As food systems in the United States become more complex and interconnected, products such as beef often impact the environment in unpredictable ways. Now, a team of scientists from the University of Pittsburgh has found that, although water is needed throughout the entire food supply, the beef industry is the least efficient in using it.

The experts designed a model to investigate the beef industry’s impact on virtual water flows – the hidden movement of water in food production – by tracing supply chains from calf production to beef consumption across the entire U.S.

“Understanding beef demands and the spatial distribution of both feed and cattle production are key for evaluating the environmental sustainability of food systems and developing improvement strategies,” said Vikas Khanna, a civil and environmental engineer at Pittsburgh.

Scientists have long known that all food production requires vast amounts of water, most of it used to produce feed. The irrigation process for feed requires water found in surface and ground reservoirs (so-called “blue water”). However, using this type of water exclusively can lead to environmental problems such as water depletion, soil degradation, or salinization.

By using an optimization-based framework and datasets on supply and demand, the researchers discovered a marked disconnect between consumption and production counties, with over 22 billion cubic meters of blue water transferred in 2017 alone (thus, a higher quantity than the Great Salt Lake, which has about 19 billion cubic meters of water).