The growing scarcity of water is not just a problem for sub-Saharan Africa, it’s jeopardising the future of food production all over the world. Kelly Parsons asks what can be done

What's the water footprint of a kilogram of rice? Fifty litres? A hundred? How about a kilogram of beef? Five hundred litres? A thousand? Would you be surprised to learn the answers were 3,000 and 16,000 litres respectively? Admit it, you would.

"Global drying" may be the topic du jour at high-level conferences (in January, Nestlé chairman, Peter Brabeck-Letmathe backed a new initiative aiming to secure the future of water at the World Economic Forum in Davos), but few of us would have a clue that rice and beef are among the world's thirstiest foods or that a single cup of coffee takes 140 litres of water to produce and a litre of milk 1,000.

And we're certainly not doing enough to tackle the issue. Almost two thirds of businesses polled in a survey of decision makers by UK government-funded sustainability programme Envirowise last year said they didn't monitor water use at all and 85% didn't have any reduction targets in place.

Considering agriculture is responsible for 70% of global water use and that, by 2025, 1.8 billion people will be living in water-scarce areas, that's a pretty daming indictment.

A few companies are starting to walk the walk, however, and with such purpose that some experts predict water footprinting will soon overtake carbon footprinting in significance if the industry can get its head around it, that is.

As with its carbon cousin, establishing the parameters for measurement is difficult. "If you think carbon footprinting is complex, welcome to the world of water footprinting," says Claus Conzelmann, vice president of safety, health and environmental sustainability at Nestlé.

That's why most are starting with the simpler and arguably more meaningful step of measuring and reducing their water usage. Last January, the Food and Drink Federation and Envirowise launched the Federation House Commitment, an industry-wide target to reduce water use by 20% by 2020.

The initiative now has 37 signatories, among them Nestlé, Coca-Cola and Premier Foods, and it appears to be working just. The joint water usage of signatories, aggregated and reported on a collective basis, fell 1.4% between 2007 and 2008 (a further progress review is due at the end of this month).

Many of the commitment's signatories are 'early adopters' of good water management, working closely with NGOs and doing the rounds at water conferences. Nestlé has become a bit of a poster boy, reducing water use in its own operations by 30% over the past decade. The company is helping suppliers such as vine-ripened tomato growers in the Parma region of Italy adopt new water management technology to produce 'more crop per drop'.

Coca-Cola has similarly ambitious aspirations. It runs 250 community water programmes around the world and aims to become completely water-neutral in its own operations.

And it's not just the manufacturing giants that are getting in on the act. Innocent (which coincidentally Coke has a £30m stake in) has been developing its water strategy for several years, and even the East Midlands Development Agency is working on a number of water-based projects with regional food businesses.

"Water is at the top of our agenda," says Michael Stubbs, manager of EMDA's Rural Development Programme for England. "For veg & salad growers in Lincolnshire, it's becoming as important as energy security. They also see it as a point of difference if they can go to Tesco and demonstrate their security of water supply."

Projects in the county include improving winter storage reservoirs, collecting roof rainwater for irrigation, cattle drinking and washing, and harvesting 'waste' water from milk and potato peelings, cleaning it up and using it for washing and ­processing. But therein lies the problem. Even companies that are aware of the issues are unclear as to what they should be doing about it and as a result a consensus has not yet been reached on the best way forward.

"Unlike, for example, the forestry sector, where the Forestry Stewardship Council guidelines are well established, we're still at the VHS versus Betamax stage with water," says Dave Tickner of WWF, which is working with several other NGOs on the Alliance for Water Stewardship.

Comparisons with carbon and the ongoing confusion surrounding the measurement of it are inevitable, but water stress is far more complex to monitor. 'Virtual' water can be carried thousands of miles from drought-ridden areas embedded in products, so the impact of high water consumption in one country is often felt most on the other side of the world.

The Water Footprint Network has devised a footprinting equation to assess and to some extent address this. WFN defines a water footprint as the total volume of fresh water used to produce the goods and services consumed by the individual or community or produced by the business.

But this method has its limits, says Nestlé's Conzelmann. "We were a founding member of the WFN and there's no doubt it's a useful tool because it forces companies to look at savings across their entire value chain. But it only provides part of the story, because it counts litres of water but not the environmental impact."

It also fails to take into account the amount of water embedded in a product, which is a separate issue in itself. Jacob Tompkins, managing director of NGO Waterwise, warns companies against adopting an overly narrow focus on footprinting, arguing it can distract from what should be the real task in hand improving efficiency.

"On the back of the carbon footprinting trend, a whole industry has grown up around analysing and counting water, and it has created a monster, measuring every drop of water that goes into a tin of beans." Businesses should be looking directly at where they operate and the water they are taking out, he says. "They could save 10% to 20% by putting aside a couple of days of management time to do a simple water audit and pinpoint where water is wasted, before paying a consultant to come in."

Lauren Orme, sustainable raw materials manager at M&S, couldn't agree more. She says that although the academic community has developed a footprinting methodology, it is still debating how to take that figure and understand the impact. "It could take 10 or 15 years to be resolved, so we need to take action ourselves now, and we've started by engaging our suppliers to understand how their water impact can be reduced," says Orme.

M&S is already working with WWF to map usage in five produce supply chains and is researching a stakeholder approach in Almeria, southern Spain, in conjunction with the Food Ethics Council.

Retailers like M&S are beginning to think about what demands they can make on suppliers, says FEC researcher Santiago Ripoll, but they could still be doing more. "Supermarkets, for example, have a lot of quality standards to uphold and ask their suppliers extensive questions about pesticides, size of operation, water quality, yet nothing on water scarcity."

It's a question that they will have to start asking soon. Those that get the answer wrong could score a spectacular own goal if they fail to address the issue, particularly if they're based in a water-scarce region that's on the radar of the environmentalists.

Coca-Cola learnt the hard way back in 2000. In Kerala, southern India, the company was the target of drought-induced community unrest. As a result its local bottler lost its licence to use groundwater.

"We learnt the importance of community engagement," says Lisa Manley, group director of sustainability communications. "At a time of local water shortages in Kerala, the community saw big red trucks with Coca-Cola on rolling out of our bottling plants and assumed we were stealing their water. We now work closely with communities to understand the health of the watershed and explain how we use water."

Other companies, meanwhile, have gone a step further and made tackling the water crisis their entire raison d'être. All the profits generated from sales of One Water bottles, for instance, go to building PlayPump water systems in Africa.

It's not just communities that need to be appeased. Investors, too, expect be kept in the loop. A study on corporate reporting of water risk, published in February by CERES, the US coalition of investors, environmental groups and other public interest organisations, found overall governance and disclosure by 100 companies (including 10 food and drink companies) fell well short of what investors expected.

The Carbon Disclosure Project, a UK non-profit organisation, also has water disclosure in its sights. Last November, it announced an investor water disclosure initiative. This year, it will send questionnaires to 300 of the world's biggest companies in water-heavy sectors, asking them to disclose metrics on water use and wastewater discharge and highlight exposure in their direct operations and supply chain.

The level of scrutiny will only increase as water becomes the 'en vogue' cause and pressure from environmentalists, investors and consumers mounts.

If water footprinting is the best way forward, the industry will need to put its best foot forward soon.

Case study one: Robert Wiseman Dairies
Robert Wiseman Dairies' operation in Bridgwater, Somerset, is acknowledged to be one of the most environmentally advanced dairies in the world. Its technology and systems have enabled the company to reduce overall use of water to 0.57 litres per litre of milk produced, a third of the sector average.

Robert Wiseman has been closely involved in Defra's Milk Road Map, launched in 2008, which commits farms to reduce water by between 5% and 15% per litre of milk by 2010 and big dairies to cut water use by 30% by 2020. It has also set its own target to reduce water use by 20% over the next five years and is set to make a 7.4% reduction in 2010 alone.

"The ever-increasing cost of water coupled with business risk from decreasing supply is a double whammy, so we have invested heavily in facilities to optimise efficiency," says Julie Walker, Wiseman supply chain director. By introducing ever-more efficient technologies at its plants, water reduction is inevitable, she adds.

At Bridgwater, rather than simply being wasted, water used in production is now recycled for vehicle washing, boiler feed, and even irrigating the neighbouring cricket pitch. 

Case study two: SAB Miller
SAB Miller is at the cutting edge of water footprinting.

The company's mapping of water in its beer value chain is an often-cited industry example of the possibilities and limitations of this nascent methodology. Working in conjunction with WWF, the company first applied the concept in 2008 in South Africa, measuring water used in crop cultivation, processing, brewing and bottling and bottle recycling. SAB calculated a footprint of 155 litres for one litre of beer.

The company repeated the exercise a year later in the Czech Republic responsible for producing 20% of the company's overall European beer volume and home to the Pilsner Urquell brand and found a litre of beer only required 45 litres of water.

The difference is down to climate and irrigation factors, and the quantity and source of imported crops. After each study the company held local workshops to discuss the findings and come up with an action plan focusing on the various hotspots of water stress along the value chain.

"How water is used locally can have a very different impact depending on what proportion of the total available resource is being used," says SAB's head of sustainable development Andy Wales.

Quality, quantity and availability: the choppy waters of EU water law
Uncertainty about water risk has not been helped by the legislative framework for businesses.

The European Water Framework Directive came into force in 2000, but implementation overseen by the Environment Agency in the UK is a work in progress. The directive focuses on achieving good status for Europe's water bodies.

Member states are going through the lengthy process of identifying water bodies (seas, lakes and groundwater), assessing the pressures and impacts on them and implementing measures to tackle them. As well as being very complex, the substance of the law has also been criticised.

"The directive doesn't go far enough," says Santiago Ripoll, researcher at the Food Ethics Council, "because it doesn't take into account availability of water." Another problem is a division of opinion among states. Jacob Tompkins, MD of NGO Waterwise, says the EWFD is viewed as a northern European directive by southern states because "it's all about quality of water, whereas in the south they are obsessed with quantity.

"There has already been an EC communication on water scarcity and droughts, and there's talk of a further directive."

There are also indications a legislative clampdown could be on the cards. "In 2011 France will introduce mandatory carbon labelling, which we see as a clear move by lawmakers in this direction," says Nestlé vice president of environmental sustainability, Claus Conzelmann.