Fresh water is a precious natural resource. Less than 2.5% of the world’s water is fresh water while the rest is seawater. In a nutshell, suppose Earth’s water is represented by 100 cups, only 2.5 cups are fresh water. But still, not all of the fresh water can be used. Among the fresh water resources in the world, a large part of it is the polar ice caps that have not yet melted. Therefore, less than 1% of the water mass is accessible by mankind in the form of fresh water.

Global Distribution of Water Resources

The geographical distribution of fresh water is highly uneven. Supply of clean and safe drinking water is a problem in many parts of the world. More than half of the world’s freshwater resources are contained in 9 countries (include Russia, China, India, Indonesia, Democratic Republic of the Congo, Brazil, Colombia, United States, Canada), as shown in the image. It is not difficult to imagine the scarcity of freshwater resources in other countries.

Global Water Demand

There is a global trend of raising water demand due to population and economic growth. According to The United Nations World Water Development Report 2018, the world population is expected to increase from 7.7 billion in 2017 to between 9.4 and 10.2 billion by 2050, and the global gross domestic product is expected to increase by 2.5 times in the same period. With the rapid population and economic growth, the report estimated that the global water demand will increase from about 4,600,000 mcm per year in 2017 by 20% - 30% to between 5,500,000 to 6,000,000 mcm per year by 2050.

Reference: United Nations World Water Development Report 2018