is becoming increasingly important, but at the same time, scientifically sound, universal solutions for typical groundwater problems encountered on the regional scale are hard to find (Barthel, 2014+ Barthel and Banzhaf, 2015). One of the main challenges encountered on the regional scale in hydrogeology is the extreme heterogeneity that generally increases with the size of the studied area - paired with relative data scarcity. Assessing the status and predicting the behavior of groundwater systems under conditions of global change is typically done by using rather coarsely discretized and or poorly parameterized numerical models, or by using very simplistic conceptual hydrological models that do not take into account the complex three-dimensional geological setup. Numerical models heavily rely on local data and are resource-demanding. Conceptual hydrological models only deliver reliable information on groundwater if the geology is extremely simple.****In this contribution, we present an approach to derive statistically relevant information for un-monitored areas, making use of existing information from similar localities that are or have been monitored. The approach combines site specific knowledge with conceptual assumptions on the behavior of groundwater systems. It is based on the hypothesis that similar groundwater systems respond similarly to similar impacts. At its core is the classification of (i) static hydrogeological characteristics (such as aquifer geometry and hydraulic properties), (ii) dynamic changes of the boundary conditions (such as recharge, water levels in surface waters), and (iii) dynamic groundwater system responses (groundwater head and chemical parameters). The dependencies of system responses on explanatory variables are used to map knowledge from observed locations to areas without measurements. This contribution focusses on the main hydrogeological concepts underlying the approach.****References-**Barthel, R., 2014. A call for more fundamental science in regional hydrogeology. Hydrogeol J, 22(3)- 507-510. **Barthel, R., Banzhaf, S., 2016. Groundwater and Surface Water Interaction at the Regional-scale – A Review with Focus on Regional Integrated Models. Water Resour Manag, 30(1), 1-32.****