Germany's global water consumption under consideration of the local safe operating spaces of watersheds worldwide

Germany is one of the five largest consumer markets in the world. Given that both supply chains and water consumption in agriculture, industry and underlying resource extraction and energy generation are globally intertwined, consumption in Germany undeniably has a major impact on global water consumption. This paper aims to determine Germany's global consumption-induced water consumption (hereinafter water consumption), with a particular focus on the worldwide origin of the country's blue water consumption at a watershed level and under consideration of the local safe operating spaces of watersheds. First of all, an approach based on environmentally extended multi-regional input-output analysis (EE-MRIO) was used to determine the origin of national contributions to Germany's water consumption. The resulting national contributions were then allocated to 8250 watersheds worldwide, weighted by consumption, and benchmarked against their local safe operating spaces. In this study, Germany's water consumption in 2015 was approximated to 171 ​km3 (6 ​m³⋅capita-1⋅day-1), 14.4 ​km³ of which was blue water. Other countries contributed more than 80% of Germany's blue water consumption. India, Pakistan and Egypt contributed more blue water to Germany's blue water consumption than Germany itself; virtual water imports from the Indus, Nile, Ganges and Mississippi river basins alone accounted for more than a quarter of Germany's total blue water consumption. Taking into account the local safe operating spaces of watersheds worldwide, more than 15% of Germany's external blue water consumption is deemed to exceed the local safe operating spaces of the contributing watersheds. Overall, the results are in line with previous studies of Germany's water footprint, albeit offering unprecedented spatial detail and hence new scientific substantiation for environmental policy-making. Moreover, the method applied, which can be transferred to other types of scientific analysis, shows how spatially explicit water consumption results can be derived from EE-MRIO-based analyses, even at the subnational level.