Water usage has declined according to a new study
The agriculture industry is the largest user of ground and surface water in the United States. Along with the food manufacturing industry, it accounts for approximately a third of the nation’s consumptive water use. Talk about the world, and you’re looking at around 70%. Irrigated operations also account for roughly half of the total value of crop sales in the United States.
Given that some scientists believe that within the next 50 years, the nation could decrease its freshwater supply by as much as a third, that makes a new study by the University of Illinois look a little rosy. According to the researchers, water use by the agriculture industry has actually decreased over a 15-year period, from 1995 – 2010. The comprehensive study looked at water withdrawals in U.S. agriculture and food production over that time period and found an 8.3% drop for crops and a 14% decline for livestock use.
The main trend was due to a combination of factors, such as increasing efficiency of the irrigation system, the growth of genetically modified crops, a change in domestic per-capita income and a changing of grown crops.
While the overall results showed a decline, Sandy Dall’erba, regional economist at U of I and co-author on the study, says that the water use between industry are vastly different from one another.
“One needs to identify the drivers of water use by crop as they differ from one commodity to the next, so water-saving strategies for one crop may not be relevant for another one,” Dall’erba explains. “For instance, water use in cereal grains, fruits and vegetables is mostly driven by the efficiency of the irrigation system, domestic per-capita income and sales to the food processing industry. If irrigation is more efficient, water demand decreases. When demand for fruits and vegetables decreased in 2005-2010 during the financial crisis, so did demand for water.””
Oilseed crops, on the other hand, have experienced a 98% increase in water demand. The change is primarily driven by international supply-chain linkages. It means foreign companies, mostly in China, have purchased large amount of U.S. oilseed crops for further processing.
In their study, the team looked at 18 primary factors which drive U.S. water withdrawals across eight crops, six livestock categories and 11 food manufacturing industries. Based on data from Exiobase, a global supply-chain database, they included water that’s embedded into the production at all stages of the domestic and international supply chain, from crops and livestock to processed food production – highlighting the interconnectedness of global agribusiness.
As an example, crops produced in the U.S. may rely on fertilizers produced in a different country. Likewise, soybeans produced in the U.S. could be used for food processing in China or to feed European livestock.
Trade wars have also played a factor due to changing supply-chain linkages. As an example with the China trade war, imports of oilseeds from that country is shifting to South America and Europe. The U.S. exported fewer soybeans and pork to China over the last two years; therefore, less water was embedded into those exports. However, the next few years under a new U.S. administration may see an improvement in these relationships.
Changing eating habits were also found to play a part.
“There has also been a shift in consumer demand from red meat to white meat in the U.S. People consume less beef and more chicken, which require 3.5 times less water per pound of production,” Dall’erba says. “Those trends in consumption and taste have helped the U.S. reduce water use for livestock by 14%.”
Dall’erba states that the questions addressed in this research are extremely relevant for any country that is heavy on agricultural production.
“Namely, how can we feed the 10 billion people we expect to be at the global level by 2080, considering that we cannot necessarily expand the amount of land that’s going to be used? And, given climate change, there is quite a lot of uncertainty with respect to the availability of water needed to grow crops and feed livestock in the years to come.”