Our Water Footprint


I see water everywhere, embedded into everything. This concept of virtual, or embedded, water is one I learned from my friend and colleague Tom Kostigen. The co-author of the New York Times bestseller The Green Book, Tom first explained the concept of virtual water in his 2008 Discovery magazine article, “Everything You Know About Water Conservation is Wrong.”

At the time, the concept did not hold much interest for me. I was more concerned with the water I could see than the virtual water it took to make things. But Tom’s latest book, The Green Blue Book, makes clear that virtual water must be a priority. The book details tips for water conservation in our daily lives by revealing the water that is visible (in, say, a dripping tap) and the water that is embedded (the water it takes to make the tap itself). By understanding that a chicken requires about 468 gallons of water to process while an egg contains about 23 gallons of virtual water, we can start to make smarter, systemic decisions about how to conserve our most precious resource.

watertapOur water crisis is local and global. A 2003 report from the United States General Accountability Office predicted 36 states would grapple with water scarcity by 2013. According to Circle of Blue, 18 states expect local water shortages and 16 states expect regional water shortages over the next decade. During a time when one in six people in the world does not have access to enough safe drinking water, and 45 of our 50 United States report “water stress” conditions, we have the opportunity to use less and do better.

I interviewed Tom, asking him to explain our global water challenges and suggest what we can do in our homes every day to improve these scary conditions.


Simran: Tom, you’ve written about the use and abuse of our natural resources for a long time. What prompted you to focus your attention on water?

Tom: Well, after my last book, You Are Here, where I went all around the world to figure out what we do in our daily lives and how that affects people, places, and things in the most disparate of places, I figured out that the one running theme was water. It was on everyone’s mind and really evident and apparent every place I went just how crucial the water issue is, and by that I mean shortages and pollutions. So it really is one of the natural resources that we need to be most concerned about.

Simran: One of the things you describe in the book is the amount of water that we actually have available to us. Can you talk a little bit about that and why conservation and cleanliness of water are so important for all of us to focus on?

Tom: About two-thirds of the world’s population will experience some type of water shortage by 2025. We’re seeing that because of melting of glaciers, and all sorts of run-offs where water gets put into the oceans and it’s not recoverable. Here in the United States, about 36 states will experience some types of droughts within the next five years. We’re seeing it in the middle of the country, where the Ogallala Aquifer is drying out — the Great Plains aquifer. Texas is now the driest state in the region — people don’t have enough water for their cattle. Arizona is an arid state. In California we’re rationing water. So real, real problems and crises afoot.

Simran: In your latest book you say, “The average person needs about 13 gallons of water per day to drink, wash, and eat” but that Americans use almost 10 times that amount. That’s not surprising considering a standard toilet uses about four to six gallons of water per flush and an average shower uses about 20 gallons of water, which is possibly 25 gallons of water used before we even make it to breakfast. It seems like the system is created in a way that we are going to use extreme amounts of water and not really be able to reduce down to 13 gallons, like you mention is what the average person needs. How can we get there?

Tom: It comes through starting to take those shorter showers, it comes to making better and more informed choices. Also, it really comes down to luxury and consumption, like a lot of things. The better off you are, the more water that you’ll likely use, for your now-bigger home and your lawn, the more clothes that you can afford, and the car that you have, and the more travel you partake in. All of these things equate in more strains on our natural resources. So how can we start to be a little bit more simplified in the water that we use? That comes down to literally turning off the tap. People often forget that 50 percent of the water that’s used in the United States goes toward creating electricity. So turning off the lights when you leave a room not only saves the energy that’s equated with that, but it also saves the water that’s used to create that energy.

Simran: What are the most surprising high-consumption activities?

Tom: Seventy percent of all the water that goes to most residences is for watering lawns — so purely an aesthetic thing. Also agriculture is one of the biggest uses of water. So it’s surprising to find out exactly which fruits and vegetables and meats actually use the most amounts of water. And often, we use a lot of things out of season, so we end up importing them from far, far away, and that of course means transportation, it means more energy, it means more water, and it also means storage. We end up storing things that are out of season, and that means some type of cooling process, and that means more water use. So it’s really about getting a little more in tune with nature and its seasons and trying to get things that are fresh and healthier for us, and then just being a little more in touch with the things that we use in our lives and how much water they do use. Just being aware of how much water you use throughout your home.

Simran: Tell us one thing that you would want everyone to walk away with. What would be the most impactful step that people could take moving forward?

Tom: Swap out a piece of meat for vegetables. Swap a hamburger for a salad. That’s a huge, huge savings right there — about 600 to 750 gallons, depending on the size of the burger. It’s so low on the food chain with vegetables. You’re using far less water than you would for any type of meat. And that’s a wake-up call for people. Most people don’t think about how much water is in their hamburger or in their salad. When you start to think about eating lower on the food chain, it does have a huge impact on water. Because as we talked about, agriculture is the biggest user of water in the world, as a sector. So really if you want to go after the most impactful thing, that’s it. Thinking about how much water for your lawn, thinking about water for your plants — all those things have a huge, huge impact, but the number one thing is agriculture. So we have to think about our diets, to really wage any type of meaningful effect on the water supply.


Look, I don’t want to get preachy, but there is something very troublesome about the fact that the average American uses about 150 gallons of water per day, while the average European uses about 66 gallons, and the more than 1 billion people who don’t have adequate access to water use less than 5 gallons per day.

Be mindful,



Photo from Circle of Blue.