Water conflict or water war is a term describing a conflict between countries, states, or groups over the rights to access water resources. The United Nations recognizes that water disputes result from opposing interests of water users, public or private. A wide range of water conflicts appear throughout history, though rarely are traditional wars waged over water alone. Instead, water has long been a source of tension and one of the causes for conflicts. Water conflicts arise for several reasons, including territorial disputes, a fight for resources, and strategic advantage.
Water conflicts can occur on the intrastate and interstate levels. Interstate conflicts occur between two or more neighboring countries that share a transboundary water source, such as a river, sea, or groundwater basin. For example, the Middle East has only 1% of the world's fresh water shared among 5% of the world's population. Intrastate conflicts take place between two or more parties in the same country. An example would be the conflicts between farmers and industry (agricultural vs industrial use of water).
These conflicts occur over both fresh water and salt water, and both between and within nations. Conflicts occur mostly over freshwater; because freshwater resources are necessary, yet scarce, they are the center of water disputes arising out of need for potable water, irrigation and electricity generation. As freshwater is a vital, yet unevenly distributed natural resource, its availability often impacts the living and economic conditions of a country or region. The lack of cost-effective water supply options in areas like the Middle East, among other elements of water crises can put severe pressures on all water users, whether corporate, government, or individual, leading to tension, and possibly aggression.
There is a growing number of water conflicts that go unresolved, largely at the sub-national level, and these will become more dangerous as water becomes more scarce, climate changes alter local hydrology, and global population increases.