Arjen HoekstraUNESCO-IHE, Delft, Netherlands (www.ihe.nl)

The role of virtual water transfer in water management

North America

Central America

Western Europe

Eastern Europe

FSU

Central and South Asia

South east Asia

Oceania

Southern Africa

Central Africa

North Africa

South America

Middle East

-1141-307-300-90-9-4-31317204242377984No Data

Net virtual waterimport, Gm3

Virtual water content of products

1 kg grain 1-2 m3 water

1 kg cheese 5 m3 water

1 kg beef 16 m3 water

Five hundred 32-MB chips

(2 gram each)

16 m3 water

Definition of virtual water

Virtual water is the water ‘embodied’ in a product, not in real sense, but in virtual sense. It refers to the water needed for the production of the product.

Assessing virtual water trade flows

Virtual water content of a crop

Crop water requirement (m3/ha) / Crop yield (ton/ha)

Virtual water content of a livestock product1. Virtual water content of the live animal2. Distribute this volume over the different products from

this animal

Virtual water trade flows

Trade volume (ton/yr) Virtual water content (m3/ton)

Basic data

Global trade data

United Nations Statistics Division, New York

Virtual water content Crop water requirements (m3/ha): CROPWAT (FAO) Crop yields (ton/ha): FAOSTAT (FAO)

Virtual waterHistory of the concept

1993-94 Introduction of the concept by Tony Allan

12/2002 International Expert Meeting on Virtual Water Trade, UNESCO-IHE, Delft, Netherlands

03/2003 Session on ‘Virtual Water Trade and Geopolitics’ at the 3rd World Water Forum, Japan

Virtual waterState of current knowledge

Three global studies on virtual water trade.

Some national studies on virtual water trade (Middle East, North Africa, Southern Africa, Japan, China).

Knowledge on economic, environmental, social and cultural implications of current virtual water trade is nearly absent.

Knowledge on how to use virtual water trade as a means to relieve pressure on world’s water resourcesce is very weak.

Global virtual water tradebetween nations (1995-1999)

Volume

billion m3/yr

Percentage

%

Crops and crop products

Livestock and livestock products

Industrial products

695

245

100

67

23

10

Total 1040 100

[Hoekstra, 2003]

Global virtual water tradebetween nations (1995-1999)

Volume

billion m3/yr

Percentage

%

Crops and crop products

Livestock and livestock products

Industrial products

695

245

100

67

23

10

Total 1040 100

[Hoekstra, 2003]

30% wheat17% soybean15% rice 9% maize 7% raw sugar 5% barley

Global virtual water tradebetween nations (1995-1999)

Volume

billion m3/yr

Percentage

%

Crops and crop products

Livestock and livestock products

Industrial products

695

245

100

67

23

10

Total 1040 100

[Hoekstra, 2003]

34% bovine meat16% bovine hides

and leather12% cow milk &

milk products

10% swine and its products

8% live bovine 4% sheep and

its products

Global virtual water tradebetween nations (1995-1999)

Volume

billion m3/yr

Percentage

%

Crops and crop products

Livestock and livestock products

Industrial products

695

245

100

67

23

10

Total 1040 100

[Hoekstra, 2003]= 16% of global water use!

Drawing a national‘virtual water trade balance’

1. How much water goes into the country in the form of imported products?

2. How much water leaves the country in the form of exported products?

Virtual water balance of the USA

Net export of

virtual water:

164 Gm3/yr

0.0E+00

5.0E+10

1.0E+11

1.5E+11

2.0E+11

2.5E+11

1995 1996 1997 1998 1999

Export Import

Total water withdrawals USA:

500 Gm3/yr

Available water resources:

2500 Gm3/yr

= 1/15 of available resources

Virtual water balance of the Thailand

Net export of

virtual water:

46 Gm3/yr

0.0E+00

5.0E+10

1.0E+11

1.5E+11

2.0E+11

2.5E+11

1995 1996 1997 1998 1999

Export Import

Available water resources:

179 Gm3/yr

= 1/4 of available resources

Virtual water balance of the Japan

Net import of

virtual water:

82 Gm3/yr

0.0E+00

5.0E+10

1.0E+11

1.5E+11

2.0E+11

2.5E+11

1995 1996 1997 1998 1999

Export Import

Virtual water balance of the China

Net import of

virtual water:

19 Gm3/yr

0.0E+00

5.0E+10

1.0E+11

1.5E+11

2.0E+11

2.5E+11

1995 1996 1997 1998 1999

Export Import

Water withdrawal:

550 Gm3/yr

Water availability:

2800 Gm3/yr

Export virtual water 17

Import virtual water 34

1409Annual virtualwater budget

Water footprint of China 1392

60% green water

40% blue water

China Virtual water balance (Gm3/yr)

Withdrawal559

Green wateruse 816

Blue water 2812

Precipitation6152

2524 Evapotranspiration (ET) from non-agricultural area

6152Annual real

water budget

River discharge 2253

China Real water balance (Gm3/yr)

ET 3340

National virtual water trade balances 1995-1999

Net virtual water import, Gm3

-900 - -500-500 - -100-100 - -10-10 - 00 - 1010 - 5050 - 100100 - 500No Data

Net virtual water export Net virtual water importTop-7 list of countries Top-7 list of countries

Gm3/yr Gm3/yr

USA 164 Sri Lanka 84

Canada 64 Japan 82

Australia 58 Italy 31

Argentina 52 South Korea 30

Thailand 46 Netherlands 25

India 34 Indonesia 23

France 22 China 19

....... ......

Period: 1995-1999

Virtual water Virtual waterexporters importers

1. France 1. Italy

2. Ukraine 2. Netherlands

3. Ireland 3. Spain

..... 4. Germany

5. Russia

6. Belgium-Luxembourg

7. Portugal

......

Europe

Net export: 44% of Rhône runoff

Net import: 67% of Po runoffNet import: 36% of Rhine runoff

Virtual water trade balances of thirteen world regions (1995-1999)

North America

Central America

Western Europe

Eastern Europe

FSU

Central and South Asia

South east Asia

Oceania

Southern Africa

Central Africa

North Africa

South America

Middle East

-1141-307-300-90-9-4-31317204242377984No Data

Net virtual waterimport, Gm3

Arrows show trade flows >100 Gm3

Ranking of regions (1995-1999)

Gross virtual water import Gross virtual water export

Gm3 Gm3

Central-South Asia 1184 North America 1317

Western Europe 643 South America 415

North Africa 276 Oceania 363

Middle East 261 Southeast Asia 347

Southeast Asia 257 Western Europe 266

....... ......

the virtual water concept:what is the practical use?

1. Virtual water: an alternative source of water

Many national economies depend on (net) import of virtual water. For the period 1995-99:

Jordan 80% Italy 20%

Netherlands 80% Egypt 20%

Japan 40% South Africa 20%

Tunesia 50% China 4%

2. Virtual water trade: global water savings

Much of the international virtual water trade takes place from nations where water productivity is relatively high to nations where water productivity is relatively low.

global real water saving!

450 billion m3/yr saving due to global food trade= 8% of global water use for crop production!

[Oki et al., 2003]

3. Virtual water trade: an additional means to improve water use efficiency

Local water use efficiency

user level

Technology, water price, environmental awareness of the water user

Water allocation efficiency

national / basin level

Value of water in its alternative uses

Global water use efficiency

global level

Virtual water trade between water-scarce and water-abundant regions

4. Virtual water trade: an alternative to real interbasin water transfers

Proposed large inter-basin water transfers: China India South Africa Spain

Alternative: Trade of water intensive products from water-rich to

water-poor regions

5. Virtual water storage: an alternative for dams

[Renault, 2003]

0

1000

2000

3000

4000

5000

6000

7000

Global virtual waterstorage

Global capacity of realwater reservoirs

bil

lio

n m

3

living cattle

meat, oilsugar

grains

6. Calculation of national water footprints

m3/yr per capita

China, India, Indonesia 500

Mexico 1000

Netherlands, Belgium 2000

Conclusion

15-20% of the global water use is not used for domestic consumption but for export (in virtual form).

This is the global percentage; the situation strongly varies between countries.

The crude estimates show that it is very relevant to carry out virtual water analysis in any national or regional water policy study.

Future research agenda

Accounting Develop a common methodology and standards for virtual water accounting

Diets and footprints Understand the relation between consumption patterns, water needs, water scarcity and resulting virtual water trade

Trade Analyse current trade flows, trade relations and dependencies; and develop projections under global change scenarios

Application Enhance understanding of the implications of application of the virtual water concept on national and basin level

Political impacts Enhance understanding of virtual water trade on the position of sovereign nations and the political processes underlying decisonmaking

Awareness and debate Create a better understanding of consequences of conscious application

Thank you