Furthermore, a water footprint calculator for individuals (based
on their nation, diet, income, and gender) is available on the
internet (see www.waterfootprint.org). The calculation of WFs is
often related to the concept of “virtual water” or entire volume of
freshwater that is “expended” throughout the chain of production
required for goods and services consumed ([Allan, 1998] and
[Rogers, 2008]).1 Water footprints explicitly calculate regional
water consumption by subtracting virtual water estimates for
exports from those for total local production and then add virtual
water “embedded” in imports to the region under study (as shown
in Hoekstra’s and Hung’s (2002) example of crop trade). For
a description of the WF calculation and a comparison between the
EF and the WF, please refer to Hoekstra (2008).