7/29/2019 United Nations Water Under Pressure

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80km3 yr1

604 26 7

NorthernAmerica

SouthernAmerica

inc. Brazil

CentralAmerica andCaribbean

AMER ICAS

WORLDS THIRSTIESTJust three nations India, China and the United States together use about one-third of the roughly4,000 km3 of water extracted globally each year. In general, water demands in developed countries havebeen declining during the past 20 years, mostly as a result of more ecient use of water resources.

TOP 7GLOBAL WATER

CONSUMERS

1. INDIA 2. CHINA 3. UNITEDSTATES

4. RUSSIA 5. INDONESIA

3%

9%

4%

6. NIGERIA

3%

7. BRAZIL

3%

Rest ofworld

52

%

2%

4%

B Y N A T A S H A G I L B E R T

Water should be at the top of theagenda for the Earth Summit in Riode Janeiro, Brazil, in June, a United

Nations report urges.The fourth World Water Development Report

by the UN Educational, Scientific and CulturalOrganization (UNESCO), launched at theWorld Water Forum in Marseilles, France, on12 March, notes that industry, agriculture andbooming urban populations are putting Earthswater supplies under unprecedented pressure

(see graphic). Hundreds of millions of peopledo not have access to clean water, leaving themat risk from waterborne diseases. Withoutprompt action to improve water-managementpolicies, the report says, a global crisis looms.

Although the document contains a plethoraof facts and figures, its authors argue that a lackof reliable data on water quality and usagehas become a stumbling block for efforts tostrengthen policies and enforce regulations.You cannot properly manage something thatyou dont know about, says Olcay nver, coor-dinator of the UN World Water AssessmentProgramme. But closing the knowledge gapwill be expensive: building a gauging stationto measure a rivers flow can cost more thanUS$1 million, for example, and the expenseof ongoing operation can be difficult for poorcountries to justify. The report recommendsincreasing the use of remote-sensing technolo-gies to monitor water quality, but notes thatthese will never completely replace informa-tion gathered on the ground.

The report also focuses on the burgeon-ing demands of agriculture. Food productionalready consumes more than two-thirds ofthe worlds extracted water, and food demandis expected to rise by 70% by 2050, owing topopulation growth. Research into improving

crop yields and drought tolerance will helpnations to meet needs while using water moreefficiently.

The report concludes that policy-makersmust balance the requirements of agricultureand industry with the need for sustainablesources of clean drinking water by developingintegrated policies that satisfy all three sectors.Michel Jarraud, chairman of UN-Water agrouping of 28 UN organizations includingUNESCO says that the group will tell lead-ers at the Rio summit that the challenges, risksand uncertainties blocking the road to sustain-able development require a collective response

by the whole international community.

E N V I R O N M E N T

Water under pressureA UN analysis sets out global water-management concerns ahead of Earth Summit.

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7/29/2019 United Nations Water Under Pressure

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Use of improved drinking-water sources (%)

Nearly 1 billion people have no access to safe and improved water sources such as boreholes, protected wells, springs and rainwatercollections. More than 80% of the worlds waste water is not collected or treated, causing millions of deaths from waterborne diarrhoealdiseases every year in the developing world. Urban settlements are the main source of pollution, and the challenge will grow as theworlds urban population almost doubles to 6.3 billion by 2050.

91100%

Municipal

Industrial

Agricultural

7690%

5075%

Less than 50%

Insucient data

DYING FOR A DRINK

DRILLING DOWNCountries are increasingly meeting demand by extracting water from non-renewableunderground sources. Groundwater extraction has tripled in the past 50 years. Indiahas had the largest growth, jumping from less than 25 km3 in 1950 to 250 km3 in2010: about one-quarter of the global total (other countries shown for comparison).

300

250

200

150

Groundwaterextraction(km3p

er

year)

100

50

0

1950 1960 1970 1980 1990 2000 2010

India MexicoUSA China Iran

ON THE FARMAgriculture consumes almost 70% of all extracted water. Animal husbandry is themost water-intensive aspect of farming, and causes the greatest disparity in waterconsumption between the developed and developing worlds.The United States leads the world in per capita water use attributable to animalproducts, with each person consuming the equivalent of about 1,200 m3 per year.

Developed

Developing

Worldaverage

0 500 1,000 1,500

Cereals and starchy roots

Sugar and sweeteners

Oil crops and vegetable oils

Vegetables and fruits

Alcoholic beverages

Animal products

Water (m3 per capita per year)

224km3 yr1

2,526km3 yr1

364km3 yr1

27km3 yr1

3,942km3 yr1

95Northern

Africa

249Westernand centralEurope

5 EasternEuropeinc. Russia

29Sub-SaharanAfrica

677

East Asia

inc. China

64

Central

Asia

,004

South Asia

inc. India

27Australiaand NewZealand

0.08PacicIslands

AS IA

WORLDEUROPE

AFR ICA OCEANIA

Total withdrawalby sector

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