Chapter 4: Emerging Water Shortages

1. Chapter 4: Emerging Water Shortages By Cody McNutt and Jennifer Ng

2. Lake Chad • Surrounded by Cameroon, Chad, Niger, and Nigeria-all countries with fast growing populations • Shrunk 96% within 40 years • High demand for irrigation water and declining rainfall draining dry the rivers and streams that feed Lake Chad

3. Africa’s Lake Chad

4. Overview • Water demand has tripled over the last 50 years • Drilling of millions of irrigation wells has pushed water withdrawals beyond recharge rates • Climate change affects water supplies • Rising temperatures = higher evaporation rates, altering rainfall patterns, and melting glaciers • Countries pressing against the limits of water supply satisfy the growing need of cities and industry by diverting irrigation water from agriculture and importing grain to offset the loss of productive capacity • Water = Food • One Person = 4 liters of water/day • Production of food = 2,000 liters • 70% water = irrigation • 20% water = industry • 10% water = residential purposes

5. Risk of Water Shortages

6. Water Tables Falling • Fossil aquifers are not replenishable • Depletion brings pumping to an end • For more arid regions, loss of irrigation water means end of agriculture • North China’s Plain’s water table, producing over ½ of the country’s wheat and a 33% of corn, is dropping 3 meters/yr • Wheat farmers pump from a depth of 300 meters, raising pumping costs so high that farmers are forced to abandon irrigation

7. Water Tables Falling • China • Mining underground water near the Hai, Yellow, and Huai Rivers • Takes 1000 tons of water = 1 ton of wheat • 40 million tons of wheat feeds 120 million Chinese compared to 2 billion • India • 100 million farmers drilled 21 million wells, investing $12 billion in wells and pumps • Electricity blackouts occur where ½ is used to pump water from depths up to a km

8. Water Tables Falling • In southern India, falling water tables dried up 95% of wells owned by small farmers • Irrigated land is reduced by half over a decade • Farmers are forced to return to dryland farming

9. Water Tables Falling • Some use modified oil-drilling technology to reach water, going as deep as 1,000 meters • 15% of India’s food supply produced by mining groundwater • Texas, Oklahoma, and Kansas – 3 leading grain-producing states – the underground water table dropped by more than 30 meters

10. Water Tables Falling • Colorado River • Drawn by AZ, CA, CO, NV, NM, UT, WY • Irrigated area decline from 1997-2002 • CA and CO dropped 2% and 24% respectively

11. Water Tables Falling • Iran • 71 million people • Overpumping aquifers by an average of 5 billion tons of water/yr – 33% of its annual grain harvest • Water table is falling 2.8 meters/yr • Saudi Arabia • 25 million people • Water-poor as it is oil-rich • Wheat harvest dropped from 4.1 million tons in 1992 to 2.7 million tons in 2007, 34%

12. Water Tables Falling • Yemen • 22 million people • Annual water extraction of 223 million tons exceeds annual recharge of 42 million tons, water table dropping 6 meters/yr • Grain production falling by 2/3 over the last two decades • Now imports 4/5 of its grain supply • Ranks 24th of failing states

13. Water Tables Falling • Mexico • 107 million people • Demand of water is outstripping supply • Guanajuato – water table is falling 2 meters or more a year • Sonora farmers used to pump water from the Hermosillo aquifer at a depth of 35 ft. Now more than 400 ft. • 51% of the water extracted from underground is from aquifers being overpumped

14. Water Tables Falling • Overpumping of aquifers is happening in many countries • Depletion of aquifers and the harvest cutbacks could be simultaneous • Depletion of aquifers = unmanageable food scarcity

15. Rivers Running Dry • Colorado River • Major River in the southwestern US • Yellow River • Largest river in northern China • Nile River • Lifeline of Egypt • Indus River • Supplies most of Pakistan’s irrigation water

16. Rivers Running Dry • Colorado River • Rarely makes it to the sea • Goes through CO, UT, AZ, NV, and CA • Demand is destroying the river’s ecosystem, including fisheries

17. Rivers Running Dry • Yellow River • Flows 4,000 km through 5 provinces before it reaches the Yellow Sea • First ran dry in 1972 and since 1985 it has often failed to reach the sea

18. Rivers Running Dry • Nile River • Before the Aswan Dam was built, 32 billion cubic meters of water reached the Mediterranean each year • After the dam, increasing irrigation, evaporation, and demands reduced its discharge to less than 2 billion cubic meters

19. Rivers Running Dry • Indus River • Originating in the Himalayas and goes into Indian Ocean • Demand has made the river run dry in its lower reaches • Population of 164 million, Pakistan ranks 12th on the 2007 list of failing states • Allocating water among competing interests is part of an emerging politics of resource scarcity

20. Lakes Disappearing • As river flows are reduced lakes have been shrinking; Lake Chad Central Africa, the Aral Sea Central Asia, and the Sea of Galilee • Most notable losses the Aral Sea cotton farming used up all the water which raised salt content and killed fish

21. Aral Sea Today

22. China, Got Water? • 1,000 lakes have disappeared over the past 50 years • Average rate of 20 lakes lost each year • The government had set up 160 wetland protection zones and invested heavily in measure to prevent pollution

23. How much is water in the Desert, an Economy lesson • It takes 14 tons of water to make a ton of steal which sells for $560 • It takes 1,000 tons of water to grow a ton of wheat which sells for $200 560/14 = $40 per ton of water 200/1000 = $0.20 per ton of water • Cities use more water than farming and have a higher need for water

24. Water Law • Riparian vs. Appropriation “First in time, first in right” • Colorado water law • Right to use, who has more right? • Do cities have greater need than farmers • Will water become the new oil when countries don’t produce their own, or have a food supply • International water wars?

25. Solutions or “The End” • How much water is there, how much water was there? • Can we get more water? • Most water distputes are local and in high population areas, not worldwide • Over population and standards of living, living on less

26. THE END