The report A Comprehensive Assessment of Water Management in Agriculture was published in 2007 by International Water Management Institute and Earthscan in an attempt to answer the question: how can water in agriculture be developed and managed to help end poverty and hunger, ensure environmentally sustainable practices, and find the right balance between food and environmental security? History Compiled after consultation with more than 700 individuals, numerous organisations and networks, it was the first critical evaluation of: the benefits, costs and impacts of the past 50 years of water development water management challenges facing communities today successful methods of managing water in farming around the world. The assessment confirmed that agriculture consumes more water resources than any other sector. A key finding was that a third of the world's population live in water-scarce areas. More than 1.2 billion live in areas of physical water scarcity, lacking water resources. Parts of Australia and the United States suffer in this way. A further 1.6 billion people live in areas of economic water scarcity, where there is insufficient human capacity or financial resources for people to effectively make use of water that is available. Here, sub-Saharan Africa is a good example; there is water in the rivers but no dams or pumps to enable people to use it. Trends affecting demands for water The report's authors forecast that the need for water would double within 50 years, due to global population rise, more people choosing to eat a diet of meat and vegetables rather than primarily consuming cereals, and climate change. Generally, about one litre of liquid water gets converted to water vapour to produce one calorie of food. We each consume between 2,000 and 5,000 liters of water every day, depending on our diet and how the food is produced. This is far more than the two to five litres we drink every day. A heavy meat diet requires much more than a vegetarian diet, because water is used to grow food for the animals as well as being used directly to support the livestock. Economic growth fuels changes in diets; for example, per capita meat demand in China has quadrupled over the last 30 years, and milk and egg products are becoming increasingly popular in India. Growing cities, expanding industry and biofuels are increasingly competing for water with an expanding agriculture. How feeding the future world will be possible The conclusion