While livestock and poultry production in the United States has risen substantially since 1960, the amount of water used has dropped, according to research from University of Nebraska’s Water for Food Global Institute. A few factors have contributed to this drop in water use, such as selective breeding, genetic engineering and the larger sizes of animals enhanced by supplements, which has led to generally more food gained from each animal.
Water productivity for six animal products including beef, pork, chicken, turkey, milk and eggs, improved between the years 1960 to 2016. Milk was produced about five times more water-efficiently in 2016 than in 1960; pork almost four times more efficiently; chicken, turkey and eggs, collectively, around three times more efficiently; and beef almost two times as efficiently. Beef is a particularly large water user.
But there is more to consider over time, said lead author, Dr. Mesfin Mekonnen:
Globally, we see that the population is growing, income is improving, and with that, the demand for livestock products is increasing. When comparing a livestock product to a nutrient-equivalent crop product, livestock demands more water. So with the increase in demand for animal products, there will be more water demand, creating more pressure on the limited available water.
As the demand for meat, dairy and other animal products growing around the world, the demand on water, land and other resources are growing, too. This can contribute to conflict over limited resources. Moreover, the US factory farm model (i.e., CAFOs), on which these size and efficiency gains depend, cause their own problems like water, air and land pollution, public health impacts, harm to farm workers, and market consolidation that put smaller farms out of business, among other problems.