How Much Water Does it Take?
The Food Journal
July 8, 2013
Different ways to classify our water:
According to a water study in collaboration with the University of Sweden and the FAO, “To produce the amount of food that is required to live ‘an active and healthy life’ for example, requires between two and six cubic meters of water per person per day (528-1585 gallons). Variations stem from differences in the composition of diets (more meat in the diet means that comparatively more water is required) and the climate where the food is produced (hot climates mean that more water is required to produce a given amount of food items). The annual water requirement for food security is estimated at between 1,000 to 2,000 m3/person (264-528,000 gallons).” People need a half gallon of water to drink every day. To understand the impact of this statement, it is important to know the types of water available to us.
What types of water make up the one percent we have to use?
Blue water is available in streams, lakes and underground aquifers. It is used for washing, processing and cooling machinery. Not all blue water is easily accessible, especially where it is needed. Twenty percent of the world’s blue water is found in the Amazon region. Fifty percent of accessible blue water is already committed for uses like drinking water, hygiene, industrial uses, and must also be used when the green water is not enough to keep our agriculture alive. Blue water is considered more scarce than green water.
Green water is evaporated water, water in the soil or rain water. It is used mainly for agriculture by humans. Humans are using around 26% of the total green water available.
Grey water is water polluted/used by people. It can sometimes be reused for a second purpose, depending on what the first use of the water was, like bath water being then used as gardening water.
What the water problems are:
Aquifer Depletion & Groundwater Depletion
While water is a renewable resource, our sources are changing. Since we tend to use the water from underground aquifers faster than they are being refilled, once the water is all used up, challenges will begin for people who are used to having their water come from the ground semi-conveniently. They will have to look elsewhere for their water. In China, according to the Encyclopedia of the Earth, some aquifers have been measured to be dropping twenty feet a year. Out of 3,000 feet of depth, that might not seem like that much, but unless they change their techniques of using the water, it doesn’t look like they will be slowing that rate down much. The higher the drawdown the more expensive it is to obtain the water, because the wells are deeper and need more power to move the water to the surface.
When the water is taken out of the aquifers and used, it becomes a part of the ocean water system, and researchers, as reported by the American Geophysical Union, believe that this water displacement could be causing up to 25% of the annual sea level rise. Americans alone are believed to contribute up to two percent of the rising ocean levels, and since 1900, they have lost around two Lake Eries of water.
2012 was the hottest year in the US on record, with data going back to 1895. In a slide show presented by the Global Harvest Initiative, with statistics from the National Climatic Data Center, it was also the second most extreme year with eleven disasters costing over $1 billion. One reason the drought is so concerning is because drought is the number one cause of economic loss in the US, with loss estimates up to $77 billion, depending on whether you consider livestock as a part of agriculture. The greatest loss has been from corn and soybeans. While agriculture is generally one of the larger categories affected by drought, there are other things affected too, like water supply and quality and fires. Without a very rainy spring, the soil won’t be recharged and ready for new crops.
In 2050, we are expected to have an additional two billion people, with a world population of over nine billion. In order to meet the needs of these new people as well as the rest of the world’s changing diets, we will have to nearly double our current food production. With irrigated agriculture (versus rain fed) on the rise having doubled in the past 50 years, and having much higher yields than rain fed agriculture, it seems like it will continue to rise in order to provide more food. According to the Global Harvest Initiative’s Providing Solutions to Water for Food Challenges, investing more money in things like better irrigation and drought resistant crops is key. Drought gives us an average annual global yield loss of 15%, roughly $13 billion. Seventy-five percent of severe droughts in the past 10 years have occurred in Africa, with that area being on the top of the list to have investment in new technology and practices to minimize the loss. The diet change cannot be ignored in these predictions either, with the protein consumption doubling per person by 2050. We have been able to lower our water usage in the past, lowering it by 14% for a pound of beef from 1977-2007, and lowering it by 65% for a gallon of milk.
Many feel water is not priced near its intrinsic value. We have to start thinking about the value of water versus what we are paying for it. A cotton t-shirt has up to 2,000 liters of water behind it, but we don’t give t-shirts a very high value at all when buying them, especially after thinking about how much we pay for a bottle of water. Commentary by Marty Strauss, Environmental Engineer and Molecular Biologist
Industry players in water conservation:
Technology unlocking sea water is not doing enough to meet the needs as desalination from a technical perspective is very expensive. Therefore, CPG companies are striving to understand water scarcity and solutions when evaluating crop growth and production. Kellogg, for example, is determined to do their part to reduce water use and use water more efficiently, and encouraging their suppliers to do the same.
The Journal spoke with Diane Holdorf, Chief Sustainability Officer, VP EHS, Kellogg Company. “All Kellogg manufacturing facilities have established water efficiency goals, and globally, our facilities have implemented a range of water-saving initiatives. We are engaged in efforts to understand current growing practices and providing support for more sustainable long-term solutions,” says Diane. She gives examples such as Kellogg’s work with rice farmers, the Louisiana Rice Mill and the Louisiana State University (LSU) Ag Center to create a Rice Master Grower program, which seeks to promote the management and mitigation of environmental issues in rice production, which can include water use (due to the intentional flooding of rice fields) and sometimes water quality (from runoff when fields are drained).
When asked what is one of the most promising ways for changing the way growers look at water as a potentially scare resource, Diane replied, “One of the promising ways we have worked to address water and sustainability has been as a member and funder of Field to Market: The Keystone Alliance for Sustainable Agriculture. Field to Market is a multi-stakeholder dialogue group that has brought together growers, agribusinesses, food companies and conservation groups to find ways to drive continuous improvement in agricultural practices. One of the most valuable tools developed by Field to Market has been the Fieldprint Calculator, an online program that helps farmers compute the environmental impacts, including irrigation water use, of their operations and compare them to industry averages. Growers have found the Fieldprint Calculator helpful in assessing their own performance and identifying opportunities for improvement.” Read full interview with Diane Holdorf, Chief Sustainability Officer, VP EHS, Kellogg Company
As reported by Greenbiz.com, the Ford motor company, while having an impressive track record when it comes to water use reduction, hopes to reduce water by 30% per vehicle by 2015. Water is critical to a number of manufacturing steps, including vehicle painting. Overall, large volumes of water are used in the automotive supply chain, particularly in making raw materials such as steel and aluminum.
Investors in companies can get more savvy about the water use of the companies in the food industry that they are stakeholders in. Ceres, an advocate for sustainability leadership out of Boston, developed a Consideration for Assessing Companies’ Exposure to Water Risk, asking key questions such as, “Does the company measure the quantity and quality of its wastewater discharges and does the company know which parts of its supply chain are most water-intensive?” The water issue affects all aspects of our economy and must be examined from the pocketbook to the soil to the shelf.
The Food Journal would like to thank Jane Roberts for her research, analysis and contribution to this edition.