The Water Tap: Our thirst for beef may be harming fish, new research finds

This story was originally published by St. George Spectrum & Daily News, view source here.

As part of this new water series, each Friday (Saturday in print) we will be addressing a new topic that is relevant to water security in Iron and Washington counties. Check back each week for updates on ongoing water issues, interviews with experts, and explorations of how we can ensure a better water future for the growing communities in southwestern Utah.

The Colorado River has less water than it once did. It’s a problem for the states that have divvied up its dwindling supply, for the recreation users whose boats skim its sandy bottom and for the thirsty Cottonwood trees that line its banks.

Now, new research has found that falling river levels are also a problem for hundreds of species of Western fish and that the fault may lie with the beef industry.

“We didn’t set out to investigate the water requirements of cattle feed crops specifically,” said Brian Richter, a professor at the University of Virginia and the lead author on the study just published in Nature Sustainability. “We really started with wanting to gain a better understanding of the extent to which rivers and streams across the United States are being depleted or being dried up because of human uses.”

What they found was that crop irrigation, specifically for cattle feed crops like alfalfa, grass hay and corn silage, is the single largest consumptive user of water at both national and regional scales. Growing these crops for cows accounts for 23% of all water use nationally, 32% in the western United States and 55% in the Colorado River basin.

“We were able to break down water use to a finer level of definition than we had seen in previous research by others,” said Richter. “And that included being able to see how much water was going to each individual crop, you know, to cotton, to corn, to sugar beets, to alfalfa.”

These figures align with local estimates from the Central Iron County Water Conservancy District, which show that agricultural irrigation accounts for up to 75% of water depletion in Cedar Valley, or about 22,000 acre feet annually. One acre foot of water is the amount that would be required to fill an area about the size of a football field to a depth of one foot.

A 2017 Census of Agriculture County fact sheet from the United States Department of Agriculture showed that alfalfa and other cattle feed made up a majority of Iron County crops, with forage crops listed as occupying nearly 60,000 acres of the county’s irrigated land.

Allocating 55% of water across the Colorado River basin to feeding cattle is a choice that has consequences for all manner of plants and animals. In the recent study, Richter’s group focused on the impacts to freshwater fish. The researchers estimated that 60 different fish species in the Western U.S. are at increased risk of local extinction due to declining river levels, with 53 of those species’ imperilment directly tied to the irrigation of cattle-feed crops.

Not only is this loss of fish biodiversity a concern for fishermen and the overall health of river ecosystems, but the decline of sensitive species due to over-consumption of water ends up costing big in species recovery efforts. Actions to recover habitat and restore health to fish species listed as part of the Endangered Species Act now tip the scale at more than $800 million per year.

Richter anticipates that, with reduced rainfall, lesser snowpack and increased evaporation due to rising temperatures, this situation will only worsen with time unless major changes are made to the way we irrigate crops.

“The Colorado river system is really in a pretty dangerous situation right now,” said Richter. “The level of water consumption relative to the amount of water that flows through that river system every year, it’s gotten out of balance. We’re over-consuming the water in the Colorado River system by 15 to 20%. And that situation is going to get worse in the coming decades because the climate is warming.”

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