A universal and equitable access to clean water and drinking water for all people is at the forefront of Objective 6 of the UN’s 17 new sustainable development goals (SDG) to reduce hunger and extreme poverty worldwide (UN, 2016). Therefore, the improvement of water utilization efficiencies and the conservation of existing water resources should be a priority.
Sustainable water use requires the assessment of water resources, based on a combination of hydrological information, feasibility studies, identification of the sensitivity of an area to water stress, and assessment of sensitivity to external stress factors.
The European Commission points to significant weaknesses in the risk assessment of karst aquifers. Especially the karst regions of the Mediterranean have a high variability due to their complex geomorphology and active erosion processes, so that statements and risk assessments are often difficult to transfer from one region to another. Karst aquifers are particularly vulnerable to climate change. Over the last 20 years, the economic impact of droughts in the Mediterranean region has exceeded the economic impact of the droughts in the US by five times. Based on this hydrological sensitivity of carbonated aquifers, the European Commission calls for improved risk assessment and increased protection of these aquifer systems.
The first solution approaches for improved risk assessment and sustainable water use are the use of process-based forecast models (e.g. hydrological models, ecosystem models, landscape dynamics models, dynamic global vegetation models, optimization models). These models often differ in their spatial-temporal resolution, their calculation of water flow and soil moisture, their consideration of climatic variability and hydrology, as well as their accuracy of the representation of processes in the soil and its feedback with the vegetation. In this context, especially radar-based remote sensing data provide valuable information for the generation of area-based input data for sufficiently calibrated groundwater models at regional as well as global levels. In particular, the soil water index (SWI) offers a high potential for describing model boundary conditions. At present there are only a small number of models for the Mediterranean region, which are able to calculate the water balance with regard to changes in agricultural production, land use management, the importance of water exports and climate change.
In the MedWater project, forecast models of the resource systems represent a central component for a “real-time” optimization and they allow:
- the quantitative and thus objective analysis of the systems,
- the prognosis of the short and long term development of the systems as a function of external factors (such as climate, technology development and socio-economic conditions),
- the assessment of different water usage and water distribution strategies;
- the identification of the integrated optimization approaches adapted to specific geographic, social, financial and environmental constellations.
The development of a real-time model-based and indicator-based optimization concept in the water resource management will provide the basis for the implementation of an improvement in water efficiency, conservation of existing water resources and access to water resources by all population groups.