Beef Issues Quarterly Archive

Is the water research well running dry? Scientific data on beef’s water consumption urgently needed to counter activist claims

Is the water research well running dry? Scientific data on beef’s water consumption urgently needed to counter activist claims

by Jude L. Capper, Ph.D., Livestock Sustainability Consultant – Bozeman, MT

Summary

Writing an article on water use in beef production seems somewhat ironic in a month when the U.S. Drought Monitor map (http://droughtmonitor.unl.edu/) shows a sea of yellow, orange and red drought-stricken states. Nonetheless, it’s when water supplies are restricted that our industry is most likely to come under fire (pun intended) from those opposed to animal agriculture.

Greenhouse gases remain the major sustainability focus for campaigns aimed at reducing or eliminating meat consumption – the recent release (and subsequent retraction) of a statement from USDA supporting Meatless Mondays included the oft-heard claim from the FAO that livestock are responsible for 18 percent of global carbon emissions. However, the release also claimed “beef production requires a lot of water, fertilizer, fossil fuels, and pesticides”. Of these four resources, water is the one that consumers are most able to relate to. We cannot see, feel or touch carbon emissions, whereas water remains the single resource that we cannot function without from a biological standpoint, and the one that causes the most inconvenience when it is restricted. Lawn watering restrictions have certainly put the drought issue into context for many urban dwellers this summer and this is likely to continue as the drought causes food prices to rise.

Obviously the USDA’s "a lot of water" claim is somewhat nebulous, but without comparative data for different food sources it’s difficult to understand the magnitude of beef’s water use. Unfortunately, this is one area where the science is somewhat lacking, and the activist groups are willing to fill in the knowledge gaps for us. People for the Ethical Treatment of Animals (PETA) is currently touring the country with a demonstration in which two scantily-clad ladies pose behind a make-shift shower curtain emblazoned with the language “One lb. of meat equals 2,463 gallons of water”. Not only does the sight of half-naked ladies on city streets garner considerable attention from passers-by, but the precision of the water use figure implies that it must have been calculated on a scientific basis, regardless of whether or not it is a realistic number.

Pseudo-science
Pseudo-science tactics are not confined to well-known activist groups - a representative from a water policy project was quoted in a recent press-release from ScienceNow as saying “…people can opt to eat less meat or to switch from grain-fed beef—which, again, requires about 5,300 liters (1,400 gallons) of water for each dollar’s worth of grain fed to a cow—to grass-fed beef, which typically requires only the rainwater falling on a pasture”. Putting aside the fact that grass-fed beef does not appear to require any drinking or irrigation water in this example, a metric based on water use per dollar of grain fed is almost impossible to understand in isolation or to compare to other water use. Indeed, it is tempting to suggest that the figures quoted by groups with an anti-animal agriculture agenda may have been intentionally inflated in order to dissuade consumers from eating meat. However, some methodologies will invariably produce water use figures far higher than would have been predicted from animal performance, crop/pasture production and processing.

Defining water use
The problem lies in how we define water use or consumption. Both words imply that a resource is depleted, exploited or no longer available. Within the water cycle during which water is taken from the ground, used by plants or animals, evaporated to the atmosphere and returned to the ground in a continuous process, it’s difficult to consider water as a finite or limited resource that is “consumed”. You may notice that within this article I often use the word “employ” when discussing the relationship between cattle and water. This may be a better descriptor than “consume” as beef production often simply occupies water for a time, before that water is employed again for another purpose rather than suggesting that it is destroyed or irrefutably changed by utilization. However, when water is being drawn from aquifers faster than it can be replenished, the cycle is out of balance, leading to depletion of groundwater resources that can be considered "consumed".

Water consumption could therefore be defined simply as the total quantity of water extracted from underground or above-ground sources (and not returned to that source) per unit of beef produced. This definition works relatively well when water is used in a particular process and then evaporates to the atmosphere (“blue water”) or is contaminated to the extent that it is no longer usable in the future and needs to be diluted to reach acceptable levels of contamination (“grey water”). Yet how do we classify water employment by a processing plant that extracts water from the nearby river, cleans it for use in the plant and returns it to the river in a more sanitary condition than the original extract? In this case, employment is complicated not only by the water’s return to the source but the improved quality of the returned water.

Should this count as a water credit for the processing plant in the same way that companies may be able to claim carbon credits in future?

The most debated classification of water consumption is "green water" which is essentially a measure of rainfall. The premise behind inclusion of green water in consumption calculations is that growing crops or pasture employs rainfall that could otherwise be used for natural vegetation, and therefore should be allocated to those specific crops. Yet by including green water in total water consumption, beef production in Mississippi (average rainfall of 59 inches/year) could be considered to consume almost four times more water per unit of beef than beef production in Montana (average rainfall of 15 inches/year). The potential policy implications of this difference are considerable. Most scientific researchers currently involved with water consumption analysis do not include green water, however, it is included in figures propounded by groups such as the Water Footprint Network (http://waterfootprint.org).

Usage analyses
The most comprehensive analysis of water use within U.S. beef production was published in a 1993 by researchers at UC Davis. This paper analyzed water consumption on a regional and national basis, included animal performance, crop production, irrigation and processing within the model, and concluded that 441 gallons of water were employed per pound of boneless beef produced. A later paper examining resource use in beef production reported a 12 percent decrease in water consumption per pound of beef between 1977 and 20077. Both papers are peer-reviewed and published in the Journal of Animal Science, but neither provides us with an inarguable figure for beef’s water consumption. The 1993 paper is almost 20 years old - significant changes have occurred in animal performance, crop yields and irrigation patterns over that time which will impact the quantity of water employed per unit of beef. The 1977 vs. 2007 analysis uses modern-day production data, but ends at the point of harvest and therefore does not include water employed during processing.

The aforementioned Water Footprint Network’s analysis of water consumption for beef production includes the assumption that in an “industrial beef system” (i.e. those characteristic of the USA and Canada), it takes an average of three years before the animal is slaughtered to produce 441 pounds of boneless beef. These figures differ considerably from the U.S. average age at slaughter of approximately 15 months and boneless beef yield of ~605 lb. Results of water consumption analyses are directly related to the underlying assumptions within the model – if the assumptions are incorrect, the resulting water use will similarly be incorrect. It is therefore not surprising that the Water Footprint Network’s figure of 1,857 gallons per pound of boneless beef is over four times higher than the 441 gallon UC Davis estimate. However, the Water Footprint Network has gained considerable credibility for its water analyses simply on the basis of being a third-party agency that is not affiliated with the beef industry and that is therefore considered to produce unbiased results.

The current drought has highlighted the critical importance of water for food production and it seems inevitable that this will be a more immediate sustainability issue than carbon emissions. There is a critical need for scientific, comprehensive, up-to-date data with which to counter the extensive misinformation relating to water employment by beef production so that we are not wrong-footed when the issue rises to the top of consumer, retailer and policy-maker agendas. While we may not welcome figures that will almost certainly demonstrate that beef employs more water per pound than apples, wheat or poultry, without this data we are left defenseless against inflated claims from the activist groups. If we continue to focus on greenhouse gases as the sole arbiter of environmental sustainability, and do not concentrate efforts on water resources, we may feel the long-term effects of the current drought in more ways than one.

Resources


The FAO claim that livestock are responsible for 18 percent of global carbon emissions has been discussed in previous issues of BIQ and has been disproved by researchers at the University of California, Davis. Nonetheless, it continues to be used to further anti-animal agriculture agendas.

ScienceNOW (2012). Is Agriculture Sucking Fresh Water Dry? 2/13/2012. Available at: http://news.sciencemag.org/sciencenow/2012/02/is-agriculture-sucking-fresh-wat.html?ref=hp

For more discussion of this metric and a comparison to national water use figures see: Capper, J. L. (2012). Flawed Water Use Claims are Huge Threat to Sustainability. 2/23/2012. Available at: http://bovidiva.com/2012/02/23/flawed-water-use-claims-are-huge-threat-to-beef-sustainability/

Water Footprint Network (2012). Water Footprint FAQ – Technical Questions. Available at: http://www.waterfootprint.org/?page=files/FAQ_Technical_questions

Current Results (2012).Average Annual Precipitation by State. Available at: http://www.currentresults.com/Weather/US/average-annual-state-precipitation.php
Beckett, J.L., and Oltjen, J.W. (1993) Estimation of the water requirement for beef production in the United States. Journal of Animal Science 71, 818-826. Available at: http://jas.fass.org/content/71/4/818.full.pdf

Capper, J.L. (2011) Replacing rose-tinted spectacles with a high-powered microscope: The historical vs. modern carbon footprint of animal agriculture. Animal Frontiers 1, 26-32. Available at: http://animalfrontiers.fass.org/content/1/1/26.full.pdf

Tags: Beef Issues Quarterly, Expert Commentary, Summer 2012

September 22, 2012