Between 1970 and 1990 worldwide per capita water supplies decreased by a third, with population growth a major contributor to changes in patterns of water use. Population pressure coupled with the unequal distribution of water supply throughout the world, while impacting globally, has particular implications for continents:

• Asia supports 60.5% of the world’s population but has only 35.8% of the global water resources
• Europe has 13% of the world’s population and 8% of the world’s water resources
• Africa has 12.5% of the world’s population and 10.6% of the world’s water resources (Sub-Saharan Africa has the lowest level of access to safe water coverage of any region, with just 60% of the population having access)
• North and Central America has 8% of the population and 15.2% of the water
• Oceania has less than 0.5% of the world’s population but 4.8% of the world’s water resources
• South America has 5.5% of the world’s population and 25.6% of the world’s water resources

Projections by the United Nations suggests that given the current population and environmental degradation trends, by 2050 nearly 7 billion people in 60 countries will suffer from water scarcity. Other, more conservative projections predict a similar scenario with around 2 billion people in 48 countries experiencing water scarcity within the same timeframe. By 2025, it is predicted that the world will need an additional 17% more water to grow food for the increasing populations in developing countries and that total water use will increase by some 40%.