These scenarios should help to illustrate different thinking around how consumption and production decisions of industries and households impact water resources.
Scenario 1: Your weekly shopping
A careful examination of the contents of your shopping basket shows that water is required in making each product.
The most obvious connections to water use are the fruit, vegetables, milk which all require water embodied in the soil and from rainfall. However, things might be slightly more complicated than this.
First these types of products may need to be packaged and distributed and this may require additional water use. Second, some of these products may have come long distances. Taking the case of Wales, milk and potatoes might be locally produced, and benefit from the relatively abundant rainfall in the west of the country.
However, products like tomatoes (according to the season) and coffee are often imported and use up water resources in locations many thousands of miles away. Indeed these products may be produced in areas that suffer from more water stress than would be the case in Wales.
Water used in the production of these goods may leave less water for human needs or cause depreciation of a wide range of ecosystem services provided by water bodies and water catchments. Then while our households consume water directly in the home, our purchases of goods and services also entail use of water resources at home and overseas.
In summary our water ‘footprint’ embraces far more than our direct consumption in the home and at work, and needs to consider ‘indirect’ use of water that occurs because of our consumption patterns, and water embodied in products imported (i.e. embedded in our trade).
Scenario 2: Your new car
One might not immediately connect the production of a new car to water consumption. Indeed one might argue that water use in car plants might largely be made up of on-site consumption of water by employees of the industry.
However, there are some industries that might not use high volumes of water directly in their production processes, but they might require goods and services in their processes that do require large amounts of water.
Then the car assembly plant will require products from industries such as the chemicals, plastics, rubber and metal industries that might be larger users of water, and perhaps more importantly might be responsible for higher levels of pollution of water bodies.
From the above simple scenarios a number of conclusions can be made:
First, only a partial appreciation of freshwater use connected to human consumption activities is gained from an approach that focuses on the direct water use of a household, or an industry process.
Second, we need to think beyond simple withdrawal of freshwater from water bodies, and think more in terms of how human consumption connects to the overall appropriation of freshwater resources.
In the next step, we will be exploring the water footprint concept a little further. We’ll also provide you with additional examples if you want to read more on this subject.
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