It’s time to get to grips with your water footprint

October 07, 2015

It is essential for businesses to measure the ‘virtual water’ embedded in their products, writes Tom Worley – especially when the lives of the world’s most vulnerable are at stake.


Fresh water is the most important resource we have. It is essential for life, a fact emphasised by the UN’s new Sustainable Development Goals (SDGs), which include the goal of “ensuring availability and sustainable management of water and sanitation for all”.

So how much water will you use today? Let’s make a few quick assumptions about what we (in water-rich countries) do on a typical day: have a 5-10 minute shower (50-100L), brush your teeth twice (5L), flush the toilet several times (50L), wash your hands too (10L), cook dinner  and clean up (15L), put on the dishwasher (40L), put on a load of washing (100L) and have several glasses of water/tea/coffee during the day (3L). All up this could add to just over 300L.

What do you do if you want to reduce the amount of water you use? Simple right – take shorter showers, turn off the tap when you clean your teeth, wait to put washing on until you have a full load ready to go, and so on. Do all this and you might get your water use closer to 200L for the day.

However, this is actually only a fraction of the water you require every day. Water is embedded in everything we use, everything we wear and everything we eat. And a lot of it! Water is required as an input at every stage along the value chain of an item, from growing raw agricultural products, to absorbing pollutants, to its use in manufacturing and processing, packaging and transport. This embedded water is known as Virtual Water.

Taking food as an example, the average virtual water requirements are astounding. A single cup of coffee takes 132 litres of water to produce, while a kilo of potatoes takes 287 litres. 1kg of apples = 822L, 1kg of pasta = 1849L, 1kg of chicken = 4,325L, 1kg of beef = 15,415L and 1kg of chocolate requires an incredible 17,196 litres of water.

These figures show just how much of an impact our lifestyle choices have on our personal water requirements, and how much these impacts are externalised. This fact was emphasised and recognised at the recent World Water Week in Stockholm, where ‘going vegan’ was voted as the best idea for saving water.

This is not to say that the only way of solving the world’s water problems is for everyone to stop eating meat or chocolate, but it shows that the choices we make as consumers have the ability to change the demand we place on key resources, thereby limiting our environmental and social impact.

Understanding local impact

Production by business (and subsequent purchasing by consumers) in one part of the world will have an indirect but potentially significant impact on water resources in another part of the world. This is of particular importance to developing nations, whose economies are much more reliant on agricultural output than developed countries, and many of which also face water shortages.

A greater understanding of the water required to produce a certain product or crop in a particular location, coupled with knowledge of sustainable local water availability, will allow greater efficiency in production, particularly around food and will help to achieve SDG #2 on ending hunger and achieving food security.

In order to sustainably manage our production and consumption impacts (as per SDG #12), we need to measure these impacts and understand the associated risks. It is under this idea that the Water Footprint assessment methodology was developed, in order to not only measure total water use, but also the impact on local water resources in terms of green (rain water), blue (extracted fresh water) and grey (fresh water required to assimilate pollutants) water.

Making the case to consumers

There are several great examples of high-profile companies who have undertaken water footprint assessments across their value chain, such as SABMiller, Unilever, Nike and H&M. Organisations such as the Water Footprint Network have led the way in methodology development. But water footprinting it is not yet widespread or well-communicated to consumers.

As climate change affects the resilience and availability of water resources across the world, it is going to become crucial for organisations, from all sectors, to work in partnership with members of their own value chains to measure their water footprint, understand what points face the greatest risks and importantly where these risks are located. This will be crucial in looking forward to achieving several of the SDGs. The task is then to find a way to communicate this effectively to customers, so that they can better understand and manage their own impacts.


Tom Worley is a Consultant at Corporate Citizenship.