Water footprint
Introduction
A water footprint is a measure of the amount of water used to produce each of the goods and services we use. It can be measured for a single process, such as growing rice, for a product, such as a pair of jeans, for the fuel we put in our car, or for an entire multi-national company. The water footprint can also tell us how much water is being consumed by a particular country – or globally – in a specific river basin or from an aquifer.
Understanding Water Footprint
The concept of a water footprint was first introduced in 2002 by Professor Arjen Y. Hoekstra from the University of Twente, the Netherlands, and it has since been developed into a comprehensive research field. The water footprint is a multidimensional indicator, showing water consumption volumes by source and polluted volumes by type of pollution. It refers to the volumes of water consumption and pollution that are 'behind' your daily consumption.
Components of Water Footprint
The water footprint consists of three components:
- Green Water Footprint: This is the volume of rainwater consumed during the production process. This is particularly relevant for agricultural, horticultural and forestry products.
- Blue Water Footprint: This refers to the volume of surface and groundwater consumed as a result of the production of a good or service. Irrigation can increase yields significantly and it can make crops less dependent on rainfall, providing a buffer against drought.
- Grey Water Footprint: This is an indicator of the degree of freshwater pollution and is defined as the volume of freshwater that is required to assimilate the load of pollutants based on existing ambient water quality standards.
Calculation of Water Footprint
The calculation of a water footprint involves a detailed water use assessment that quantifies the amount of water used in the production of goods and services. This can be calculated at an individual, community, or business level. The water footprint assessment includes both direct and indirect water use.
Importance of Water Footprint
Understanding the water footprint of individuals, businesses, or nations can help to show how water is allocated and where it is being used inefficiently. It can also help to identify areas where there are opportunities for water savings, and it can highlight the impacts of consumption patterns on local water resources.
Water Footprint in Agriculture
Agriculture is by far the largest user of the world’s freshwater resources, consuming 70% of all surface water supplies. However, some agricultural practices can dramatically increase the water footprint of the crop grown.
Water Footprint in Industry
The water footprint of a business, also known as corporate water footprint, is defined as the total volume of freshwater that is used directly or indirectly to run and support a business. The water footprint of a business consists of water used for producing, manufacturing and supporting activities.
Reducing Water Footprint
There are several ways to reduce the water footprint of individuals, communities, and businesses. These include water-saving measures at home, changes in diet, and improved water efficiency in industrial processes.