Facts about Freshwater

Water is desalinated to obtain freshwater suitable for animal consumption or irrigation, or, if almost all of the salt is removed, for human consumption.

Freshwater is a term for water that has no appreciable salinity; that is, a low salt concentration.

Freshwater is an important renewable resource, necessary for the survival of most terrestrial organism, and is required by humans for drinking and agriculture, among many other uses.

Only three percent of the water on Earth is freshwater in nature, and about two-thirds of this is frozen in glaciers and polar ice caps.

Freshwater bodies include lakes and ponds, rivers, some bodies of underground water and many kinds of man-made freshwater bodies, such as canals, ditches, and reservoirs.

Freshwater is variously defined and there is not an authoritative standard.

In areas with no freshwater on the ground surface, freshwater derived from precipitation may, because of its lower density, overlie saline ground water in lenses or layers.

Freshwater bodies of water, such as ponds, lakes, rivers, and streams, contain low concentrations of dissolved salts and other total dissolved solids.

Access to unpolluted freshwater is a critical issue for the survival of many species, including humans, who must drink freshwater in order to survive.

Freshwater creates a hypotonic environment for aquatic organisms.

The University Cooperation for Atmospheric Research (UCAR) defines freshwater as less than 1,000 parts per million (1 part per thousand).

Freshwater lakes, most notably Lake Baikal in Russia and the Great Lakes in North America, contain seven-eighths of this fresh surface water.

Most of the modern interest in desalination is focused on developing cost-effective ways of providing freshwater for human use in regions where the availability of water is limited.

Some protists accomplish this using contractile vacuoles, while freshwater fish excrete excess water via the kidney.