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Chapter 4: Emerging Water Chapter 4: Emerging Water ShortagesShortages
By Cody McNutt and Jennifer NgBy Cody McNutt and Jennifer Ng
Lake ChadLake Chad
Surrounded by Cameroon, Chad, Niger, Surrounded by Cameroon, Chad, Niger, and Nigeria-all countries with fast growing and Nigeria-all countries with fast growing populationspopulations
Shrunk 96% within 40 yearsShrunk 96% within 40 yearsHigh demand for irrigation water and declining High demand for irrigation water and declining
rainfall draining dry the rivers and streams rainfall draining dry the rivers and streams that feed Lake Chadthat feed Lake Chad
OverviewOverview Water demand has tripled over the last 50 yearsWater demand has tripled over the last 50 years
Drilling of millions of irrigation wells has pushed water Drilling of millions of irrigation wells has pushed water withdrawals beyond recharge rateswithdrawals beyond recharge rates
Climate change affects water suppliesClimate change affects water supplies Rising temperatures = higher evaporation rates, altering Rising temperatures = higher evaporation rates, altering
rainfall patterns, and melting glaciersrainfall patterns, and melting glaciers Countries pressing against the limits of water supply Countries pressing against the limits of water supply
satisfy the growing need of cities and industry by satisfy the growing need of cities and industry by diverting irrigation water from agriculture and importing diverting irrigation water from agriculture and importing grain to offset the loss of productive capacitygrain to offset the loss of productive capacity
Water = FoodWater = Food One Person = 4 liters of water/dayOne Person = 4 liters of water/day Production of food = 2,000 litersProduction of food = 2,000 liters 70% water = irrigation70% water = irrigation 20% water = industry20% water = industry 10% water = residential purposes10% water = residential purposes
Water Tables FallingWater Tables Falling
Fossil aquifers are not replenishableFossil aquifers are not replenishable Depletion brings pumping to an endDepletion brings pumping to an end For more arid regions, loss of irrigation water means For more arid regions, loss of irrigation water means
end of agricultureend of agriculture
North China’s Plain’s water table, producing over North China’s Plain’s water table, producing over ½ of the country’s wheat and a 33% of corn, is ½ of the country’s wheat and a 33% of corn, is dropping 3 meters/yrdropping 3 meters/yr
Wheat farmers pump from a depth of 300 Wheat farmers pump from a depth of 300 meters, raising pumping costs so high that meters, raising pumping costs so high that farmers are forced to abandon irrigationfarmers are forced to abandon irrigation
Water Tables FallingWater Tables Falling ChinaChina
Mining underground water Mining underground water near the Hai, Yellow, and Huai near the Hai, Yellow, and Huai RiversRivers
Takes 1000 tons of water = 1 Takes 1000 tons of water = 1 ton of wheatton of wheat
40 million tons of wheat feeds 40 million tons of wheat feeds 120 million Chinese compared 120 million Chinese compared to 2 billionto 2 billion
IndiaIndia 100 million farmers drilled 21 100 million farmers drilled 21
million wells, investing $12 million wells, investing $12 billion in wells and pumpsbillion in wells and pumps
Electricity blackouts occur Electricity blackouts occur where ½ is used to pump where ½ is used to pump water from depths up to a kmwater from depths up to a km
Water Tables FallingWater Tables Falling
In southern India, In southern India, falling water tables falling water tables dried up 95% of wells dried up 95% of wells owned by small owned by small farmersfarmers
Irrigated land is Irrigated land is reduced by half over reduced by half over a decadea decade
Farmers are forced to Farmers are forced to return to dryland return to dryland farmingfarming
Water Tables FallingWater Tables Falling Some use modified oil-drilling Some use modified oil-drilling
technology to reach water, technology to reach water, going as deep as 1,000 going as deep as 1,000 metersmeters
15% of India’s food supply 15% of India’s food supply produced by mining produced by mining groundwatergroundwater
Texas, Oklahoma, and Texas, Oklahoma, and Kansas – 3 leading grain-Kansas – 3 leading grain-producing states – the producing states – the underground water table underground water table dropped by more than 30 dropped by more than 30 metersmeters
Water Tables FallingWater Tables FallingColorado RiverColorado River
Drawn by AZ, CA, Drawn by AZ, CA, CO, NV, NM, UT, WYCO, NV, NM, UT, WY
Irrigated area decline Irrigated area decline from 1997-2002from 1997-2002
CA and CO dropped CA and CO dropped 2% and 24% 2% and 24% respectivelyrespectively
Water Tables FallingWater Tables Falling IranIran
71 million people71 million people Overpumping aquifers by Overpumping aquifers by
an average of 5 billion an average of 5 billion tons of water/yr – 33% of tons of water/yr – 33% of its annual grain harvestits annual grain harvest
Water table is falling 2.8 Water table is falling 2.8 meters/yrmeters/yr
Saudi ArabiaSaudi Arabia 25 million people25 million people Water-poor as it is oil-richWater-poor as it is oil-rich Wheat harvest dropped Wheat harvest dropped
from 4.1 million tons in from 4.1 million tons in 1992 to 2.7 million tons in 1992 to 2.7 million tons in 2007, 34%2007, 34%
Water Tables FallingWater Tables Falling YemenYemen
22 million people22 million people Annual water extraction of Annual water extraction of
223 million tons exceeds 223 million tons exceeds annual recharge of 42 annual recharge of 42 million tons, water table million tons, water table dropping 6 meters/yrdropping 6 meters/yr
Grain production falling by Grain production falling by 2/3 over the last two 2/3 over the last two decadesdecades
Now imports 4/5 of its grain Now imports 4/5 of its grain supplysupply
Ranks 24Ranks 24thth of failing states of failing states
Water Tables FallingWater Tables Falling MexicoMexico
107 million people107 million people Demand of water is Demand of water is
outstripping supplyoutstripping supply Guanajuato – water table is Guanajuato – water table is
falling 2 meters or more a falling 2 meters or more a yearyear
Sonora farmers used to Sonora farmers used to pump water from the pump water from the Hermosillo aquifer at a depth Hermosillo aquifer at a depth of 35 ft. Now more than 400 of 35 ft. Now more than 400 ft.ft.
51% of the water extracted 51% of the water extracted from underground is from from underground is from aquifers being overpumpedaquifers being overpumped
Water Tables FallingWater Tables Falling
Overpumping of aquifers is happening in Overpumping of aquifers is happening in many countriesmany countries
Depletion of aquifers and the harvest Depletion of aquifers and the harvest cutbacks could be simultaneouscutbacks could be simultaneous
Depletion of aquifers = unmanageable Depletion of aquifers = unmanageable food scarcityfood scarcity
Rivers Running DryRivers Running Dry
Colorado RiverColorado RiverMajor River in the southwestern USMajor River in the southwestern US
Yellow RiverYellow RiverLargest river in northern ChinaLargest river in northern China
Nile RiverNile RiverLifeline of EgyptLifeline of Egypt
Indus RiverIndus RiverSupplies most of Pakistan’s irrigation waterSupplies most of Pakistan’s irrigation water
Rivers Running DryRivers Running Dry
Colorado RiverColorado RiverRarely makes it to Rarely makes it to
the seathe seaGoes through CO, Goes through CO,
UT, AZ, NV, and UT, AZ, NV, and CACA
Demand is Demand is destroying the destroying the river’s ecosystem, river’s ecosystem, including fisheriesincluding fisheries
Rivers Running DryRivers Running Dry
Yellow RiverYellow River Flows 4,000 km Flows 4,000 km
through 5 provinces through 5 provinces before it reaches the before it reaches the Yellow SeaYellow Sea
First ran dry in 1972 First ran dry in 1972 and since 1985 it has and since 1985 it has often failed to reach often failed to reach the seathe sea
Rivers Running DryRivers Running Dry Nile RiverNile River
Before the Aswan Before the Aswan Dam was built, 32 Dam was built, 32 billion cubic meters of billion cubic meters of water reached the water reached the Mediterranean each Mediterranean each yearyear
After the dam, After the dam, increasing irrigation, increasing irrigation, evaporation, and evaporation, and demands reduced its demands reduced its discharge to less discharge to less than 2 billion cubic than 2 billion cubic metersmeters
Rivers Running DryRivers Running Dry Indus RiverIndus River
Originating in the Originating in the Himalayas and goes into Himalayas and goes into Indian OceanIndian Ocean
Demand has made the Demand has made the river run dry in its lower river run dry in its lower reaches reaches
Population of 164 million, Population of 164 million, Pakistan ranks 12Pakistan ranks 12thth on the on the 2007 list of failing states2007 list of failing states
Allocating water among Allocating water among competing interests is part competing interests is part of an emerging politics of of an emerging politics of resource scarcityresource scarcity
Lakes DisappearingLakes Disappearing As river flows are As river flows are
reduced lakes have reduced lakes have been shrinking; Lake been shrinking; Lake Chad Central Africa, Chad Central Africa, the Aral Sea Central the Aral Sea Central Asia, and the Sea of Asia, and the Sea of GalileeGalilee
Most notable losses Most notable losses the Aral Sea cotton the Aral Sea cotton farming used up all the farming used up all the water which raised salt water which raised salt content and killed fishcontent and killed fish
China, Got Water?China, Got Water?
1,000 lakes have 1,000 lakes have disappeared over the past disappeared over the past 50 years 50 years
Average rate of 20 lakes Average rate of 20 lakes lost each yearlost each year
The government had set The government had set up 160 wetland protection up 160 wetland protection zones and invested heavily zones and invested heavily in measure to prevent in measure to prevent pollution pollution
How much is water in the Desert, How much is water in the Desert, an Economy lessonan Economy lesson
It takes 14 tons of water to make a ton of It takes 14 tons of water to make a ton of steal which sells for $560steal which sells for $560
It takes 1,000 tons of water to grow a ton It takes 1,000 tons of water to grow a ton of wheat which sells for $200of wheat which sells for $200
560/14 = $40 per ton of water560/14 = $40 per ton of water
200/1000 = $0.20 per ton of water200/1000 = $0.20 per ton of waterCities use more water than farming and Cities use more water than farming and
have a higher need for waterhave a higher need for water
Water LawWater Law
Riparian vs. Appropriation “First in time, first in Riparian vs. Appropriation “First in time, first in right” right”
Colorado water lawColorado water law Right to use, who has more right?Right to use, who has more right? Do cities have greater need than farmersDo cities have greater need than farmers Will water become the new oil when countries Will water become the new oil when countries
don’t produce their own, or have a food supplydon’t produce their own, or have a food supply International water wars?International water wars?
How much water is there, how much water How much water is there, how much water was there?was there?
Can we get more water?Can we get more water?Most water distputes are local and in high Most water distputes are local and in high
population areas, not worldwidepopulation areas, not worldwideOver population and standards of living, Over population and standards of living,
living on lessliving on less
Solutions or “The End”Solutions or “The End”