The last few years have seen some very bad droughts. In the UK, the drought of 2004-2006 was severe enough to nearly require the shutting down of domestic water in London and the fetching of water from public wells (called standpipes). Australia has been suffering from its own decade long drought with devastating consequences. As a result, water-awareness in both countries has been rising. People are at least dimly aware of ideas for saving water, such as turning off the tap while brushing one's teeth. In Australia there was even a government sponsored advertisement recommending taking showers with someone else. However, as a recent report from the World Wildlife Fund shows, even if we stop showering altogether, we will still be using an unsustainable amount of fresh water.

The WWF report looks beyond the tap water we use, and considers the water needed to make the things we use. For example, when we consider the water use at every stage of the process, 140 litres of water are needed to make a single 125ml cup of espresso coffee, 15,000 litres are needed to make a kilogram of beef and 2,700 litres are needed to make a cotton shirt in Pakistan (see more here). In total, the average resident of the UK uses only about 150 litres of tap water per day, compared to a total of 4,645 litres of water when all sources are included. Even if we switched of all our taps, and never drunk, bathed or washed our clothes, we would only cut water use by 150 litres each, or about 3% of the total.

The implicit water cost of everyday things is known as 'virtual water'. As we can see, most of our water usage is in virtual water and according to the WWF, 62% of the total water use in the UK is virtual water from other countries. In other words, the UK is a massive importer of virtual water in the form of products that require a lot of water to make. What is worse, is that much of this water comes from parts of the world which are far more arid than the UK, contributing to severe and unsustainable environmental degradation.

What can be done about this? I can see two obvious possibilities. Firstly, we could educate people about how much virtual water is in different products, much like education about carbon footprints. We could even extend this to enforced labelling in supermarkets. This would rely on the goodwill of consumers, but at least it is a start. A second way would be for governments to start charging a fair price for water. At the moment, they effectively subsidize water, selling it to citizens for less than its true cost. If they were to increase what they charge (and offer tax-credits to make the whole thing revenue-neutral), then we would no longer have to rely on goodwill -- consumers and producers alike would conserve water in their own interest and to the appropriate degree. This approach is similar to taxing carbon, and shares some of its challenges: particularly the need for international cooperation. Whatever the eventual solution, this is a serious and neglected issue and needs to be addressed promptly.

In the meantime, the easiest way for an individual to conserve water (and thereby reduce your water-footprint) is to move to a vegetarian diet. For someone in the UK, this is enough to reduce your water footprint from 5,000 liters a day to just 2,000 (a saving equivalent to a six hour long shower). Even just minimizing consumption of beef would make a very large difference -- much larger than that of all your tap water usage put together. This might even be the best reason there is to move towards a vegetarian diet.