State of the Planet

News from the Columbia Climate School

Water Footprinting

Last week, the Wall Street Journal published an article about how companies are starting to calculate their “water footprint” as well as their carbon footprint to institute more water friendly policies.

Commercial companies have discovered that it takes “20 gallons of water to make a pint of beer, as much as 132 gallons of water to make a 2-liter bottle of soda, and about 500 gallons … to make a pair of Levi’s stonewashed jeans.”  One company has even determined takes 630 gallons of water to produce a typical hamburger!

The methods of calculating a water footprinting, however, still have yet to be standardized. Some people think that a water footprint should only contain what is actually used in a factory, others think that the water used to grow the ingredients for the supply chains, and occasionally companies even include water used after the product is sold (i.e. for transportation, refrigeration, storage, etc.).  How far should we go down the line though? Should Tide or Gain be expected to consider the water to be used in all loads of laundry?

Another important issue that occurs with water footprinting is that a “water footprint” is not equal in all areas of the country.  While it may take more water to grow a crop in region A, depending on rainfall statistics and water availability, it could be preferable to growing a crop in region B.  For water footprinting to be successful, it needs to be decided what should be included, as well as finding a way to easily compare footprints from different regions.

As water  footprinting begins to gain popularity, more companies are evaluating their water usage – an often changing their policies! Unilever reposted in a 6 year period saving $26 million by decreasing the water use in their factories. And they aren’t stopping there – they have a whole plan to make the company even more sustainable.  As more companies realize the amount of fresh water used in certain practices, they will see they can not only help protect freshwater, but they can also save money!

So  in the morning when you drink a pint of beer (20 gallons), a 2-liter of soda (132 gallons), or put on a cotton t-shirt (700 gallons) and jeans (400 gallons), think about it.

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Meaghan Daly
Meaghan Daly
15 years ago

Thanks for updating us on this, Jennifer! Water footprinting is likely to be an increasingly valuable tool, as it’s a good way to analyze local water shortages within a globalized economic context.

This is especially true when you start to consider that many of the countries that produce and export goods are often those that have the least regulation of water resources. When we use water footprints, it’s easier to see how consumption in one place has a direct impact on water stress elsewhere.

I hope to see water footprinting become a common practice in the future!

Dan Stellar
15 years ago

Water footprinting, or the closely related isue of “virtual water” is a very interesting issue. As companies focus more strongly on sustainability it is bound to get more attention. However, as this post rightly points out, a host of important and controversial issues need to be sorted out to make water footpriting calculations meaningful. In addition to issues of supply chain and location, another important issue is water quality. If a manufacturer brings 100 gallons of clean water in, and dumps out 100 gallons of even slighly contaminated water, is that still “water-nuetral”? As difficult as carbon footprinting is to track, water footprints raise even more issues. While it’s great the profile of the water issue is being raised, more research needs to be done to standardize procedures, so meaningful comparisions can be made.

Joshua Nelson
15 years ago

An interesting concept to have Tide and Gain take into account the water used in each load. However, the water footprint on its own should take these daily uses into account and whatever amount goes into the products you buy themselves. The connection of the the product and its consumer-use-associated water should be separated, because while we all use laundry soap some of us have water efficient washers and some of us don’t.

Mother Jones magazine recently wrote an interesting article on the pitfalls and triumphs of water footprinting. I would recommend it!