Home > IWMI's Presentation to the 4th World Water Forum
A Parched Planet ? : Beyond more Crop Per Drop
Poor
access to reliable, safe and affordable water for food and livelihoods
is a poverty trap for 70% of the world’s
poor people- the 800 million poor people that live mainly in
rural Africa and Asia.
On March 20th, the thematic day on Water,
Food and Environment at the 4th World Water Forum in Mexico (www.worldwaterforum4.org.mx),
participants debated on “Beyond More Crop Per drop” (www.iwmi.cgiar.org/wwf4),
the theme document released by IWMI with 9 partner organizations
.
“It takes about seventy times more water to grow the food
we eat every day than we need for drinking, cooking, bathing and
other domestic needs,” says Frank Rijsberman, Director General
of the International Water Management Institute (IWMI), “as
much as 2,000 liters of water to grow 1 kilo of rice and 11,000
liters for a single quarter pounder hamburger”. Many rivers
in the arid and semi-arid regions of the world no longer reach
the sea. These river basins are closed or closing, with all the
water used before it reaches the mouth of the river. Developing
water resources in closed basins is robbing Peter to pay Paul.
According to David Molden, Leader of
the Comprehensive Assessment of Water in Agriculture, “ “Meeting the Millennium
Development Goals on reducing poverty and hunger, together with
increasing trends in food consumption, imply a doubling in the
demand for food by 2050, and without improvements in water productivity
the demand for water in agriculture also doubles.” Doubling
the demand for water in agriculture would lead to widespread water
scarcity for the large majority of the rural poor.
Water productivity for a rice farmer
is the amount of rice produced for every unit of water consumed
in the process; the crop per drop. Increasing water productivity
implies getting more crop per drop. But if a farmer has not only
a rice field but also a fish pond, then the total water productivity
combines the amount of rice and fish produced per unit of water
consumed. At the river basin level, water productivity needs to
be defined beyond more crop per drop, including crop, livestock
and fishery yields, ecosystem services as well as social impacts
such as on health.
The rapidly expanding requirements of
water for food production, both in rainfed and irrigated agriculture,
have entailed very large water withdrawals, significant modification
of flow regimes, and degradation of water quality—all with major implications
for ecosystem health. The challenge, therefore, for water
management for food and environment lies in finding water for expanding
cities, often taken from agriculture; growing food for a growing
population; providing jobs for rural poor while sustaining the
environment.
Blue and Green Water
The myopic focus of water resources
management on blue water alone needs to be replaced by an approach
to manage the complete water cycle, including both green and blue
water, is one of the key messages of “Beyond More Crop Per Drop”. Traditionally,
what is defined as renewable water resources is only that share
of rainfall that runs of into rivers or recharges the groundwater – this
is only 40% of total rainfall – we call this blue water.
Sixty percent of all rainfall never reaches a river or groundwater
aquifer; it replenishes the soil moisture and evaporates from
the soil or is transpired by plants – we call this the
green water.
Green water cannot be piped or drunk, and is therefore safely
ignored by urban water managers. But green water is crucial to
plants, both in ecosystems and in agriculture, and needs to be
managed carefully. Water managers need to manage the complete water
cycle and account for the complete spectrum of management options
from pure rainfed, to rainwater harvesting, supplemental irrigation,
to full irrigation.
For most
regions of the world, increasing water productivity in agriculture,
rather than allocating more water, holds the greatest potential
to improve food security and reduce poverty at the lowest environment
cost. Low productivity rainfed agriculture requires 4000 liters
of water to produce a kilogram of cereals, often coarse grains
such as sorghum or millet. Irrigation systems in Africa and Asia
typically require 2000 liters of water to produce a kilogram of
rice or wheat. In the best irrigation systems it takes only 500
liters. That is the promise and the challenge.
How can it be done? Some key examples (for
more see www.iwmi.cgiar.org/wwf4):
- enhancing the safe and productive use of wastewater in agriculture:
making an asset out of wastewater;
- multiple use systems: single
water systems for domestic use, agriculture,
aquaculture, agroforestry
and livestock; and
- supplemental and micro-irrigation: small-scale,
low-cost technology that provides
an entry level for poor people.
Water action cannot be successful on its own, rather it needs
to be incorporated into an overall sustainable development approach
that aims to achieve all Millennium Development Goals, not just
the water and sanitation target. Vice versa, few Millennium Development
Goals can be achieved without progress in the water sector. For
achieving the hunger and poverty targets in rural areas, addressing
the availability of water for food and livelihoods for poor people
is crucial.
“Business as usual is not an option.
Increasing the productivity of water is a top priority for agricultural
research. Improving water productivity by 40% on rainfed and irrigated
lands could reduce the need for additional water for irrigation
to zero.”
Frank Rijsberman
“Providing water for food makes
the difference between poverty and prosperity for the rural poor,
70% of the 800 million poor rural people today depend on water
in one way or the other - to grow crops, for fishing, or jobs
in agricultural processing”
David Molden
“The value of water in agriculture
is measured in cents while the value of water for domestic use
or industry is measured in dollars. The consequence is that urban
people out-compete farmers for water everywhere, and water is
moving out of agriculture to satisfy the rapidly growing urban
and industrial demand in developing countries.”
Frank Rijsberman
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