The most effective way to reduce your water footprint

The most effective way to reduce your water footprint might surprise you. It’s not turning off the faucet when we brush your teeth, or collecting water from our shower to water plants, or even taking fewer showers.

The biggest part of our water footprint is our diet.

And it’s a problem.

Because one of the big issues with the zero waste movement is that we tend to think of zero waste and reducing waste as a very physical thing. We focus so heavily on plastic bags, straws, and the small details. That’s because they’re A) easily visible and B) give you an immediate feel-good moment when you avoid them.

And I think this is the crux of why the zero waste movement is so hyper-focused on the Pinterest-y aspects of zero waste. Because it’s really hard to associate the food on our plate with massive water usage in far away farms. It’s also harder to make changes in something that we truly need to survive, ie. food.

Having said all that, let’s dive into the topic of food and its water footprint.

how can we calculate food’s water footprint?

How can we calculate food's water footprint? - Green Indy

Very basically, a product’s water footprint is measured by three things: blue water, green water, and grey water. The total of those three show the total amount of water needed to produce that item.

What’s blue water?

The surface and ground water needed for a product. Basically, water taken from somewhere else like a reservoir or lake and added to the fields. Large agriculture uses blue water most often – just as any gardener might – but the effects of diverting water on such a large scale can be devastating.

In one particularly horrific example, billionaires exploit workers and the land, all at the same time. “In a land of outrageous poverty, the Resnicks have built a billion-dollar fortune by growing trees with water from an artificial river while the migrant workers who tend the irrigation pumps don’t have access to potable water in their homes.” Read the full article about the nut and fruit growers here or listen to The Dollop episode for even more fascinating background.

What’s green water?

Rainwater and soil moisture. While likely the lowest impact way to grow, a 100% green water system is rare and likely to become rarer as weather patterns become more unpredictable. 

Take California almonds (a water-intensive crop grown in a relatively dry place). Each pound of almonds requires 635 gallons of blue water to only 68 gallons of green water (source). That means that rain plays only a very small role in watering almonds. (And, you know, it may be worth reconsidering your almond milk for a less water-intensive option!)

What’s grey water?

How much clean water is needed to dilute waste water created from chemicals applied to crops, animal waste, etc.

And this waste water concoction can be a huge issue, particularly as massive factory farms face off against increasingly dramatic weather. “When a pig in a large-scale farm urinates or defecates, the waste falls through slatted floors into holding troughs below. Those troughs are periodically flushed into an earthen hole in the ground called a lagoon in a mixture of water, pig excrement and anaerobic bacteria… When storms like Florence hit, lagoons can release their waste into the environment…  If the untreated waste enters rivers, for example, algal blooms and mass fish die-offs can happen, as they did in 1999.” Additionally, the health effect on humans living nearby is also dire.

Oh, and that pound of almonds from before? It requires 526 gallons of grey water, due to pollution caused by fertilizers and pesticides. That’s 1,230 gallons of water FOR ONE POUND OF ALMONDS!

Required reading after this post:

Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming

Kiss the Ground: How the Food You Eat Can Reverse Climate Change, Heal Your Body & Ultimately Save Our World

The Soil Will Save Us: How Scientists, Farmers, and Foodies Are Healing the Soil to Save the Planet

Big farms are killing us all

Big farms being an immediate ecological disaster waiting to happen. But unreasonable demand for cheap produce and an unrelenting desire to grow produce when and where it shouldn’t be grown meansbig farms also lack the foresight to implement any meaningful regenerative practices.

And the government sure isn’t doing anything – which some farmers are slowly realizing, too late.

In an article by the Scientific American, it’s estimated that we only really have 60 years of farming left if soil degradation continues. Because when three centimeters of topsoil takes 1000 years to create (we’ve already degraded about a third of the world’s soil because of destructive farming techniques and deforestation) we don’t have many seasons left to farm the way we currently are.

When we see pomegranates growing in the middle of the desert, picture-perfect produce of all kinds available year-round, and an easy availability of very cheap meat… it’s really not all that surprising.

What foods are the biggest issue and why?

The extremely simple, short answer? Animal products.

It’s tempting to look at fruit, vegetables or especially nuts as a big culprit… I mean it takes one gallon of water for one almond to grow! (And these almonds are grown in California, in areas prone to drought.) That being said, meat and animal products in general are by far the biggest culprit.

A few scary stats on the water footprint of meat:

Producing one pound of beef takes an estimated 1,581 gallons of water, which is roughly as much as the average American uses in 100 showers. (source)

The global water footprint of animal production amounts to 2,422 billion m3 /year (87% green, 6% blue, 7% gray). (source)

Agriculture makes up “approximately 80 percent of the Nation’s consumptive water use and over 90 percent in many Western States” (source). Consumptive water is water that’s used but doesn’t directly go back into a system like a river.

The long, hard truth many people need to accept is that eating meat and other animal products is unsustainable in the system we typically operate in. I don’t explicitly advocate for veganism (here’s my take on the whole plant-based diet thing), but there’s no way around it.

The most effective way to reduce your water footprint is to stop eating meat.

What can I do to reduce my water footprint?

Because this is such a huge topic, I’d like to turn you loose with 5 practical ideas on how to reduce your personal water footprint through your diet.

stop eating meat

Duh. But here’s a little more context – and numbers, for the science nerds among you:

In industrialized countries, the average calorie consumption is about 3,400 kcal/day (FAO, 2011); roughly 30% of that comes from animal products. When we assume that the average daily portion of animal products is a reasonable mix [of meat and dairy]… we can estimate that 1 kcal of animal product requires roughly 2.5 L of water on average. Products of vegetable origin, on the other hand, require roughly 0.5 L of water/kcal, this time assuming a reasonable mix of cereals, pulses, roots, fruits, and vegetables. Under these circumstances, producing the food for 1 d costs 3,600 L of water. For the vegetarian diet… this reduces the food-related water footprint to 2,300 L/day, which means a reduction of 36%.  (source)

Essentially, reducing your meat intake drastically means a 36% reduction in your food-related water footprint. The Water Footprint Calculator suggests it may be even more dramatic than that: they state the US average diet requires 1395 gallons of water. My vegetarian diet? Only 790.

Try meatless Mondays or only serve animal products for one meal of the day to get started (or encourage recalcitrant family members).

research and cut out other water-hungry foods

Animal products aren’t the only culprit here. Produce, starches, grains, and all other foods have a variety of water footprints that vary widely. Making a few swaps of one type of fruit or vegetable over another may also have a significant impact on your water footprint. This simple visual or this PDF are great ways to take a look at the water footprint of common foods.

Example 1: 8 oz of lentils requires around 570 gallons of water, whereas a soy burger of the same size requires 174.7 gallons. (Taken from an LA Times graphic.)

Example 2: One 250 mL cup of coffee requires 37 gallons of water to produce, whereas the same amount of tea requires 8 gallons of water.

On that note…

The most effective way to reduce your water footprint - PollyBarks.com

Avoid eating processed foods

Not only do they tend to be full of artificial flavors to make them more addictive, processed foods also require a lot more water! It makes sense when you think about it.

Processed foods have a water footprint from the food itself plus the additional water needed to process, package, and mitigate pollution from the factories they come from. Sticking to unprocessed foods means a smaller water footprint and a chance to get to know real food better.

reduce food waste

As this particular particularly poignant quotes states: “Up to 40 percent of the food in the United States is never eaten. But at the same time, one in eight Americans struggles to put enough food on the table.” (source) We live in an economy that is linear and therefore accepts waste as the natural – and even necessary – way of things. Our economy even encourages waste to artificially inflate prices and continue the buying cycle.

One of the big goals of zero waste – which many people forget – is to completely re-imagine the economy. Reducing your food waste (and composting what’s left over) is a great introduction for anyone into the idea of a circular economy, ie. one in which waste is designed out. Cultivating a circular economy can help to reduce waste in production, eradicate food waste, and make sure that food is distributed fairly to meet the needs of everyone.

But while we wait for a full circular economy to emerge, we can do our own part in fighting food waste. Watch my food waste eradicating workshop for more specific tips!

Take this food quiz and make more changes

For even more ideas on how to reduce your food water footprint, I – like always – eoncourage you to audit yourself. FoodPrint offers an in-depth assessment on your personal food footprint which then shows you ways to make simple swaps.


Zero waste is so much more than the trash we see; in fact, our biggest impact on the planet is in the big systems we can’t see or directly influence. Eat smarter, think harder, and opt our of unethical, unsustainable systems!