CTA SeminarClosing the Knowledge Gap:

INTEGRATED WATER MANAGEMENT FOR SUSTAINABLE DEVELOPMENTBy Maimbo Mabanga Malesu

Strategies for Increasing Agricultural Water Productivity in Physically and Economically Water Scarce Region

Outline

• Problem Analysis• Understanding water scarcity, green and blue

water concepts• Tested approaches/tools in agric. Water mgt• Highlights on proven Technological

innovations• Conclusions

Location of ACP RegionThe ACP constitute 79 countries (48 African, 16 Caribbean and 15 Pacific) – falling in tropical and sub-tropical zones

Background for the ACP• Main objectives:

Sustainable development and poverty reduction within member states, as well as greater integration into the world's economy.

• Population in 2002 :

727 million (15% of developing countries). 94% of ACP pop in Africa, 5% in the Caribbean and 1% in the Pacific countries.

• Per capita GDP: US$ 100 - US$ 9000. Agriculture which is relied on for income and employment accounts for 16% of the GDP.

Major Challenges in ACP

1. Poor access to and availability of water in the region due to inadequate water harvesting infrastructure

2. In 2001, only 5% of ACP arable land was irrigated and 15% fertilizer used;

3. Increased prevalence of HIV/AIDS reduced labour availability & hence farm productivity.

4. Pop increase & Extremely low agricultural production – less than one tonne per hectare due to intra-seasonal dry spells and drought;

5. Poor management of rainwater – flooding, erosion, ecosystems pollution among others.

Agric. Water Management as a major entry point to livelihood enhancement

To exploit agric. potential in curbing hunger and undernourishment; technical, economic and human resources must be mobilized to facilitate water management through RWH & irrigation.

However, the ACP region faces physical and economic water scarcity denoting both availability and access quagmires and must institute strategies to address these challenges.

Global depiction of water scarcity

IWMI, 2009

Do we have adequate investments to cope with Water Scarcity?

How about at Community level?

The Policy Dilemma: Where do Governments target investments?

Can we boost per-capita water storage & Productivity in the ACP?

Technological considerations on Water Scarcity

• Bio-physical and socio-economic parameterization.• Assessment of rainwater partitions and their respective

quantification at regional, national, watershed and plot scale.

• Assessment of domestic, agricultural and environmental water needs/demands at national, watershed, homestead and farm scale.

• Identification and mapping of rainwater domains and respective technologies.

• Spatial based designs of appropriate rainwater technologies in respect to the technological mapping.

Understanding Rainwater Partitions is starting point for boosting water productivity

Water requirements for diets vs GDP(PPP) for year 2000

0

1

2

3

4

5

6

7

0 5000 10000 15000 20000 25000 30000 35000 40000

GDP(PPP) (US$/cap/y)

To

tal

die

tary

wat

er r

equ

irem

ents

(m

3/ca

p/d

ay)

0

500

1000

1500

2000

2500

To

tal

die

tary

wat

er r

equ

irem

ents

(m

3/ca

p/y

ear)

DEVD EA EURA

LAC NAF OECD

SA SEA SSAF

WA Sislands

JPN

USA

NOR

FRA

SWE

FIN

IRL

AUTISL

DNK

CHE

CAN

PYF

NCL

MNGURY

ARG

BHS

SYCKORSAU

KWT

THA

MYS

ISR

KGZ

LKA

IND

PAK

CHN

ALB

PRTHUN

BWA

BDI

COM

LBN

ZAF

MUS

ESTLVA

MKDMRT

MDA

KEN

Source: SEI 2006

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

Total Rainwater 1,400 2,424 3,824

Evapotranspiration 560 970 1,530

Runoff 443 785 1,229

Groundwater 108 582 690

Current Use 8 32 40

Pemba Unguja Zanzibar

Assessment of RWH in Zanzibar + LOBBYING(MDG Centre, 2007)

RW assessments: Case example for Sub-Saharan Africa

African countries in the ACP are the ones where rainfall exceeds 200mm/yr within SSA

RWH Domains (Mati et al, 2006)

Runoff Ephemeral rivers

Climate modeling –P/PET

Source: MINAGRI - 2010

Source: MINAGRI - 2010

MINAGRI - 2010

RWH System

Technology

Application

Soil and structural storage

- Zai pits - Cons. Tillage - Terraces - Level Bunds - Ditches - Drainage - SWC

Runoff Catchment Systems

In-situ RWH Systems

Check Dams Weirs Irrigations Canal Ponds – Lined / unlined Underground tanks Infiltration ditches Groundwater recharge Sand/Subsurface dams

Roof Catchment Systems

Ferro-cement tanks Masonry tanks Spherical tanks Underground tanks Recharge wells

Soil Storage Storage

GREEN WATER - Crop and Livestock production - Upgraded rain-fed farming - Agroforestry - Full and Supplementary irrigation

BLUE WATER - Domestic water - Groundwater recharge - Livestock production

Promising Water Harvesting Technological Options

INSITU RWH TECHNIQUES

Run

off

Run

off

Run

off

Run

off

Run

off

Run

off

Run

off

Run

off

Slope

Earthen Bunds

Zai-pits

Conservation Agric.

9 ponds/Km2 in Lare Kenya

Run-off Catchment Systems + Private Sector

By June 2010 RADA had constructed >400 X 120 m3 ponds in 10 districts of Rwanda

Best Practices Scaling Up Sites

CHECK DAMS + Surface irrigation in Zanzibar

Roof Catchment Systems + Drip Irrigation

Increased Awareness

India pioneers RWH, 2004

AFRICA: RWH could solve water shortages, 2006

Conclusions – Put Simple• We need to change the way we think - STOP

Blue water approaches to agric. water mgt. Think GREEN.

• Policy change backed with innovative technical planning, sound investment and monitoring.

• Support capacity building at all levels: Professional, technical and community.

• Increase Awareness: Spread the news through ICTs!!!!!

The World Agroforestry Centre

United Nations Avenue, Gigiri

P.O Box 30677 Nairobi, 00100, Kenya

Phone: +254 20 722 4000

Fax: +254 20 722 4001

Web: www.worldagroforestry.org Email: icraf@cgiar.org

THANK YOU – Green water is the way out