In 2016 I received 10 letters like this:
“Dear Dr. Bergen… My name is Emma. I am in 6th grade at Rime Street Elementary. My class found out on vegsource.com that it takes 2,500 litres of water to produce one kilogram of beef. Another site said 25,000 litres… all these different answers are confusing. My social teacher also showed us a video named Cowspiracy, but it didn’t help. Do you have a dependable answer?”
Eleven-year-olds aren’t the only ones asking these questions. So are consumers, retailers, and others. When the facts aren’t available, exaggerated opinions often fill the gap. A Canadian research team is providing the facts to help us answer these questions, and to help us know how to do better.
A Beef Cluster study led by the University of Manitoba’s Getahun Legesse is measuring how the environmental footprint of Canada’s beef industry is changing. They’ve already reported that each kilogram of Canadian beef generated 15 per cent less greenhouse gas in 2011 than in 1981. A new paper from this team entitled “Water use intensity of Canadian beef production in 1981 as compared to 2011” was just published in Science of the Total Environment.
What they did: They calculated the amount of “blue” and “green” water required to maintain Canada’s beef breeding herd, grow feed, background and finish cattle (including Holstein steers), and process beef in Canada in 1981 and 2011. Blue water (surface or groundwater deliberately used for a specific purpose) mainly includes cattle drinking water, water used by processing plants, and irrigation. Drinking water was easily calculated; the amount of water cattle drink depends on their age, body weight, weather, and whether they’re lactating. Blue water used to wash carcasses, beef, equipment and laundry in packing plants came from published research, World Bank statistics, and information from packers. Blue water for irrigation came from census information, expert opinion (e.g. types of irrigation systems used for different crops in B.C., Alberta and Saskatchewan), irrigation districts, and provincial government records.
Green water (rainfall) used for dryland feed production was much more challenging to estimate. They first determined which pasture types, forages, feed grains and protein crops were most commonly used in Eastern and Western Canada in 1981 and 2011. For example, using annual crops for extended grazing was unusual in 1981 but quite common by 2011. The amount of water required by each crop at different stages of production was determined from published reports. The same crop may have different water requirements depending on when and where it’s grown. For example, barley seeded in July for swath-grazing experiences different growing conditions and has different water requirements than barley seeded earlier for silage or grain. Yield records for each crop came from 82 census agricultural regions across Canada. Rainfall (green water), temperature, and soil moisture records came from 679 weather stations located within agricultural regions of Canada. Animal and crop data were combined into 49 different feeding scenarios.
What they learned: In 2011, producing a kilogram of boneless beef in Canada required 459 litres of blue water and 15,485 litres of green water. Over three-quarters of the blue water was used to produce forage and feed crops. Less than a quarter of the blue water used was consumed by animals, and well below five per cent was used to process beef. When green water (rainfall) used by feed and forage crops was included, feed and forage production accounted for over 99 per cent of total water use; drinking water was less than one per cent, and water used for beef processing was negligible.
Overall, it took 17 per cent less water to produce a kilogram of Canadian beef in 2011 than in 1981. This was mainly due to increased reproductive performance, growth rates, slaughter weights and improved crop yields.
What it means: Because beef’s water footprint is mainly due to crop production, shrinking it further will require improved water use efficiency by feed crops and forages through breeding, management, and improved irrigation practices. These steps will reduce the water footprint of agriculture overall, not just for beef production. Further improvements in feed efficiency will also improve the water footprint as well as the greenhouse gas footprint and overall competitiveness of Canada’s beef industry.
Including blue water in the calculations makes obvious sense, because we’re choosing to use that water for a specific purpose. Including rainfall (green water) may seem strange because we can’t choose where it falls. But we are choosing what the land is being used for. Most of the land and water used for feed production is used by forage crops, which also help support ecosystem services like carbon sequestration, biodiversity and healthy watersheds. In many cases, keeping grass and cattle on the land is an environmentally responsible choice. Also remember that water cycles; it isn’t used up.
This research is helping the beef industry answer important questions from the public, and is another example of how improving our production efficiency helps shrink our environmental hoofprint.
The Beef Research Cluster is funded by the Canadian Beef Cattle Check-Off and Agriculture and Agri-Food Canada with additional contributions from provincial beef industry groups and governments to advance research and technology transfer supporting the Canadian beef industry’s vision to be recognized as a preferred supplier of healthy, high-quality beef, cattle and genetics.