A Decomposition and Comparison Analysis of International Water Footprint Time Series

This paper deals with the construction, decomposition and comparison of water footprint time series in 40 countries and one aggregate macro-region, in the period 1995-2009. The analysis of the different “footpaths” allows us to investigate on the possible causes behind the time evolution of water footprints in the various countries. We notice that the physical and economic impact of economic growth on water resources has been significantly lower than what it could have been, for several reasons. First, both production and consumption patterns are shifting away from water intensive goods. Second, a large part of consumed water is actually not blue water, susceptible of alternative uses. Finally, we do not find strong evidence of gains in the economic productivity of water (dollars per water unit) in many countries, but we do find evidence of indirect efficiency gains, related to the composition of factors in the production processes.