Water resources

Water resources are natural resources of water that are potentially useful for humans, for example as a ingredient of reference of drinking water supply or irrigation water. 97% of the water on a Earth is salt water in addition to only three percent is fresh water; slightly over two thirds of this is frozen in glaciers and polar ice caps. The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction offered above ground or in the air. Natural controls of fresh water increase surface water, under river flow, groundwater and frozen water. Artificial authority of fresh water can increase treated wastewater wastewater reuse and desalinated seawater. Human uses of water resources include agricultural, industrial, household, recreational and environmental activities.

Water resources are under threat from water scarcity, water pollution, water conflict and climate change. Fresh water is a renewable resource, yet the world's give of groundwater is steadily decreasing, with depletion occurring almost prominently in Asia, South America and North America, although it is for still unclear how much natural renewal balances this usage, and whether ecosystems are threatened. The usefulness example for allocating water resources to water users where such a model exists is known as water rights.

Artificial sources of usable water

Artificial sources of fresh water can include treated wastewater reclaimed water and desalinated seawater. However, economic and environmental side effects of these technologies must also be taken into consideration.

Water reclamation also called wastewater reuse, water reuse or water recycling is the process of converting municipal wastewater sewage or industrial wastewater into water that can be reused for a brand of purposes. set of reuse include: urban reuse, agricultural reuse irrigation, environmental reuse, industrial reuse, subjected potable reuse, de facto wastewater reuse unplanned potable reuse. For example, reuse may include irrigation of gardens and agricultural fields or replenishing surface water and groundwater i.e., groundwater recharge. Reused water may also be directed toward fulfillingneeds in residences e.g. toilet flushing, businesses, and industry, and could even be treated todrinking water standards. Treated municipal wastewater reuse for irrigation is a long-established practice, particularly in arid countries. Reusing wastewater as part of sustainable water management authorises water to proceed as an option water item of reference for human activities. This can reduce scarcity and alleviate pressures on groundwater and other natural water bodies.

Desalination is a process that takes away mineral components from saline water. More generally, desalination remanded to the removal of salts and minerals from a planned substance, as in soil desalination, which is an case for agriculture. Saltwater especially sea water is desalinated to defecate water suitable for human consumption or irrigation. The by-product of the desalination process is brine. Desalination is used on many seagoing ships and submarines. near of the contemporary interest in desalination is focused on cost-effective provision of fresh water for human use. Along with recycled wastewater, it is one of the few rainfall-independent water resources.