Water
Dropping meat and other animal products is the biggest cut in water use a household can make
About 70% of the world’s freshwater goes to agriculture[5], and about 80% of our agriculture is used for farm animals[6]. A single dairy cow can drink over 40 gallons of water a day[7] and eat over 100 pounds of feed that all had to be grown and watered first[8]. Just one quarter-pound beef patty takes about 116 gallons of water from rivers, lakes, and wells[9], as much as nearly seven showers[10]. Counting the rain that grows its pasture and feed, it is closer to 460 gallons, or about 27 showers[1][10]. Avoiding meat and dairy is the single biggest way to cut the water footprint of what you eat[2]. If you cared about saving water, you would stop eating animals.
What the evidence says
The main points first. Every claim is tied to a source below.
Our World in Data · Environmental impacts of food production
70% of the world’s freshwater withdrawals go to agriculture
According to Our World in Data, 70% of the world’s freshwater withdrawals go to agriculture[1]. Farm animals have to eat and drink too, and about 80% of our agriculture goes to animal feed[4], so most of that water grows corn, soy, and grass for farm animals instead of food for people. A cow can drink over 40 gallons of water a day[5], on top of the water it takes to grow the 100+ pounds of plant food she can eat in a day[6]. Most of the water behind cow flesh goes into growing the feed, not into the trough[3]. Eating the plants ourselves skips that extra step[3], and we would use magnitudes less water if we didn’t harm or kill animals.
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Our World in Data · Poore & Nemecek (2018)
Farm animals drink a lot of water, and growing their feed takes even more
Mekonnen and Hoekstra worked out the full water cost of animal products[1]. Per calorie or per gram of protein, meat and dairy take far more water than beans, grains, and most vegetables[1][2], and most of that water goes into growing the feed, not filling the animals’ troughs[1]. On top of that, a cow can drink over 40 gallons a day[3][4]. Eating plants directly is infinitely more efficient.
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Our World in Data · water pollution · Poore & Nemecek (2018)
Cutting animal products saves more water than any other change to a diet
Poore and Nemecek found that meat and dairy cause most of agriculture’s water pollution and a large share of the water it withdraws[1]. When researchers modeled diets across the EU, a vegetarian diet had the lowest water footprint[2]. Eating more plants and fewer animal products is the biggest single way a household can save water.
Read full article →Articles
Eating plants is the biggest water saving a household can make
Most of the water farms use goes to growing feed for farm animals, and meat and dairy take far more water per calorie and per gram of protein than beans, grains and most vegetables. Cutting them out saves more water than any other change you can make to what you eat.
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Sources
Papers and datasets. Each card keeps its caveats, including small samples and single-animal cases.
[1]Ecosystems, 2012 · Meta-analysis
Animal products have far bigger water footprints than crops, mostly because of feed
Mekonnen and Hoekstra found that animal products have far larger water footprints per calorie or per gram of protein than starchy crops, pulses, and most vegetables, mainly because of the water used to grow the animals’ feed.
[2]Science · Meta-analysis
Meat and dairy cause most of farming’s water pollution and much of its water use
Poore and Nemecek found that meat and dairy cause most of farming’s water pollution and a large share of its freshwater withdrawals. Cutting them out is one of the biggest ways to save water through what you eat.
[3]Clean Water Action · Review
Plant-based diets shrink household water footprints
Clean Water Action says eating plant-based cuts a household’s water footprint and improves health markers at the same time.
[4]Ecological Indicators, 2013 · Observational
A vegetarian diet had the smallest water footprint of the EU diets modeled
Vanham, Mekonnen, and Hoekstra modeled several diets for the EU, and the vegetarian diet had the lowest water footprint. The gap came from animal products.
[5]Our World in Data · Review
Most animal products use far more freshwater than starchy crops and pulses
Using Poore’s data, Our World in Data shows that most animal products take far more freshwater per kilogram, per 1,000 kcal, and per 100 g of protein than starchy crops and pulses. Farming accounts for about 70% of the world’s freshwater withdrawals.
[6]Our World in Data
About 80% of the world’s farmland is used for meat and dairy
About 80% of the world’s agricultural land is used for meat and dairy, counting both pasture and the land that grows feed crops.
[7]University of Nebraska-Lincoln Extension
A dairy cow can drink more than 40 gallons of water a day
According to the University of Nebraska-Lincoln Extension, a dairy cow producing milk can drink more than 40 gallons of water a day, and more in hot weather.
[8]Dairy Cattle Extension
A high-producing dairy cow eats about 110 to 120 pounds of wet feed a day
Dairy extension figures show that high-producing dairy cows eat about 110 to 120 pounds of wet feed a day, or 50 to 55 pounds of dry matter.
[9]University of Michigan CSS, 2018
A Beyond Burger uses 99% less water and 93% less land than a cow-flesh burger
Heller and Keoleian at the University of Michigan found that a 1/4 lb Beyond Burger uses 99% less water, 93% less land, and 46% less energy than a 1/4 lb U.S. cow-flesh burger, and produces 90% fewer greenhouse gases. The cow-flesh burger consumes 437.7 liters of water and the Beyond Burger 3.27 liters, or 218.4 versus 1.1 liter-equivalents once weighted for water scarcity.
[10]U.S. EPA WaterSense
The average shower uses about 17 gallons
The EPA’s WaterSense program says the average shower lasts about 8.2 minutes and uses about 17.2 gallons of water.