Water resources are used in a lot of ways include agricultural irrigation, fisheries, hydropower, direct consumption, industrial production, recreation, navigation, environmental protection, the disposal and treatment of sewage, and industrial effluents. Water has sources and supplies, economic, social, and political characteristics which make it a unique and challenging natural resource to manage.
Water resources may also reference the current or potential value of the resource to the community and the environment. The maximum rate that water is potentially available for human use and management is often considered the best measure of the total water resources of a given region. Approximately 30 percent of the world’s fresh water is in liquid form and therefore potentially accessible for human use and management at any given time. The rest is either locked up in polar or glacial ice or water vapor. Of the 30 percent of fresh water in liquid form, almost all is held in groundwaters.
Water is a renewable resource since its continued flows are not affected by withdrawals or use. However, not all natural waters are renewable and renewable waters can become non-renewable by human actions such as contamination, watershed modification, or extraction in excess of inflow rate. Water is a vital resource for human and other animal and plant health.
Water is used in economic activities and hence must be allocated among competing uses. The commercial needs for water resources complicate matters, since water is a difficult to measure and identify. Water flows, evaporates, seeps and is transpired. This evasive nature entails that exclusive property rights are difficult to establish or enforce. As such it is difficult to subject water to market forces in a market economy. Furthermore water has a long-term value to the sustainability of life and economic activity, over periods that dwarf those considered in conventional cost-benefit analysis. The value of useable water to future generations is hard to quantify and define and requires considerations of quantity, quality, timing, and accessibility. As well, the value of water to particular uses depends crucially on its location, quality, and timing.
The above physical and economic characteristics of water make it a unique resource in which a degree of government involvement is inevitable. The discussion will now turn to the governance structures which have been implemented in order to manage and provide this complicated and vital resource.