Water trading is the process of buying and selling water access entitlements, also often called water rights. The terms of the trade can be either permanent or temporary, depending on the legal status of the water rights. Some of the western states of the United States, Chile, South Africa, Australia, Iran and Spain's Canary Islands have water trading schemes. Some consider Australia's to be the most sophisticated and effective in the world.[citation needed] Some other countries, especially in South Asia, also have informal water trading schemes. Water markets tend to be local and informal, as opposed to more formal schemes.[1]
Some economists argue that water trading can promote more efficient water allocation because a market based price acts as an incentive for users to allocate resources from low value activities to high value activities. There are debates about the extent to which water markets operate efficiently in practice, what the social and environmental outcomes of water trading schemes are, and the ethics of applying economic principles to a resource such as water.
In the United States, water trading takes on several forms that differ from project to project, and are dependent upon the history, geography, and other factors of the area. Water law in many western U.S. states is based in the doctrine of "prior appropriation," or "first in time, first in use." Economists argue that this has created inefficiency in the way water is allocated, especially as urban populations increase and in times of drought. Water markets are promoted as a way to correct these inefficiencies.
In addition to the supply of tap water, many local water resources are also being acquired by private companies, most notably Nestlé Waters with its numerous brands, in order to provide commodity for the bottled water industry. This industry – which often bottles common ground water and sells it as spring water – competes with local communities for access to their water supplies, and is accused of reselling the water at drastically higher prices compared to what citizens pay for tap water.[2][3][4][5][6][7][8][9][10][11][12][13]
Carey and Sunding 2001
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