Efficient water use tackles food insecurity

Without water, farmers cannot grow food. As food security issues increase, water resource management becomes more important. There is a need to increase the efficiency of water use in both irrigated and rainfed agriculture. At the same time, it is essential to limit the demand for food that requires a lot of water to produce.

Waterproductivity – the produce or value derived from each unit of water - must beincreased. It is estimated that an additional 5600 km³/year of water needs tobe made available by 2050 to eradicate malnutrition and feed an expectedincrease in world population of 3 billion world inhabitants. This is almostthree times the current global amount used for irrigation. However, this figurecouldchange depending on people’s changing diets; how much they consume, how much iswasted, what kind of food is demanded.

Currentagricultural practices often lead to the overuse of groundwater, water loggingof agricultural land, salinisation (increased salt concentrations) and the highuse of flowing water. The negative impacts of this approach are widespread. Decliningwater quality and supplies affect aquatic ecosystems and biodiversity, includingfisheries.

Researchfrom the Stockholm International Water Institute, Sweden, discusses how toincrease the amount of food production from each unit of water and land. Thereis potential for improvement in both rainfed and irrigated food productionsystems. Increasing water scarcity is often an issue of poor use of resources,rather than a lack of resources. There must be changes in water use practices toproduce more food per unit of water. These include:

• Giving people more secure water use rights andland tenure will improve water management in irrigated and rainfed systems.
• Developing appropriate tillage methods couldimprove soil quality; current methods often damage it.
• Rainwater harvesting and supplementary irrigation canreduce the impact of dry seasons.
• Improved management of existing irrigation systems,including investment in new irrigation and storage infrastructure, will reducewater wastage from these systems.
• There is a need for effective support services forrainfed farmers, particularly improved marketing skills, affordable credit systemsand improved extension services.

Toachieve this will require changes in governance, changes to the terms of agriculturaltrade, investment in human resources and changes to the way that land and waterresources are valued. Political commitment to improving the efficiency wateruse is necessary.

Theresearch recommends:

• Nationalstrategies for food and nutritional security should be established for allcountries. Alongside these, countries need policies and river basin targets forflows of water that maintain vital ecosystems functions, such as supportingfish stocks.
• Currentand proposed trade regimes need to be assessed based on their impacts on waterresources and ecosystems.
• Governmentsshould raise public awareness about the amounts of water needed to producedifferent kinds of food.
• Currentagricultural subsidies do not encourage efficient water use; these should be replacedby environmentally friendly subsidies, with rewards for efficient water management.
• Governmentsmust explore the possibility of establishing mechanisms to share the benefitsof water use amongst all people, not just farmers.
• TheUnited Nations must continue to pursue programmes that reduce the long-termvulnerability of communities and food systems to extreme weather events.
• Researchon food production should consider changes in consumer preferences, purchasingpower, the role of trade outlets and the food processing industry. If trends indiets continue in the same direction, there will be increasing pressure on theenvironment and public health.