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Water footprint describes total water use
A water footprint illustrates the water intensity of our lifestyles. The greater the water footprint, the larger the volume of water used. The footprint includes all water use: the water you run from the tap and the so-called virtual water, or hidden water, which refers to all water that is used to produce goods, such as the water used for the production of raw materials, intermediate products, energy and services.
Direct water use accounts for less than five per cent of the Finnish consumer’s average water footprint, while the remainder is virtual water contained in the products and services we buy, whether they were produced in Finland or abroad. Water abstraction for human needs creates an environmental problem if the abstraction rate exceeds the renewal rate of the water resources. This can be the case in water-scarce areas and may result, for instance, in continual lowering of groundwater elevation.
In addition to the volume, the type of water used and the purposes it is used for play a key role. Do we use finite groundwater or other fresh water resources, or perhaps sea water or rain water, and what is the impact of wastewaters in the water bodies where the abstracted water is returned after use. The largest volumes of water are used for cooling purposes, especially in energy production and manufacturing industries, but this water is returned to the sea or lake as clean as it was when it was first pumped out. In contrast, harmful wastewater is created when water is abstracted for sanitary purposes, washing or industrial processes. Such aspects are also considered in water footprint calculations, and they are expressed as different colours of the footprint.
A water footprint can be calculated for many types of users
A water footprint can be calculated for a product, a private citizen or even for an entire nation. To estimate your personal water footprint, you may consider using the Finnish Environment Institute’s Water footprint calculator.
A footprint can also be calculated for an individual company or a specific industry. Agriculture is the largest water consumer on a global scale, whereas forest industry is the largest water user of all sectors in Finland. However, even larger quantities of water are used in energy production for cooling purposes. In hydropower plants, great masses of river water flows through turbines, but this water is usually not counted into the water footprint..
A water footprint can also be calculated for products and product groups. However, the footprint of an individual product depends to a great extent on where and how it was produced, and what adverse effects the production caused on local water resources and water bodies. One third of Finland’s entire water footprint consists of virtual water contained in imported products.
Things to bear in mind when assessing water footprints
Availability of water in different regions. By and large, we have enough water for all uses in Finland, but imported products may have been produced in regions struggling with a scarcity of water. Shortages of good-quality water may also occur locally in Finland.
Different sources of water. The choices between using rainwater, surface water or groundwater and the possible paucity of these water resources affect the depletion of water reserves.
Transport distances of water.Long transport distances exacerbate the costs and harms of water consumption.
Modes of water use. Not all types of water use put the same pressure on water resources. Surface water used for cooling is returned chemically unchanged to the water body where it came from whereas water contained in a product or evaporating during a manufacturing process is considered as “consumed water” (to differentiate from used water).
Contamination of water. Typically, water used in production is returned to the environment as wastewater which may contain harmful contaminants. The extent of contamination depends on the quality of the initial wastewater and the efficacy of wastewater treatment for different pollutants.
Water footprint colours
Click on the numbers to see what each colour represents.
Blue water footprint
Blue water footprint
The blue water footprint refers to water abstracted from groundwater deposits, lakes, rivers, artificial ponds or the sea. If the rate of water abstraction is greater than the rate of regeneration, the water reserves will become depleted before long. Significantly depleted groundwater resources are a course for concern in many agricultural regions globally, and surface water resources are also overused in some regions. The Aral Sea, for example, has dried up because the waters in the rivers discharging into it are used for irrigation. Finnish consumers are also responsible for the blue water consumed to produce imported products used in Finland. Products bought by Finnish consumers may exacerbate water shortages in other regions of the world.
Grey water footprint
Grey water footprint
The grey water footprint describes the negative impact of wastewaters discharged into water bodies. The size of the grey water footprint, in other words the harms caused by the influx of wastewater, depend on both local conditions and the substances contained in the wastewater. For example, persistent organic pollutants create a much larger grey water footprint in proportion to their emission amounts than nutrients that cause eutrophication. The harms are also exacerbated if the wastewater influx is large in proportion to the size and flow rate of the lake or river in which it is discharged, or if this water body is particularly sensitive to pollution. Emissions that seep into the soil may contaminate groundwaters across a large area.
Green water footprint
Green water footprint
The green water footprint refers to rainwater transpired by cultivated plants. Farming in which crops are mainly irrigated by rain, or collected rainwater, has a particularly large green water footprint. The green water footprint of forestry is also big, and this concept has consequently been criticised in such countries as Finland where the needs of crops and forests are mostly met with rainwater. In drier areas, it is more vital to use even rainwater sparingly to avoid resorting to other sources of water. This means, for instance, that the water retention capacity of arable fields should be looked after and that water consumption should be taken into account when choosing crops and farming methods.
Water-smart circular economy
Water can be seen as part of circular economy. The objective of circular economy is to use the Earth’s finite natural resources smartly, avoiding losses and ensuring that substances and energy remain in use for as long as possible, rather than just flowing through the production and consumption chain.
In water-smart circular economy water is used efficiently and losses are minimised. Any substances dissolved in the water and energy bound to it are recovered and reused, as is the water itself. The use of reclaimed water requires careful risk assessment and management, however, to ensure that any impurities that may remain in it will not harm the environment or human health.
Ways of reducing the water footprint
Click on the numbers to see how each group can make a difference.
Individual citizens
Individual citizens
More than 75% of Finnish people’s blue water footprint and almost an equally large share of their grey water footprint comes from imported products. A responsible consumer strives to avoid imported goods whose production uses up a great deal of water and generates harmful emissions. Agricultural products are the key in this respect, as they account for four fifths of the blue and grey water footprint of imported products. In particular, foods produced in regions where the water situation is critical should be avoided, including parts of the Middle East and some regions in Africa and Asia. Agricultural production is also depleting water resources in drought-stricken California and parts of Spain.
Companies and industries
Companies and industries
In Finland, companies’ and municipalities’ efforts to reduce their water footprint have mainly focused on grey waters, in other words wastewater treatment, and great strides have indeed been achieved in this area in the last 50 years. However, there is still plenty of scope for improvement, for example in removing different harmful substances from wastewaters. The efficiency of water use should also be improved further and losses should be reduced, and water responsibility should be extended to cover the entire value chain, also outside Finland’s borders. This means that a company or municipality assumes responsibility for its water use and wastewaters at all stages and manages the water risks associated with its activities. In agriculture, nutrient loading accounts for a large share of the water footprint, which is why agriculture has the largest grey water footprint of all Finnish industries. Above all, water responsibility in Finnish agriculture means reducing these emissions.
The central government and policy-makers
The central government and policy-makers
Reducing Finland’s water footprint is a common goal, and each stakeholder has its own tasks and responsibilities in achieving it. It is up to the central government and policy-makers to guide and support citizens, companies and industries in their attempts to achieve smarter water use and water responsibility. At the general level, this means raising awareness of water issues and promoting water-smart circular economy as well as taking this perspective into account in development projects, legislation and, for instance, agricultural, industrial and trade policy. Practical education and support measures include offering citizens and companies tools for calculating their water footprint, comparing products and production methods and enhancing their water responsibility. The central government must naturally also take care of reducing its own water footprint.