The combined vicious impact of poverty, rising demand for food and insufficient availability of water therefore poses a serious challenge for world food security and universal access to clean water. One billion people are deprived of clean water, and most of these people are also hungry. They live in rural areas and agriculture is their main source of income.
How are we to ensure water availability and food security, while safeguarding the environment? At present, more than one-third of the world s food production comes from the irrigated areas that make up 16 percent of the planet s arable land. Irrigated farming is at least twice as productive as rainfed farming3, and during the next 30 years some 70 percent of additional food production in developing countries should come from irrigated land.
It is urgent to avoid poor irrigation practices that have often led to diminishing water supplies, land degradation and spread of disease . Far too often, more water is being pumped than can possibly be recharged. Also , too much water is being lost along canals, because of leakage , wastage , seepage or evaporation. Too many schemes are losing productivity because of inappropriate drainage, waterlogging and a build-up of salts in the soil.
We thus have to turn increasingly to adopt integrated watershed management, curb the upstream deforestation that generates flooding and erosion, and significantly increase investment in water control infrastructure. Finally, water use will be sustainable only if it is done in a socially equitable manner.
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