The water footprint necessarily has a temporal dimension and a spatial dimension. It must be calculated with data collected in a specific period of time (usually the data used is annual) and in a perfectly delimited geographic location (such as an industrial plant, a river basin, or a region). The water footprint is a geographically explicit indicator, showing not only volumes of water use and pollution, but also locations.[4]​ However, the water footprint does not provide information on how the water consumed positively or negatively affects local water resources, ecosystems and livelihoods.

Direct consumption for the manufacture of a product includes the water used and/or contaminated during the manufacturing process and the water incorporated into the product itself as an ingredient. For its part, indirect consumption corresponds to all the water necessary to produce the different raw materials used in the process (supply chain products).

The water footprint can also be expressed in colors, depending on the type of water considered:

• - Green water footprint: related to the rainwater incorporated into the product.

• - Blue water footprint: related to the consumptive use of evaporated freshwater (surface or underground).

• - Gray water footprint: related to the quality of the water and its possible contamination due to discharges.

The International Standard ISO 14046:2014 defines “Water footprint assessment: compilation and evaluation of inputs, outputs and potential environmental impacts related to the water used or affected by a product, process or organization” and presents a method based on Life Cycle Analysis (LCA) defined by the International Standard ISO 14044.

The water footprint or water footprint as opposed to virtual water, and the Water Footprint Network classifies water sources, that is, it distinguishes between three components: blue water, green water and gray water. This classification, especially gray water, has suffered criticism and is not contemplated in the International Standard ISO 14046:2014. The blue water footprint is the volume of fresh water consumed from the planet's water resources (surface and groundwater). The green water footprint is the volume of water evaporated from the planet's water resources (rainwater stored in the soil as moisture). The gray water footprint is the volume of contaminated water that is associated with the production of goods and services. The latter can be estimated as the volume of water that is required to dilute contaminants to the point that water quality is maintained at or above agreed water quality standards. The units in which these indicators work depend on the type of sector for which the water footprint is measured. Thus, for example, the water footprint of a meat product On the other hand, the water footprint of an individual can be measured in [m/year], representing the amount of water consumed over time. This indicator can support efficient improvements in water management and be a good support for raising awareness about our water consumption.

The Netherlands and Spain have shown great progress in the practical development of the water footprint.

To calculate the Footprint of a country, whether water, carbon or ecological, Input-Output analysis is widely used since it is of great help regarding the Life Cycle of Products at a macro level.[5]​.

For Spain, the Ministry of the Environment carried out the calculation of the Water Footprint of Spain, its autonomous communities and its hydrological demarcations together with a powerful simulation tool.[6]​.

• - China's water footprint is around 700 cubic meters per year per capita. Only about 7% of China's water footprint comes from outside its own country.

• - Japan has a total water footprint of 1,150 cubic meters per year per capita, around 65% of this footprint comes from outside the country.

• - The US water footprint is 2,500 cubic meters per year per capita.

• - The water footprint of the Spanish population is 2,325 cubic meters per year per capita. Around 36% of this water footprint originates outside of Spain.

Online calculation of water footprint:.

• - For most countries (in English): Individual water footprint calculation Archived July 25, 2011 at the Wayback Machine.

• - For iPhone (in English): WaterAflamed iPhone calculator.

• - 18,000 liters of water are needed to produce 1 kg of beef;

• - 3 920 liters of water to produce 1 kg of chicken;.

• - 3 000 liters of water to produce 1 kg of rice;.

• - 2,700 liters of water to produce 1 cotton t-shirt;

• - 2 000 liters of water to produce 1 kg of paper;.

• - 140 liters of water for a cup of coffee.

• - Virtual water of some products.

• - Water efficiency.

• - Carbon footprint.

• - Ecological footprint.

• - Hügelkultur.

• - Social metabolism.

• - Transfer.

• - Water footprint calculation in Spanish (web archive).

• - EsAgua: Water footprint platform in Spain.

• - Water footprint Consulted on 08/22/2013.

• - Calculate your water footprint Archived April 1, 2015 at the Wayback Machine. (in English) Consulted on 02/17/2012.

• - Water footprint: the new International Standard ISO 14046:2014. The key aspects.

The water footprint necessarily has a temporal dimension and a spatial dimension. It must be calculated with data collected in a specific period of time (usually the data used is annual) and in a perfectly delimited geographic location (such as an industrial plant, a river basin, or a region). The water footprint is a geographically explicit indicator, showing not only volumes of water use and pollution, but also locations.[4]​ However, the water footprint does not provide information on how the water consumed positively or negatively affects local water resources, ecosystems and livelihoods.

Direct consumption for the manufacture of a product includes the water used and/or contaminated during the manufacturing process and the water incorporated into the product itself as an ingredient. For its part, indirect consumption corresponds to all the water necessary to produce the different raw materials used in the process (supply chain products).

The water footprint can also be expressed in colors, depending on the type of water considered:

• - Green water footprint: related to the rainwater incorporated into the product.

• - Blue water footprint: related to the consumptive use of evaporated freshwater (surface or underground).

• - Gray water footprint: related to the quality of the water and its possible contamination due to discharges.

The International Standard ISO 14046:2014 defines “Water footprint assessment: compilation and evaluation of inputs, outputs and potential environmental impacts related to the water used or affected by a product, process or organization” and presents a method based on Life Cycle Analysis (LCA) defined by the International Standard ISO 14044.

The water footprint or water footprint as opposed to virtual water, and the Water Footprint Network classifies water sources, that is, it distinguishes between three components: blue water, green water and gray water. This classification, especially gray water, has suffered criticism and is not contemplated in the International Standard ISO 14046:2014. The blue water footprint is the volume of fresh water consumed from the planet's water resources (surface and groundwater). The green water footprint is the volume of water evaporated from the planet's water resources (rainwater stored in the soil as moisture). The gray water footprint is the volume of contaminated water that is associated with the production of goods and services. The latter can be estimated as the volume of water that is required to dilute contaminants to the point that water quality is maintained at or above agreed water quality standards. The units in which these indicators work depend on the type of sector for which the water footprint is measured. Thus, for example, the water footprint of a meat product On the other hand, the water footprint of an individual can be measured in [m/year], representing the amount of water consumed over time. This indicator can support efficient improvements in water management and be a good support for raising awareness about our water consumption.

The Netherlands and Spain have shown great progress in the practical development of the water footprint.

To calculate the Footprint of a country, whether water, carbon or ecological, Input-Output analysis is widely used since it is of great help regarding the Life Cycle of Products at a macro level.[5]​.

For Spain, the Ministry of the Environment carried out the calculation of the Water Footprint of Spain, its autonomous communities and its hydrological demarcations together with a powerful simulation tool.[6]​.

• - China's water footprint is around 700 cubic meters per year per capita. Only about 7% of China's water footprint comes from outside its own country.

• - Japan has a total water footprint of 1,150 cubic meters per year per capita, around 65% of this footprint comes from outside the country.

• - The US water footprint is 2,500 cubic meters per year per capita.

• - The water footprint of the Spanish population is 2,325 cubic meters per year per capita. Around 36% of this water footprint originates outside of Spain.

Online calculation of water footprint:.

• - For most countries (in English): Individual water footprint calculation Archived July 25, 2011 at the Wayback Machine.

• - For iPhone (in English): WaterAflamed iPhone calculator.

• - 18,000 liters of water are needed to produce 1 kg of beef;

• - 3 920 liters of water to produce 1 kg of chicken;.

• - 3 000 liters of water to produce 1 kg of rice;.

• - 2,700 liters of water to produce 1 cotton t-shirt;

• - 2 000 liters of water to produce 1 kg of paper;.

• - 140 liters of water for a cup of coffee.

• - Virtual water of some products.

• - Water efficiency.

• - Carbon footprint.

• - Ecological footprint.

• - Hügelkultur.

• - Social metabolism.

• - Transfer.

• - Water footprint calculation in Spanish (web archive).

• - EsAgua: Water footprint platform in Spain.

• - Water footprint Consulted on 08/22/2013.

• - Calculate your water footprint Archived April 1, 2015 at the Wayback Machine. (in English) Consulted on 02/17/2012.

• - Water footprint: the new International Standard ISO 14046:2014. The key aspects.