Unless we change the way we use water, we could face a 40% gap by 2030 between global demand and what can sustainably be supplied if more people need more water. In the 20th century, while population grew by a factor of four, freshwater withdrawals grew by a factor of nine.Many countries are extracting groundwater faster than it can be replenished . Most of the world’s major rivers now hardly reach the ocean because of the extensive diversion of water for human use. Increasing water scarcity could cause annual grain losses equivalent to 30% of current world consumption (at the same time as the UN Food and Agriculture Organization says we will actually need 70% more food). As we grow wealthier, the more freshwater we need to supply cities, power plants and factories and to produce higher protein food such as dairy, meat and fish.Water for EnergyThe United States Geological Survey estimates that to produce and burn the 1 billion tonnes of coal the country uses each year, the mining and utility industries withdraw 55 to 75 trillion imperial gallons of water annually. That’s about the equivalent to all the water that pours over Niagara Falls in five months. The International Energy Agency forecasts that the world economy will demand at least 40% more energy by 2030 ; for non-OECD countries where the increase in energy demand will be highest, coal remains an important energy option.Water for FoodA kilogram of meat requires up to 20,000 litres of water to produce (compared with about 1,200 litres to produce a kilo of grain). Global demand for meat is forecast to increase 50% by 2025.
A Nexus of Water Challenges
This water-for-food vs water-for-energy dilemma the United States faces is similar to the “nexus” challenge which many fast-growing economies will have to tackle soon: how to simultaneously manage water for food, energy, people and the environment?
For example, as much of Asia becomes more urbanized and industrialized,more water will be directed towards energy and away from agriculture. Modelling undertaken for the World Economic Forum suggests that a 76% increase in water demand for energy and industry will be required across Asia by 2030 compared with today. This will occur at exactly the same time as these countries will need to almost double their food production. Against a baseline of 70% of water already being used for agriculture, how can these competing challenges be squared?
In addition, changing climatic conditions will accelerate freshwater security challenges. Unlike options in energy, there are no substitutes or alternatives to water. We will simply have to adapt. This is not only a problem for the poorest nations. Water security will affect people in Australia, the Balkans, California, China, India, Jordan, Greece, Mexico, North Africa, Pakistan, Saudi Arabia, Spain, South Africa and Turkey among others. In fact dryland areas represent more than 40% of the world’s surface area, covering over 100 countries.