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close this bookToward Sustainable Management of Water Resources (WB)
close this folderAcknowledgments
View the document(introduction...)
View the documentA new appreciation for water
View the documentFailure of current policies
View the documentFour principal failures
View the documentNew stresses require a new approach
View the documentA framework for improving the management of water resources
View the documentA comprehensive cross-sectoral approach
View the documentWater use per capita declined nearly 10 percent.
View the documentEnvironment and health

A new appreciation for water

Abundant as water may appear to be, we also have a new appreciation for how little freshwater is on the earth. Less than 3 percent of the world's water is freshwater, and most of this is in the ground, ice caps, and glaciers. Lakes and rivers account for only 0.014 percent of all water. Although enough precipitation falls each year on the land surface of the earth to cover the United States to a depth of 15 feet or to fill all lakes, rivers, and reservoirs fifty times over, about two-thirds of this evaporates back into the atmosphere, and more than half of what remains flows unused to the sea. Rainfall is also highly variable; the same area can experience droughts one year and floods the next. Withdrawals and the cost of recovery vary widely, as does the quality of water sources.

Indeed, water is critically scarce in many places. Generally, a country or region will experience periodic water stress when supplies fall below 1,700 cubic meters per person per year. The global average annual supply of renewable freshwater is about 7,400 cubic meters per person per year. However, twenty-two countries have renewable water resources of less than 1,000 cubic meters per person, and eighteen have more than 2,000. By and large Latin America is best endowed, while the Middle East and North Africa is where water is most scarce (table 1). By 2025, as many as fifty-two countries inhabited by some 3 billion people will be plagued by water stress or chronic water scarcity. India, now the world's second most populous country, will experience chronic water shortages nationwide. China will narrowly miss the water stress benchmark. However, in many areas of the country, such as the North China Plain, the demand for water is already outstripping supply.

Annual internal renewable water resources

Percentage of population living countries with scarce annual per capita resources

Region

Total (thousands of cubic meters)

Per capita (thousands of cubic meters)

Less than 1,000 cubic meters)

Between 1,000 and 2,000 cubic meters

Sub-Saharan Africa

3.8

7.1

8.0 0

16.0

East Asia and the Pacific

9.3

5.3

<1.0

6.0

South Asia

4.9

4.2

0.0

0.0

Eastern Europe and former U.S.S.R.

4.7

11.4

3.0

19.0

Other Europe

2.0

4.6

6.0

15.0

Middle East and North Africa

0.3

1.0

53.0

13.0

Latin America and the Caribbean

10.6

23.9

<1.0

4.0

Canada and the United States

5.4

19.4

0.0

0.0

World

40.9

7.7

4.0

8.0

Issues of scarcity have put water at the top of the international political agenda. Agreement on access to water is an important part of the peace accords between Israel and its neighbors. A water treaty has also helped to maintain peace between India and Pakistan. But water politics are not confined to historically conflicted or dry areas. Today, nearly 40 percent of the world's people live in more than 200 river basins that are shared by more than two countries. Even within countries, conflicts over water are often bitter. As populations and demand for limited supplies of water increase, interstate and international frictions over water can be expected to intensify.