Do the Ruhr reservoirs have sufficient capacity to ensure the future supply of the population in the Ruhr region and the Sauerland with water? Against the background of possible climate change, the Ruhrverband has recently commissioned a climate change impact analysis to look into this question. The calculations revealed that in the worst-case scenario, the supply will be 99.5 per cent safe - as opposed to 99.8 per cent at the moment. Statistically, that means that in 199 out of 200 years, the reservoirs can provide enough water to supply the region.
The research institute commissioned by the Ruhrverband based its analysis on two regional climate models forecasting a temperature increase of around three degrees centigrade by 2100. While total annual precipitation is projected to remain roughly the same, dry periods in the summer may become more intense with heavier precipitation in winter. However, the two climate models come to different conclusions regarding the scope of this shift. The analysis thus outlines a trend for the effects of climate change on supply security by Ruhrverband reservoirs.
As regional climate models can be expected to become more precise in the future, the Ruhrverband will include any new findings in the calculations for its system of reservoirs. In fact, the Ruhrverband has already started to look for strategies to optimise the operation of its reservoirs in order to be able to meet the potential effects of climate change as early as possible. In this context, the Ruhrverband with support from the North Rhine-Westphalian Ministry of the Environment has recently commissioned another study which currently investigates the flood control effect of its reservoirs in changing climatic conditions.