Barbara Wimmel of Freiburg, Germany writes: As I have been a vegetarian for many years, one question has been on my mind for a long time. We are told incessantly to eat lots of fruit and vegetables: But isn't it true that (most? all? which?) vegetables can be grown only while needing a lot of water (and this often seems to mean irrigation)? If so what possible solution(s) exist for this problem?
Jon Fisher, spatial scientist with The Nature Conservancy and vegetarian for 21 years, answers:
I have lots of good news for you. In brief:
- As a vegetarian your water footprint is almost certainly much lower than that of most meat eaters.
- There is great data on the water footprint of various vegetable foods, so you can choose options that require less water.
- There is even good data on how water scarcity varies across the globe, so you know where your produce is from (most health food stores prominently disclose that) you can further choose food from regions where water is currently not scarce.
Fruits and vegetables are indeed more water intensive than cereals and legumes, but generally significantly less water intensive than meat. You also probably eat more grains and beans than meat eaters, and those use a lot less water to produce than meat. How much less? Well, eating a 1/3# soybean burger instead of a 1/3# beef burger saves 579 gallons, which is more water than the average American uses indoors in a week (read my analysis and references here, and get more detail here). So you could eat nothing but vegetables and fruits, and still be saving water over an omnivore. Since you’re in Germany, you may want to read a recent paper on water footprint of different diets in the European Union, which found that a vegetarian diet uses 38% less water than the “typical diet” in the EU.
The one vegetarian food that requires a similar amount of water to produce as meat is nuts (which are often grown on irrigated fields in the desert). A good place to start if you want to pick foods that don’t need as much water is this table that compares the water footprint of animal products to various plant foods. Be sure to look at the “litre/kcal” column (kcal means food Calories) since the water needed to fill you up is more important than the water footprint per product weight. You can find out about more specific foods in this water footprint product gallery, and if you really want to get into it you can read the report with water footprint data for 126 crops and food products.
Finally, there are huge differences in how much water it takes to grow crops in different places around the world, and how scarce water is there (due to competing demands). The report on the water footprint of crops has some good tables on how the water footprint of crops varies by country and region. You can use an interactive map of water risk (basically areas where there is a water shortage or a risk of water shortages) to identify some areas to avoid sourcing your food from if you have the choice.