Water Usage & Scarcity Takeaways
Takeaways are key points detailed and referenced in the Water Usage & Scarcity section
Agricultural Water Consumption
Water consumption has more impact than water withdrawals; consumed water is not returned to its original source and is not available for reuse.
Agriculture accounts for ~80% of total U.S. water consumption, mostly for irrigation.
Agricultural irrigation accounts for more than two-thirds of total groundwater withdrawals.
Irrigation, accounting for almost 80% of the nation’s water consumption, produces crops worth less than one-half of one percent of GDP (the total value of the nation’s goods and services).
Animal Ag Water Consumption
Broadly estimated, animal agriculture accounts for ~40% of all U.S. water consumption: ~38% for the share of crops specifically used for animal feed, and ~2% for direct usage on factory farms.
The factory farming system relies on millions of acres of irrigated feed crops that consume immense amounts of water; this is the central water issue for the nation.
The nation’s 3 largest crops, each primarily used for feed – corn, soybeans, and alfalfa/hay – account for ~45% of total national water consumption.
Alfalfa/hay (almost all used for farmed animal feed) accounts for almost a quarter (~23%) of total national water consumption. Corn accounts for ~15% and soybeans ~7%.
About 70% of water withdrawals for corn, soybeans, and alfalfa/hay comes from groundwater.
Meat slaughter and processing industries use large amounts of water relative to the communities in which they operate; the industry’s water pollution issues are generally a more pressing concern than usage.
Water Scarcity
Depletion of groundwater is unsustainable – a threat to public and private water supplies.
About two-thirds of groundwater usage is due to agriculture; one-third or more is due to animal ag.
The loss of groundwater and surface waters – lakes, rivers, and streams – poses an enormous threat to freshwater ecosystems and biodiversity; feed crop irrigation plays a central role in both.
U.S. aquifers are losing approximately 25 km3 (cubic kilometers) yearly; that’s about two-thirds the volume of total annual domestic water use.
The High Plains aquifer (including the Ogallala) has the largest cumulative depletion and the largest withdrawal, ~95% of which is used for irrigation.
In the 8 states overlying the High Plains aquifer, it’s likely that well over 50% of aquifer water is used for feed crop production.