State of the World 2004

Boosting Water Productivity

Sandra Postel and Amy Vickers

Boosting Water Productivity

Overview:

1. A New Mindset for Managing Water

2. Water-Rich, Water-Poor

3. Water, Crops, and Diets

4. Cities and Homes

5. Industrial Water Use and Material Goods Consumption

6. Policy Priorities

Freshwater Ecosystems

• Rivers, lakes, wetlands, and underground aquifers

• They store, move, and cleanse water as it cycles between sea, air, and land

• Healthy ecosystems need

- Minimum quality and quantity of water

- Natural flow pattern

World Water Use

Agriculture (70%)

Industry (22%)

Towns and Municipalities

(8%)

Source: World Bank, World Development Indicators, 2001

Human Influences on Freshwater Ecosystems

• Water tables are falling from overpumping of groundwater

• Many streams and rivers run dry for portions of the year

• Large inland lakes are shrinking

• World’s freshwater wetlands have diminished in area by half

Current Water Use Patterns Are Unsustainable

• Impacts accelerate with increases in population and consumption

• Large-scale water development projects (i.e., dams, reservoirs, diversion projects) have social and ecological costs:

- Ecosystems destroyed

- Fisheries decimated- Aquatic species imperiled- People displaced from

their homes

1. A New Mindset for Managing Water

• Freshwater is a life support system for ecosystems

• Must allocate sufficient water throughout the year to protect valuable ecosystem functions

• Can use remaining water to satisfy human demands efficiently, equitably, and productively

Water Productivity of Selected Countries

Source: FAO, USGS, OECD

India

China

Russian Federation

United States

Brazil

Australia

Germany

Egypt

GDP per cubic meter of water use (2000 dollars)

2.8

3.6

8.5

12.3

18.0

20.3

21.3

40.2

Water Productivity: Value of economic goods and services per cubic meter of water extracted from the natural environment

2. Water-Rich, Water-Poor

• Water-poor areas have higher demands because crop production requires more

irrigation in drier climates

• Uneven distribution of water on a global scale

- 6 countries (Brazil, Russia, Canada, Indonesia, China, and Colombia) account for half of Earth’s freshwater supply

Estimated Annual Water Withdrawals Per Capita, Selected Countries (2000)

Cubic Meters Per Person Per Year

Ethiopia

Brazil

Russian Federation

India

Egypt

United States

42

348

527

640

1011

1932

Source: FAO, USGS

Affluence and Poverty

• Influence of power, politics, and money can override natural abundance or scarcity of water

Phoenix, Arizona: Desert climate, but imports water from Colorado River

Ethiopia: 84% of the Nile’s flow originates within its territory, but faces famine due to drought

1 out of 5 people in developing world (1.1 billion people) face risk of disease and death

due to lack of access to safe drinking water

Populations Lacking Access to Safe Drinking Water and Sanitation (2000)

Africa 36% 40%

Latin America & Caribbean 13% 22%

Asia 19% 53%

No Safe Drinking Water

No Adequate SanitationRegion

Source: World Health Organization

Meeting Basic Needs

• Urgent task: to provide all people with minimum amount of clean water needed for good health and sanitation

• More than enough water to accommodate everyone’s basic needs but political will and financial commitment lacking

• When private corporations manage water systems, cost-recovery can take priority over meeting basic needs

3. Water, Crops, and Diets

Must raise productivity of agricultural water use to meet growing food needs as water stress

deepens and spreads

Three Challenges:

• Delivering and applying water to crops more efficiently

• Increasing yields per liter of water consumed

• Shifting diets to satisfy nutritional needs with less water

Water, Crops, and Diets

• Surface water irrigation efficiency is typically poor (can be as low as 25-40%)

• Losses due to leaks, seepage, evaporation

Improving Irrigation Efficiency

Micro-irrigation methods

- drip and micro-sprinklers reduce volume of water applied to fields by 30-70% and increase crop yields by 20-90%

- using high-yielding and early-maturing crop varieties

- deficit irrigation: only watering plants during critical growth stages

Changes in cropping patterns and growing methods

Improving Irrigation Efficiency

Affordable technologies for small plots

- ex.: treadle pumps: human powered devices that give access

to shallow groundwater

- using ponds, check dams, and other structures to irrigate crops during dry season, recharge groundwater

Collecting and storing rainfall

Dietary Choices

0

1000

2000

3000

4000

5000

potatoes beans w heat rice poultry beef

Lite

rs o

f Wa

ter

potatoes beans wheat rice poultry beef

Water consumed to supply 10g of protein

Water consumed to supply 500 calories

67

89

132

421

135

219

204

251

303

1515

1000

4902

251

204

rice

4902

1000

beef

Based on California crop yields and water productivity. Source: Renault and Wallender (2000)

Dietary Choices

• Average U.S. diet, high in meat content, requires twice as much water as an equally nutritious vegetarian diet

• Cutting consumption of animal products in half would reduce:

- nation’s dietary requirements of water by 37%- incidence of heart disease - cruelty to animals- pollution of streams from industrial animal feedlots

4. Cities and Homes

• Waste is a major urban water management problem

• In many cities, water losses are 15% - 40%, some higher

• Unaccounted-for Water (UFW): volume of water withdrawn from nature but that never reaches an end-user, due to

- Leaky pipes and mains- Theft- Meter inaccuracies

Problems with Urban Water Losses

• Surrounding regions experience water stress: withdrawals outstripping available supplies

• When surplus water is extracted

• This “lost” water, if recovered, could help cities facing scarcity meet their water needs

• More energy required to pump, treat, and distribute excess water

- Rivers run dry- Habitats wither- Wildlife disappears

Household Water Use, Selected Cities and

Countries

0 200 400 600 800 1000

Kenya

United Kingdom

Waterloo, Canada

Sydney, Australia

Seattle, United States

Phoenix, United States

Liters Per Capita Per Day

47

149

218

255

281

832

Source: Thompson et al. (2001), National Water Demand Management Centre, Environment Agency, U.K. (2003), Gombos (2003), Water Services Association of Australia (2001), Mayer et al. (1999)

Household Water Use

Tips to reduce indoor household water consumption by almost 50%:

• Choose water-efficient appliances(clothes washers, dishwashers)

• Install water-efficient fixtures(toilets, showerheads, faucets)

Household Water Use

• Large domestic water demand for irrigation of lawns, landscapes, and golf courses

- 30 billion liters of water a day in the U.S.

• 45 million kg of fertilizers and chemicals used per year

• Excess fertilizers and chemicals run off into streams, seep into groundwater

- contaminating drinking water- polluting lakes and ponds

Household Water Use

To reduce outdoor water consumption…

• Use more efficient sprinklers and irrigation systems

• Choose natural landscaping and native plants - drought-adaptive grasses, groundcovers, wildflowers

and plants that thrive naturally in local climate

5. Industrial Water Use and Material Goods Consumption

• Major water-using industries:Thermal electric powerIron and steelPulp and paperChemicalsPetroleumMachinery manufacture

• Water is used for cooling, washing, processing, heating

• In developing countries, pollutant loads rising along with industrial water demand

Industrial Water Use and Material Goods Consumption

Incentives for increasing efficiency of water use in industrial facilities: • Cost savings

• Need to comply with permit requirements

• Advances in technologies that allow process water to be reused and recycled

• Availability of low-cost reclaimed nonpotable water

How Individuals Can Reduce Their Impacts on Freshwater

1. Purchase fewer material goods

2. Eat a nutritious, less meat-intensive diet

3. Select native plants and grasses for landscapes, rely on natural rainfall

How Individuals Can Reduce Their Impacts on Freshwater

4. Install water-efficient appliances and fixtures

5. Support local land use ordinances that protect wetlands, aquifers, and watersheds

6. Serve on local water management boards to monitor and enforce water protection strategies

6. Policy Priorities: Government Action

1. Protect public trust in water

2. Institute or strengthen groundwater regulations to promote sustainable use

3. Implement tiered water pricing to encourage conservation: unit price of water increases along with consumption

Policy Priorities: Government Action

4. Restrict water use during seasonal lows

5. Encourage water trading between willing sellers and buyers to reallocate available supply

About the Authors“Boosting Water Productivity”

by Sandra Postel and Amy Vickers

 Sandra Postel is co-author of Rivers for Life: Managing Water for People and Nature (Island Press, 2003), and director of the Global Water Policy Project in

Amherst, MA. More at www.globalwaterpolicy.org

 Amy Vickers, author of the award-winning Handbook of Water Use and Conservation: Homes, Businesses, Landscapes, Industries, Farms (WaterPlow Press) is an engineer and water conservation specialist based in

Amherst, MA. More at www.waterplowpress.com

More information on State of the World 2004

at www.worldwatch.org