Water Footprint — The Importance of Virtual Water
Water is one of our planet’s most precious resources. It is ubiquitous: we drink it, wash with it, swim in it, and sail on it. We also use it to produce things like food, paper, and cotton clothing, among others. But what is virtual water? Is it invisible? Sort of. But it is equally — if not more — omnipresent. Virtual water, or the water footprint, is an indicator of water usage that looks at both direct and indirect water use of a consumer or producer. The water footprint of an individual, community or business is defined as the total volume of fresh water used to produce the goods and services, consumed by the individual /community or produced by business.
We don’t realize it as we sit down to a meal, but most crops require huge volumes of water to grow: 65 gallons to grow a pound of potatoes; 650 gallons for a pound of rice. How about your cup of coffee? It takes far more than one 10 ounces to make it. Thirty-seven gallons of water were used from the time the bean was planted to the moment it hits your cup at Starbucks. That includes growing, harvesting, packaging, and shipping it. And that’s without adding any milk (which took another 67 gallons of water to produce).
At a national level, it becomes more complicated. Here’s the formula:
Domestic water resources used
virtual water exports
virtual water imports
equals: the water footprint of a nation
For further information: http://blog.cleantechies.com/2011/08/11/water-footprint-%E2%80%93-the-importance-of-virtual-water%E2%80%99/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+cleantechies+%28CleanTechies+Blog%29&utm_content=Google+Reader