GLOWA Elbe III: Impacts of global change on the hydrological cycle of the Elbe River Basin
Results and consequences
Impacts of water scarcity on economy and society in the Elbe River Basin: Results from GLOWA-Elbe
GLOWA-Elbe is concerned with the impacts of global change, in particular climate and demographic change, on water availability in the Elbe River Basin. The aim of this project is to identify water use conflicts, to assess economic losses caused by water scarcity, to develop suitable adaptation strategies, and to evaluate these strategies from an economic point of view. Economic impacts of water scarcity and adaptation strategies are assessed for the entire Elbe River Basin and for different disaggregated levels, e.g. sub-basins, individual time periods until the year 2052, and for individual water users. Scenarios are employed to handle uncertainties arising from the relatively large time horizon. A range of models was used to analyse scenarios of climatic and socio-economic developments. These include models to predict climate, water management, population, land-use and water demand.
The main results are:
- Agricultural irrigation, wetlands, freight and recreational shipping as well as hydro power generation are the most affected water users. These are water users that either directly depend on river discharge and/or face high levels of evaporation. At the same time they have little adaptive capacities to cope with reduced water availability.
- Interestingly, water-intensive water users such as drinking water provision, industry and power plants are hardly affected by water scarcity. Explanations for this are that water demand tends to decrease in these sectors due to technological developments. E.g. the introduction of closed-circuit cooling in the power plant sector leads to serious reductions in water demand. These water users have capacities to adapt to water scarcity.
- From a spatial point of view, it can be stated that the Havel sub-basin is likely to face large economic consequences. In the entire river basin economic losses will concentrate on few individual water withdrawal points. In dry years, only about half of these water withdrawal points in the Elbe River Basin will face an economic loss and less than 20% will bare the overall loss. Exceptions are hydro power plants and wetlands. Here almost all water withdrawal points are affected by reductions in water availability.
- The findings suggest that there will be no area-wide increase in water scarcity in the Elbe River Basin. However, individual water users and regions are likely to be seriously affected. Furthermore, water users that are already affected by water scarcity in dry summers, e.g. freight shipping, have to expect a further increase in water deficits. With respect to the development of adaptation strategies, this means that one should concentrate on problems that already occur today.
Adaptation strategies have been identified in collaboration with stakeholders. Adaptation is possible in the following fields: Reservoir management, water transition, wetland management and demand management in public water utilities. The economic impacts and costs of these adaptation strategies will be analysed until the end of the GLOWA-Elbe project in October 2010.