Each year, World Water Day highlights a specific aspect of freshwater. Under the theme ‘Water and Sustainable Development’, the year 2015 provides an important opportunity to consolidate and build upon the previous World Water Days to highlight water's role in the sustainable development agenda.
Water is at the core of sustainable development. Water resources, and the range of services they provide, underpin poverty reduction, economic growth and environmental sustainability. From food and energy security to human and environmental health, water contributes to improvements in social well-being and inclusive growth, affecting the livelihoods of billions.
Water is health
Water is essential to human health. The human body can last weeks without food, but only days without water. Water is essential to our survival. Despite impressive gains made over the last decade, 748 million people do not have access to an improved source of drinking water and 2.5 billion do not use an improved sanitation facility. Investments in water and sanitation services result in substantial economic gains.
Water is nature
Ecosystems – including, for example, forests, wetlands and grassland – lie at the heart of the global water cycle. All freshwater ultimately depends on the continued healthy functioning of ecosystems, and recognizing the water cycle is essential to achieving sustainable water management. Yet most economic models do not value the essential services provided by freshwater ecosystems. This leads to unsustainable use of water resources and ecosystem degradation.
Water is industry
Every manufactured product requires water. Some industries are more water-intense than others. 10 liters of water are used to make one sheet of paper, while 91 liters are used to make 500 grams of plastic.
Global water demand for manufacturing is expected to increase by 400% from 2000 to 2050, which is much larger than other sectors. The main increases will be in emerging economies and developing countries. Many large corporations have made considerable progress in evaluating and reducing their water use and that of their supply chains. Small and medium-sized enterprises (SMEs) are faced with similar water challenges on a smaller scale.
Technology and smart planning reduce the use of water, and can improve the quality of wastewater.
Water is energy
Water and energy are natural partners. Water is required to generate energy. Energy is required to deliver water.
Water is food
One liter of water is needed to irrigate one calorie food. Inefficient water use can mean 100 liters are used to produce one calorie. Irrigation takes up to 90% of water withdrawn in some developing countries. Globally, agriculture is the largest user of water, accounting for 70% of total withdrawal.
Many everyday foods require huge amounts of water for production.The current growth rates of agricultural demands on the world’s freshwater resources are unsustainable. Inefficient use of water for crop production depletes aquifers, reduces river flows, degrades wildlife habitats, and has caused salinization of 20% of the global irrigated land area. To increase efficiency in the use of water, agriculture can reduce water losses and, most importantly, increase crop productivity with respect to water.