Long-term trends in groundwater management of alpine catchments
For many municipalities in Austria groundwater is the most important drinking water resource. Therefore long-term fluctuations in groundwater levels are a matter of public interest. The quantitative status of aquifers depend on a number of natural and anthropogenic factors. On the one hand, precipitation donation and infiltration rate determine groundwater recharge. Especially the infiltration rate is subject to strong changes, due to the increasing sealing of areas. At the same time, new wells and drainage systems counteract groundwater recharge and influence local currents. Budget planning of states and counties therefore lay down sustainable groundwater management plans with the aim of long-term stabilisation of the aquifers.
In the municipality of Rif near Salzburg, continuously rising groundwater levels have been observed since the 1980s. For the affected population and the authorities, it is of interest which climatic or anthropogenic changes justify this trend. The GroWaT (GroundWater Trends) project uses calibrated, numerical models to investigate future groundwater flows in the catchment area. The most important step is a balanced model calibration of the actual state, which includes variable boundary conditions of surface waters, as well as the hydraulic parameterisation. For the definition of the parameters, current hydrogeological models are evaluated and optimized using geostatistical simulation tools. In a second step, the variables of the model such as climatic input, hydrological boundary conditions, underground constructions and discharge parameters are varied and model scenarios are computed. These provide information on the sensitivity and relevance of the tested parameters and can provide indications on the long-term changes of the aquifer.
The GroWaT project was launched on the initiative of the state of Salzburg. The aim is to identify sensitive climatic and settlement developments that have a quantitative impact on groundwater aquifers and to calculate impacts of countermeasures.
Contribution GEORESEARCH: Project Lead
Project Partners: Land Salzburg, GEOCONSULT ZT GmbH, Joanneum Research, Marschallinger Geoinformatik, Ingenieurbüro WÖLFLE ZT-GmbH, Salzburg AG, ZAMG
Project Duration: July 2018 - December 2019
Funding: Land Salzburg