Water footprint
Encyclopedia
The water footprint of an individual, community or business is defined as the total volume of freshwater used to produce the goods and services consumed by the individual or community or produced by the business. Water use is measured in water volume consumed (evaporated) and/or polluted per unit of time. A water footprint can be calculated for any well-defined group of consumers (e.g. an individual, family, village, city, province, state or nation) or producers (e.g. a public organization, private enterprise or economic sector). The water footprint is a geographically explicit indicator, not only showing volumes of water use and pollution, but also the locations.. However, the water footprint does not provide information on how the embedded water negatively or positively affects local water resources, ecosystems and livelihoods.

History

The water footprint concept was introduced in 2002 by A.Y. Hoekstra from UNESCO-IHE
UNESCO-IHE
The UNESCO-IHE Institute for Water Education is an international institute for water education that was created in 2003 from the previous IHE. This in turn grew out of the International Course in Hydraulic Engineering , whose name was changed in 1976 to International Institute for Hydraulic and...

 as an alternative indicator of water use.. The concept was refined and accounting methods were established with a series of publications from two lead authors A.K. Chapagain and A.Y. Hoekstra from the UNESCO-IHE Institute for Water Education, now at WWF-UK and University of Twente respectively. The most elaborate publications on how to estimate water footprints are a 2004-report on the 'Water footprint of nations' from UNESCO-IHE and the 2008-book Globalization of Water by A.Y. Hoekstra and A.K. Chapagain, published by Blackwell, 2008. Cooperation between global leading institutions in the field has led to the establishment of the Water Footprint Network in 2008 that aims to coordinate efforts to further develop and disseminate knowledge on water footprint concepts, methods and tools.

Blue, green and grey water footprint

A water footprint consists of three components: the blue, green and grey water footprint. The blue water footprint is the volume of freshwater that evaporated from the global blue water resources (surface water and ground water) to produce the goods and services consumed by the individual or community. The green water footprint is the volume of water evaporated from the global green water resources (rainwater stored in the soil as soil moisture). The grey water footprint is the volume of polluted water that associates with the production of all goods and services for the individual or community. The latter can be estimated as the volume of water that is required to dilute pollutants to such an extent that the quality of the water remains at or above agreed water quality standards.

Water footprint of individual consumers

The water footprint of an individual consumer refers to the sum of direct and indirect freshwater use by the consumer. The direct water use is the water used at home. The indirect water use relates to the total volume of freshwater that is used to produce the goods and services consumed by the consumer.

The global average Water Footprint is 1240 m³ water/person/year. The Chinese average is 700 m³ water/person/year one of the smallest in the world and the United States's 2480 m³ water/person/year is the largest in the world. which is published in a concise form in a journal The Finnish average Water Footprint is 1730 m³ water/person/year.. The water footprint of the UK is 1695 m³ water/person/year.

Water footprint of businesses

The water footprint of a business, the 'corporate water footprint', is defined as the total volume of freshwater that is used directly or indirectly to run and support a business. It is the total volume of water use to be associated with the use of the business outputs. The water footprint of a business consists of two components: the direct water use by the producer (for producing/manufacturing or for supporting activities) and the indirect water use (in the producer’s supply chain).

Water footprints of nations

The water footprint of a nation shows the water that is used to produce the goods and services consumed by the inhabitants of the nation. It includes two components: the internal and the external water footprint. The first component refers to the appropriation of domestic water resources; the latter to the appropriation of water resources in other countries. About 65% of Japan's total water footprint comes from outside the country; about 7% of the Chinese water footprint falls outside China.

Water footprint calculation standard

Since 2009 there is a global calculation standard for the water footprint, maintained by the Water Footprint Network, an international network of governments, corporations, non-governmental organizations and UN bodies.

Criticism of the water footprint concept

Due to the recent spread of the water footprint as an indicator of water use, application and interpretation of the results may sometimes be performed to promote industrial activities that lead to facile criticism of certain products without discussing the results in further detail. The 140 litres required for coffee production for one cup might be of no harm to water resources as its cultivation occurs mainly in humid areas but could be damaging in more arid areas. Nevertheless, the resulting figures suggest the sum of water quantities as an environmental concern. This concern that may not always be justified given a region's specific set of factors, such as hydrology, climate, geology, topography, and so forth. Moreover, halting the production of coffee in that region may have a detrimental affect on incomes and livelihoods.

According to water economics expert Dennis Wichelns from the International Water Management Institute
International Water Management Institute
The International Water Management Institute is a non-profit research organisation with headquarters in Colombo, Sri Lanka, and offices across Africa and Asia...

: Although one goal of virtual water analysis is to describe opportunities for improving water security, there is almost no mention of the potential impacts of the prescriptions arising from that analysis on farm households in industrialized or developing countries. It is essential to consider more carefully the inherent flaws in the virtual water and water footprint perspectives, particularly when seeking guidance regarding policy decisions.

Recently, the concept has been criticized for the term "footprint," which can confuse people familiar with the notion of a carbon footprint
Carbon footprint
A carbon footprint has historically been defined as "the total set of greenhouse gas emissions caused by an organization, event, product or person.". However, calculating a carbon footprint which conforms to this definition is often impracticable due to the large amount of data required, which is...

 since the water footprint concept, as described above, includes sums of water quantities without necessarily evaluating related impacts. This is in contrast to the carbon footprint, where carbon emissions are not simply summarized but normalized by CO2 emissions, which are globally identical, to account for the environmental harm. The difference is due to the somewhat more complex nature of water; while involved in the global hydrological cycle, it is expressed in conditions both local and regional through various forms like river basins, watersheds, on down to groundwater (as part of larger aquifer systems).

See also

  • Carbon footprint
    Carbon footprint
    A carbon footprint has historically been defined as "the total set of greenhouse gas emissions caused by an organization, event, product or person.". However, calculating a carbon footprint which conforms to this definition is often impracticable due to the large amount of data required, which is...

  • Ecological footprint
    Ecological footprint
    The ecological footprint is a measure of human demand on the Earth's ecosystems. It is a standardized measure of demand for natural capital that may be contrasted with the planet's ecological capacity to regenerate. It represents the amount of biologically productive land and sea area necessary to...

  • Virtual water
    Virtual water
    Virtual water refers, in the context of trade, to the water used in the production of a good or service. For instance, it takes 1,300 cubic meters of water on average to produce one metric tonne of wheat. The precise volume can be more or less depending on climatic conditions and agricultural...

  • Water crisis
    Water crisis
    Water crisis is a general term used to describe a situation where the available water within a region is less than the region's demand. The term has been used to describe the availability of potable water in a variety of regions by the United Nations and other world organizations...

  • Deficit irrigation
    Deficit irrigation
    Deficit irrigation is a watering strategy that can be applied by different types of irrigation application methods. The correct application of DI requires thorough understanding of the yield response to water and of the economic impact of reductions in harvest...

  • Water resources of China
    Water resources of China
    The water resources of China are abundant on average, but are scarce in some regions. About 80% of all water resources are in one river basin, the Yangtze. Water is scarce around Beijing, where groundwater is overexploited. Agriculture is the major water user accounting for 78% of water use...

  • China water crisis
    China water crisis
    The Chinese water crisis threatens the stability and prosperity not only in People's Republic of China but globally as well, according to John McAlister from the film Aquabiotronics. According to the World Bank forecast, Mainland China has only a per-capita share of 2700 cubic meters per annum,...


Water footprint websites






Consultants active in Water Footprint Assessments



Water footprint calculators

Online water footprint calculators are available:



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