Usefulness in policy formulation The Water Footprint: • Endows water resource management and governance with a new global dimension; •
Enables nations to gain a better understanding of their dependence on water resources beyond their own frontiers;
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Offers river basin management authorities more precise information on scarce water resources that are being allocated for products being exported with low financial value;
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Suggests to companies ways they can monitor their dependence on scarce water resources along the length of their supply chains and in their production processes;
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Demonstrates the unequal distribution of water resource use and the need to implant international policies stimulating equilibrium in water resource use among the different countries.
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Promotes a discussion of the need for international policies directed at reducing water resource consumption.
Positive Aspects The Water Footprint presents a spatial distribution chart of a country’s water resource demands. It expands traditional analyses restricted to ‘water extraction’ by including the categories of green and grey water. It visualises the connections between local consumption and the global appropriation of fresh water. It also integrates water use and water pollution as elements of the production chain. Negative Aspects The Water Footprint only analyses human demands for water and not the demands of the ecosystems as a whole. It depends on local data that is often unavailable or difficult to collect. It is liable to truncation errors in the calculations. No studies have been done regarding data uncertainties although they are known to be significant. Calculations of ‘grey’ water rely heavily on estimates and suppositions.
The Ecological Footprint of São Paulo - State and Capital 2012 p.
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