In 2010 the United Nations General Assembly explicitly recognized the human right to water, before it already existed in international law through the human right to an adequate standard of living and the human right to health. The right to water means that water for everyone must be available in sufficient quantities, safe, of acceptable taste, odour and colour, physically accessible and affordable. Enough drinking water is is essential for maintaining some sort of basic health, but before that it is a necessity for survival. Human beings in warm climates cannot survive without water for longer than three or four days. For children under five waterborne diseases are a leading cause of death worldwide.
Every continent of the world is affected by water scarcity, making it a large global risk. Water in itself is not scarce, but the amount of usable freshwater for humans is less than 1% of all water on earth. Other problems are that water is very unequally distributed and the demand for freshwater has risen in recent times due to growing industry. Water scarcity can be physical or economic. Physical water scarcity means that there is are not enough water resources to meet demands. Around one fifth of the population currently live in areas affected by physical water scarcity. Economic water scarcity affects even more people, meaning that there are enough water resources available but that due to poor infrastructure or technology to draw water from rivers or other sources, demands for water cannot be met. This is a problem that is for example existing in large parts of Africa. The problem of water scarcity has been worsened by climate change and will get even more severe in the future.
For most people in developing countries the requirements defined by the UN are not met. In Asia and Africa the average distance women walk to a source of water is 6 kilometres, which is 6 times the distance that accordingly to the WHO people should have to walk in order for water to be physically accessible. Because of this people consume far less water than needed, as it is heavy and difficult to carry over such long distances. In some poor areas of the world, like the slums of Manila and Nairobi, water is even less affordable than in high-income cities.
It is not enough if freshwater is available, it has to be safe, too. That means water must be free from micro-organisms, chemicals and radiological hazards. If there are no safe sources of water in reach, people in developing countries resort to sources which are also used by animals, unprotected wells or other unsafe sources, resulting in a severe risk for their health and life. Together with poor sanitation, unclean water is the second biggest killer of children.
The question of water is not only an important one in developing countries. California is an example where there has been a struggle with the issue of water over a long time. As climate change continues, water scarcity could become a larger problem for developed countries, too. An example for this is North America, which gets a lot of water from glaciers that are in danger of disappearing due to climate change. In addition to that water privatization and liberalization is an issue worldwide, and thus also in Europe. Initiatives have been launched to ensure that water stays a public service and good for European citizens.
Ensuring the human right to safe water is a complex issue that affects a large population of the world and will continue to affect more and more people with the ongoing effects of climate change. But there is a lot that can be done to improve conditions for people around the globe. Advancing infrastructure and technology for accessibility of water, as well as ensuring safe drinking water through technologies that can detect contamination of water, are measures to be taken. Modern science also makes the conversion of saline water into portable water a possible measure.