1

ClimDev-Africa

Agricultural Water Management in the Context of Climate Change

Tilahun Amede, Seleshi B. Awlachew, Bancy Matti, Seydou Traore, Muluneh Yitayew

First Climate Change and Development in Africa (CCDA-I) Conference

Addis Ababa, Ethiopia, 17-19 October 2011

2

CC IMPACTS: RAINFED AGRICULTURE

Climate variability will erode the resources base, and affect ecosystem services : Recurrent droughts & severe floods;

Droughts will decrease yields / productivity Floods may damage crops and infrastructure (irrigation, road) Complicate farm operations abd services; Fluctuations in farmers’ income: poor farmers may lack

means to buffer extreme years Impact on national economy, with 90% probability

3

IMPACTS: IRRIGATED AGRICULTURE

Glacier melt of water towers: temporary increase / decrease in water reserves;

Changes in groundwater recharge ;

Changes in timing and magnitude of river flows (irrigation schemes tapping directly from river, and storage requirements);

Temperature effects on water productivity: unproductive evaporation;

CO2 fertilization and irrigation productivity: unknown

4

“Over the past Gada, we have lost twomonths of rain. Now the rain is not coming at the right time: it is starting later and finishing before long. My daughter is now five years old and she has not seen a good harvest yet.”

Lars Naess, 2009

Annual water balance (A) and water withdrawal (B) of Africa and implications CC  

(UNEP, 2010) (UNEP, 2005)

6

Make Choices : Scenarios to 2050

Based on WaterSim analysis for the CA

Today

CA Scenario

Without productivity improvements

Policies for productivity gains, upgrading rainfed, revitalized irrigation, trade

7

Dependence on green and blue water 2000

Upgrade rainfed agriculture

Climate-smart Rainwater management systems (RWM)

• Integrated strategy that enables actors to systematically map, capture, store and efficiently use Green and Blue water in a landscape for productive and domestic purposes and ecosystem services.

• Decrease unproductive water losses;• Improve the water productivity (increase returns per

unit of water investment)• Capitalizes on harvesting principles, water productivity

at various scales; • Combining water management with land and

vegetation management. 8

9

Investing in Irrigation

Irrigated Area

Food price index

World Bank lending for irrigation

2.5

2.0

1.5

1.0

0.5

01960

1965

1970

1975

1980

1985

1990

1995

2000

2005

320

280

240

200

160

120

80

40

0

Dependency effect?

Investing in Irrigation

Reduce water loss for climate change adaptation

Canal type N

Average

flow rate

(l/s)

Loss

(l/s/100m)

% loss

per

100m*

% loss/

100m/30l/s

Main canal 121 43.21a 2.58a 6.46a 4.49b

Secondary canal 57 33.03b 1.59b 4.40b 4.00b

Field canal 49 2.88c 0.39c 2.49c 25.94a

11

Comparision of Per capita Storage Capacity

4 43746

1287 1406

2486

3255

4729

6150

0

1000

2000

3000

4000

5000

6000

7000

Kenya Ethiopia SouthAfrica

Thailand Laos China Brazil Australia NorthAmerica

Countries

Per

Capita

Sto

rage (

m^3

)

Increased Storage Capacity for CC adaptation; even without external support

12

Micro dose

Zai T

ub

er yie

ld

(t/h

a)

0

4

8

124050607080

Control With ZaiWithout Zai

Tu

be

r yie

ld

(t/h

a)

0123430

4050607080

Tu

be

r yie

ld

(t/h

a)

01234

1215182124

Farm A

Farm B

Farm C

Improve Livestock Systems for CC adaptation

Improve feed quality; reduce methane emissions

Integrate livestock into the wider development agenda (e.g. irrigation; watershed management);

Developing watering points in closer distances (> 35% milk yield);

Limit conversion of range to annual croplands;

Improve animal management (health, feed quality, productivity);

Interventions to maximize transpiration at the expense of evaporation (feed);

Incentives for adaptation (Value addition/ market opportunities) of livestock interventions

14

Convert unproductive water to productive use for CC adaptation

High unproductive water losses = Low system productivity;

Lenche Dima - all cropland

0

500

1000

1500

2000

2500

3000

evap

orat

ion

trans

pirat

ion runo

ff

deep

perc

olat

ion

flow

s pe

r HH

(m3)

livestock

crops

Kuhar Michael - all cropland

0

200

400

600

800

1000

1200

1400

1600

1800

evap

orat

ion

trans

pira

tion

runo

ff

deep

perc

olat

ion

flow

s pe

r HH

(m3)

livestock

crops

15

Building Adaptive capacity on local experiences .. • Building on byelaws/ religious

organizations/ Water User Associations

• Facilitate information flow / technologies using local channels

• Local institutions for collective action: Upstream-downstream

• Commitment from local authorities and policy makers

• Home gardens; women

16

Box 1: Majaluba for Rice Production in Shinyanga, Tanzania In Tanzania, farmers excavated

bunded basins, locally known as ‘majaluba’ which hold rainwater for supplemental irrigation of crops in ASAL regions;

About 35% of the rice in TZ is produced this way under smallholder farming Shinyanga, Dodoma, Tabora and the Lake Regions;

Majaluba utilize direct rainfall and runoff harvesting from external catchments;

Generally, rice yields are higher, attaining 3.43 t ha-1 with the use of harvested water for irrigation as compared to 2.17 t ha-1 ;

These systems have increased household incomes by 67%.;

Augment by other storage infrastructures

Box 2. Small scale irrigation in Ethiopia

SSI in four administrative regions of Ethiopia,

Crop yield under irrigation was higher by at least 35% compared to non-irrigated farms;

Benefits higher in farms where external inputs (fertilizer, improved seeds and pesticides) were used;

Farmers replaced low yielding varieties by high yielding maize cultivars;

Shifted towards diverse cropping, up to 10 new marketable crops;

The real challenge: improving irrigation efficiency, creating local capacity and collective action with local communities;

17

Key messages for CC adaptation:

1. Investing in water storage at landscape and higher scales (reservoirs, strategic dams, ground water etc..);

2. Policy geared towards climate-sensitive systems (Agriculture / wetlands / water towers) and vulnerable communities;

3. Cross-boundary hydrological planning /management; drought and flood monitoring and information system; coping strategies;

4. Improving rainwater management systems, from capturing to efficient utilization and resilience;

5. Responsive research system along with resources for innovation;

A CGIAR Challenge Programme Water for Food (CPWF) aims to increase water productivity and resilience of social and ecological systems

Tilahun AmedeCPWF Nile Basin Leadert.amede@cgiar.org

Thank you !