A nation of spongers?

It may seem unlikely given our much-discussed damp climate, but the UK is in fact one of the biggest importers of water, per capita, in the world. Our sponge-like tendency is not just due to our thirst for French mineral water. Water is ‘embodied’ in almost every single thing that we import: food, energy, and products alike.

The idea of water being embodied in products is not new, the concept of ‘virtual water’ having first been introduced in 1993 by Professor John Anthony Allan of the School of Oriental and African Studies. The fundamental notion is that any water used during the manufacture of a product can be understood to be incorporated or ‘embodied’ within it. So, as you may have heard, around 140 litres (about half a bath full) of water is embodied in one 125ml coffee, over 1,000 times the end volume. The majority is used in actually growing the coffee plant, and more again used in transport and processing. Although some of this water will come from the country in which the end product is consumed, much of it will have been used (and will therefore no longer be available for anything else) in a different part of the world.

International water weigh

A massive amount of water from rivers, rainfall, aquifers and lakes around the world – much of it from countries that rely more on the primary economy than we do – is being used to support lifestyles here in the UK. We consume 63.6Gm³ of foreign virtual water every year, the sixth highest total in the world. Picturing a billion cubic litres is tricky, but each Gm³ is a cube of water measuring kilometre in each dimension. 63.6Gm³ equates to roughly 8.5 Loch Nesses or 42,000 Millennium Stadia-full. It means that each of us in the UK is using nearly 3 tonnes per day. It is nearly 20 times more than all of the drinking water consumed in the UK (which also includes all of our washing and cooking).

Those are some large numbers, but it is estimated that there are 93,113Gm³ of fresh water just in the world’s rivers and lakes – and of course, more falling out of the sky each day.  This is where things get difficult:  how damaging exactly is 63.6Gm³ of imported virtual water? We just don’t know because although we can calculate the figure based on the amount of water needed to produce goods, we don’t know where, when and how it was sourced. Irrigating crops from a river with very limited summer flows will pose a much greater threat to water availability than will irrigation from a plentiful source.

Does this matter? I believe so, but the complexity of the problem doesn’t mean that we can just ignore it. Perhaps it would be fine to do so if there was sufficient water in all the regions of the world, but this is not the case, and with global climates becoming more erratic and populations rising, the number and size of regions experiencing water stress has been argued to be increasing; witness the tension over fresh water in Central Asia as just one example. Much of the water we import may come from regions and sources that can currently sustain this use, but this is certainly not the case for all of it. A significant amount comes from regions facing ever reducing water availability, where the virtual water we are importing is needed by people and the ecosystems they are part of.

Getting into hot water

This raises two questions here in the UK:

1. Is it morally acceptable to appropriate so much from regions in which people are struggling for enough water to live and the abstraction of water is damaging ecological sustainability?
2. If water is becoming scarcer globally, is it prudent to be so heavily dependent on water from regions that are likely to experience increasing water stress in the near future ?

In these times of economic necessity, moral arguments have less weight than ever when set against financial considerations, so perhaps the first question is one to which, regrettably,  only a small segment of society would answer “no”. However, self interest leavened with only a little enlightenment might be expected to have given the second question much more traction than it currently has.

Bangladesh is a country that many people associate with too much water – flooding being an issue for a large proportion of the population. However, it is facing increasing challenges in finding sufficient drinking water, both in rural areas and in Dhaka. As the rainfall in Bangladesh changes and more water is pumped out of the ground, saline water from the sea is starting to seep into important aquifers. In many places these aquifers are the only sources of potable water for the local people. These challenges will not go away, and the impacts will be felt here in the UK, too.

The outcry following the recent collapse of a clothes factory in Dhaka was a reminder that much of our cheap high-street clothing is made in Bangladesh. Clothing requires a vast amount of water to manufacture – primarily in the irrigation of cotton crops— and this is water that Bangladeshi people and their government may eventually decide that they need for themselves rather than to produce chinos for Westerners. It may not be a critical issue on its own, but the compounded impact of all such issues will be very hard to ignore. We may survive without bargain chinos, but where would we be without our grain and pulse imports from regions heavily reliant on irrigation?

Once we start asking these questions, it is hard to ignore the issues. How exposed are we to the impending water crises in Asian regions where the ‘Green Revolution’ is leading to over-abstraction from aquifers, with no clear way of replacing this source once it expires? What impact will the eventual failure of the aquifers in the American Mid-West have on global food prices and the availability of imports? In general, how prepared are we for future water scarcity, and what can we do about it?

Treading water – the UK has yet to get serious about water footprinting. Image by Stoppe, via Wikimedia Commons.

Best foot forward

The concept of the carbon footprint has proven successful in capturing the public imagination and in raising awareness of the carbon impacts of our lifestyles. It has understandably inspired those with an interest in water to push the idea of a water footprint, but the concepts are different in important ways. Whereas CO₂ has much the same effect wherever it is produced, water’s impact depends very much upon where and how it is used, making meaningful footprinting rather more difficult. Yet in a globalised world where we export our problems, water footprinting may at least provide us with the conceptual equipment to understand the potential global impacts of our actions.

It is becoming ever more urgent that we act, if not from altruism, then at least that we have prepared ourselves for an inevitable ‘low water’ future. Some of the actions we can take are quite simple, and would be motivated by the wider use of the water footprint concept:

1. Consume and waste less: if we waste less food, packaging etc. then we reduce our reliance on increasingly scarce water.
2. Promote techniques that require less water to do the same jobs.
3. Protect land (in the UK and overseas) that is vital for aquifer recharge (as Nestlé-owned Perrier and Vittel have done to secure the springs from which they obtain their water), thereby maintaining water availability for the future.

We cannot continue to assume that we will be able to remain global spongers, soaking up the water resources of less well-off nations indefinitely. Many water-stressed regions are also growing economic powers that may not always be inclined to effectively export vast amounts of their precious water. It is only the inequality in international trade that enables us to consume so much virtual water as we do now.

In this context, the massive waste that we witness in the UK of food, energy and consumer products appears even more unsustainable. The water embodied in this waste will not be so cheap, or even available, for ever and we need to understand our water footprint properly if we are to learn to tread more lightly. The need to adapt is urgent, and our choices are either to take measured steps now, or be shocked into emergency action once water crises begin to make themselves felt around the world.