Cross-basin comparisons of water use, water scarcity and their impact on livelihoods: present and future

Larry Harrington, Simon Cook, Jacques Lemoalle, Mac Kirby, Clare Taylor and Jonathan Woolley

Outline

• CPWF BFPs introduced

• Basins described

• Comparisons made:

• Water use

• Water productivity

• Water and poverty

Niger

Basin Focal Projects

Questions for BFPs in basins

• To what extent is water truly scarce?

• To what extent is water scarcity a cause of poverty?

• Who gets access to water and who does not?

• How are such decisions made?

• How efficiently is water used in agriculture?

• How can it be used more efficiently?

• Which water-related interventions help improve food security,

livelihoods, and ecosystem services?

• What are the consequences (for different water users and uses at

different scales) of introducing different kinds of changes?

BFP work packages

• Water availability– Flows, balances, allocation, risks, scarcity

• Agricultural water productivity– “crop per drop”, spatial variability, how to improve

• Water, poverty and food security– How are water, poverty, food security and livelihoods interconnected?

• Institutional analysis– What are the institutional drivers of water and food issues and

solutions?

• Intervention analysis

– What are specific opportunities and risks for change? What are the

likely catchment- and basin-level consequences of introducing change?

Who wins and who loses?

BFP basins: size

BFP basins: population density

Basins: rainfall

Basins: per capita water supply

Basins: water uses

Basins that are “wet upstream” have different issues

than basins that are “wet downstream”

Mac Kirby

Devaraj de Condappa

Volta

Nile

wet wet

dry dry

Water productivity

• Value of products and

services (crops, livestock,

fisheries, ecosystem

services) per unit water

depleted

• Water depleted is that made

unavailable for reuse, e.g.,

through evaporation,

transpiration, contamination

or flow to a saline sink

Productivity measures

• Different kinds of productivity measures:

– Land productivity (yields)

– Labor productivity

– Water productivity

• Where land is scarce, people seek higher yields

• Where water is scarce, people seek higher water

productivity

Understanding spatial variability in water productivity

• It is often difficult to understand spatial variability in yields

– Soil fertility, salinity, flooding, biotic stress, unsuitable

timing of operations . . .

– Wealth of studies on yield gaps, yield constraints

• Why should it be any easier for water productivity?

– Need to study “water productivity” gaps, “water

productivity” constraints

Crop water

productivity in the

Volta –

. . . up to 0.2 kg/m3

Crop water

productivity in the

SFB –

. . . up to 0.5 kg/m3

Water productivity in rice – varies spatially and over

time: . . . up to 0.8 kg/m3

0.000

0.200

0.400

0.600

0.800

1990 1995 2000 2005

Year

Wate

r pro

ductivity, kg/m

3 Laos

Thailand

Cambodia

Vietnam

Vietnam Central

highlands

Vietnam Mekong

River Delta

crisis

response

WP

time0.000

0.200

0.400

0.600

0.800

1990 1995 2000 2005

Year

Wate

r pro

ductivity, kg/m

3 Laos

Thailand

Cambodia

Vietnam

Vietnam Central

highlands

Vietnam Mekong

River Delta

Water productivity in Karkheh [Iran] is higher

when animals are included

Measuring and improving livestock water productivity

Source: CPWFSource: CPWF

Measuring and improving livestock water productivity

Source: CPWFSource: CPWF

Ways to increase agricultural water productivity

• Maintain yields while using less water

– Aerobic rice

• Raise yields by using water that otherwise would be “lost”

– Input use

– Less evaporation, more transpiration

– In-field water harvesting

• Reallocate water from lower to higher value uses

– Across users in a basin or catchment

• Diversify farming systems

– Livestock

– Aquaculture

– High value crops

Ways to increase agricultural water productivity

Statement:

“ Efforts to improve water productivity should focus

on areas where water productivity is low”

• Not necessarily . . .

– Constraints ≠ opportunities

– It is often easier to increase crop yields in areas

where yields are already high

• the same may sometimes be true for water

productivity

Water and poverty or “water poverty?

– “BFPs have found that much more is known about the state of water on the one hand, and the state of food

security and poverty on the other, than is known

about how they interact and influence each other.”

Water and poverty or “water poverty?

Statement:

“ . . . Poverty is due to water scarcity”

• Not necessarily . . .

• Counter-examples

– Dry Punjab vs. wet Bangladesh

– Dry Egypt vs. wet Uganda

– Dry Sinaloa vs. wet Chiapas

Water and poverty or “water poverty?

Statement:

“ . . . Poverty is due to water scarcity”

• Not necessarily . . .

– Floods

– Water-related disease

– Water allocation among users

Factors other than water that affect rural poverty

• Farm size or access to land resources

• Off-farm employment and remittances from family members;

• Crop selection and yields

• Agroecosystem diversification including livestock

• Access to markets and credit

• Market and transport infrastructure and marketing margins;

• Education;

• Inheritance

• Expenses associated with starting a new family, or with life

transitions such as marriages

• Accidents or disease

Water and poverty or “water poverty?

Statement:

“ Improving water productivity is the best way to get

people out of poverty”

• Not necessarily . . .

– May be one element in an integrated strategy

– Need an historical context –

• The broad process of development and rural

transformation

• How can water-related interventions accelerate

this process?

Water and poverty or “water poverty?

• Karkheh:

– Poverty reduced by rural-urban migration, national poverty

reduction policies

• SFB:

– Poverty reduced by out-migration of smallholder farm families to

urban areas or to work on large commercial farms

• Mekong:

– Poverty reduced in

• Mekong delta – diversified production for markets

• Northeast Thailand – off-farm employment

– Poverty concentrated in “remote highlands”

• Volta: poverty varies inversely with rainfall

GNI vs Water

-10,000

0

10,000

20,000

30,000

40,000

50,000

-500 0 500 1000 1500 2000 2500

Water availability (m3/cap)

GN

I ($

/cap P

PP

)Water availability, poverty, and rural

transformation

Size of the circle is

proportional to the

share of agriculture

in GNI

Awkward conclusion

• Emphasize water-related interventions that help accelerate

– Rural transformation

– Equitable, dynamic development

– Employment generation

– (Without harming downstream communities)

• These may or may not be in water-scarce areas

• These may or may not be in areas with low water productivity

“You can do it; we can help”