What is virtual water? Water embedded in commodities It is an essential factor in calculating the real water use of a country, or its water footprint sources

How Important Is It? After Sowby, R (2015). America’s water footprint: 2,000 gallons per person, every day. Wasatch Water Review. http://www.wasatchwater.org/u-s-water-footprint-2000-gallons-per-person-every-day/

Virtual Water Trade Global virtual water trade 67% crops 33% livestock products 10% industrial products The regions with a significant net virtual water import are: - Central and South Asia - Western Europe, North Africa - Middle East sources

Top 5 virtual importing countries (1995-1999) COUNTRY NET IMPORT VOLUME (109 m3) Sri Lanka 428.5 Japan 297.4 Netherlands 147.7 Korea Rep. 112.6 China 101.9 Chapagain and Hoekstra, 2003. Virtual water trade: A quantification of virtual water flows between nations in relation to international trade of livestock and livestock products, in Hoekstra, AY ed., Virtual water trade: Proceedings of the International Expert Meeting on Virtual Water Trade. Water Footprint Org. http://waterfootprint.org/media/downloads/Report12.pdf What is meant by “net” volume?

Gross Virtual Water Import and Export by Region Chapagain and Hoekstra, 2003. Virtual water trade: A quantification of virtual water flows between nations in relation to international trade of livestock and livestock products, in Hoekstra, AY ed., Virtual water trade: Proceedings of the International Expert Meeting on Virtual Water Trade. Water Footprint Org. http://waterfootprint.org/media/downloads/Report12.pdf For the period of 1995-1999

Virtual Water Imports - Exports Which regions are more dependent on other regions? Chapagain and Hoekstra, 2003. Virtual water trade: A quantification of virtual water flows between nations in relation to international trade of livestock and livestock products, in Hoekstra, AY ed., Virtual water trade: Proceedings of the International Expert Meeting on Virtual Water Trade. Water Footprint Org. http://waterfootprint.org/media/downloads/Report12.pdf

Top 3 virtual exporting countries (1995-1999) COUNTRY NET EXPORT VOLUME (109 m3) USA 758.3 Canada 272.5 Thailand 233.3 Chapagain and Hoekstra, 2003. Virtual water trade: A quantification of virtual water flows between nations in relation to international trade of livestock and livestock products, in Hoekstra, AY ed., Virtual water trade: Proceedings of the International Expert Meeting on Virtual Water Trade. Water Footprint Org. http://waterfootprint.org/media/downloads/Report12.pdf What are the ramifications of being an exporter of virtual water?

From Whom to Where? Mahtani, R (2012). Assignment 2 and 3: Virtual Water Flows, in ARCH 3230: Systems, Sites and Buildings. https://arch3230roshnimahtani.wordpress.com/2012/09/18/assignment-2-virtual-water-flows/ https://arch3230roshnimahtani.wordpress.com/2012/09/

Global virtual water trade between nations: top 10 crop products (1995-1999) % OF THE VIRTUAL WATER TRADE wheat 30.20 soybean 17.07 rice 15.36 maize 8.85 raw sugar 7.20 barley 4.88 sunflower 2.71 sorghum 2.01 bananas 1.97 Source: A.Y. Hoekstra; P.Q. Hung. Virtual water trade - A quantification of virtual water flows between nations in relation to international crop trade.

Water requirement equivalent of main food products UNIT WATER (m3 per unit) cattle head 4,000 sheep and goats 500 fresh beef kg 15 fresh poultry 6 cereals 1.5 citrus fruits 1 palm oil 2 roots and rubber Source: FAO, 1997. Published in the UN World Water Development Report.

Hoekstra and Chapagain, 2007

Put these Values in Context It takes ~2,500 liters to fill an Olympic-sized swimming pool. How can it take so much water to produce these items? Where do you think it goes?

Water Use vs. Virtual Water Flow Farmer Food Processer Retailer Waste Water Consumer 15,340 liters CROP WATER Data from Hoekstra, AY (2012). The Hidden Water Resource Use Behind Meat and Dairy. Animal Frontiers, 2(2): 3-8. 1300 kg GRAIN + 7200 kg ROUGHAGES + 24,000 l DRINKING + 7,000 l SERVICING 1 COW 200 kg BEEF 2400 liters in one burger

Put these Values in Context Virtual Water Calculation Exercise Estimate the number of cotton t-shirts you own. Multiply by the virtual water content (2000 l/shirt) How many liters of virtual water? Estimate the number of leather shoes you own. Multiply by the virtual water content (8000 l/pair) How many liters water? Add the virtual H20 content from both items together. Divide by 2,500 liters/Olympic-sized swimming pool. How many Olympic-sized swimming pools does this equal?

Put these Values in Context What is the minimum quantity of water needed for a person per day? The World Health Organization says “about 20 liters per capita per day should be assured to take care of basic hygiene needs and basic food hygiene,” as well as for drinking. How many people could the virtual water of your shirts and shoes support for one day?

Amount of Virtual Water per Food per Country in m3/ton U.S. China India Russia Australia Brazil Italy World Avg Rice 1903 1972 4254 3584 1525 4600 2506 3419 Wheat 849 690 1654 2375 1588 1616 2421 1334 Corn 489 801 1937 1397 744 1180 530 909 Beef 13193 12560 16482 21028 17112 16961 21167 15497 Chicken 2389 3652 7736 5763 2914 3913 2198 3918 “The big difference between the countries is due to the climate, applied technology and the amount of production related to it.” http://www.lenntech.com/water-food-agriculture.htm#ixzz3Y9dqOXkz Why the big difference in how much water it takes to produce the same food items in different countries?

Amount of Virtual Water per Food per Country in m3/ton U.S. China India Russia Australia Brazil Italy World Avg Rice 1903 1972 4254 3584 1525 4600 2506 3419 Wheat 849 690 1654 2375 1588 1616 2421 1334 Corn 489 801 1937 1397 744 1180 530 909 Beef 13193 12560 16482 21028 17112 16961 21167 15497 Chicken 2389 3652 7736 5763 2914 3913 2198 3918 “The big difference between the countries is due to the climate, applied technology and the amount of production related to it.” http://www.lenntech.com/water-food-agriculture.htm#ixzz3Y9dqOXkz “The big difference between the countries is due to the climate, applied technology, and the amount of production related to it.”

Virtual Water Needed to Maintain a Daily Diet (L/Day) After Schrier, H (2004). Virtual Water Calculation, in Virtual Water and Global Food Security: Implications for Canada. Univ. of British Columbia. http://ubclfs-wmc.landfood.ubc.ca/webapp/VWM/course/food-export-virtual-water-3/virtual-water-calculation-9/

Water Requirements of Meat The American diet requires twice as much water as diets common in some Asian and European nations. ~40% of world’s grain production went to livestock at the turn of the century. Over the past few decades, consumption of meat in developing countries has grown at a rate of about 5 to 6% per year; consumption of milk and dairy products at 3 to 4%. What are the ramifications of these statistics? How is this a water sustainability concern? Sources!

Virtual Water Case Study Water Stress in China There is a geographical mismatch between freshwater demand and available freshwater. The North China Plain shows the greatest water scarcity, with per capita water availability < 150 m3/y China has been developing: >20 major physical water transfer projects, with a total length >7,200 km, including the world’s largest the South–North Water Transfer Project (SNWTP) Zhaoa, X, Liua,J , Liua, O, Tillotsonb, M, Guanc, D, and Hubacekd, K (2014). Physical and virtual water transfers for regional water stress alleviation in China. Proceedings of the National Academy of Sciences of the USA, V. 112(4). http://www.pnas.org/content/112/4/1031.full.pdf

Virtual Water Case Study Water Stress in China From Zhao, X, Liu, J, Liu, Q, Tilotson, M, Guan, D and Hubacek, K (2015). Physical and virtual water transfers for regional water stress alleviation in China. Proc. Natl. Acad. Sci., 112(4): 1031-1035. http://www.pnas.org/content/112/4/1031

Virtual Water Transfer Within China Much greater amounts than the physical transfers Keep these maps in mind when we look at water footprints From Zhao, X, Liu, J, Liu, Q, Tilotson, M, Guan, D and Hubacek, K (2015). Physical and virtual water transfers for regional water stress alleviation in China. Proc. Natl. Acad. Sci., 112(4): 1031-1035. http://www.pnas.org/content/112/4/1031 Gm3 = giga cubic meter = 1 billion cubic meters

Virtual Water Debate Preparation Get in groups of 4 Prepare to make a case both in support and against the following statement: More of the world should rely on virtual water trade Come up with arguments for and against (10 min) Discuss the ramifications of these positions (5 min) Find out where your group members stand on this issue (5 min)

Virtual Water Debate Preparation At the beginning of the next class, students on one side of the classroom will argue for the affirmative side of the statement students on the other side of the room will argue the negative side. Only then will you learn which side of the debate you are on.