Portal:Water - Wikipedia
The Water Portal
![The multiple arches of the Pont du Gard in Roman Gaul (modern-day southern France). The upper tier encloses an aqueduct that carried water to Nimes in Roman times; its lower tier was expanded in the 1740s to carry a wide road across the river.](https://upload.wikimedia.org/wikipedia/commons/thumb/4/42/Pont_du_Gard_BLS.jpg/300px-Pont_du_Gard_BLS.jpg)
![](https://upload.wikimedia.org/wikipedia/commons/thumb/a/ae/Drinking_water.jpg/140px-Drinking_water.jpg)
Water is an inorganic compound with the chemical formula H2O. It is a transparent, tasteless, odorless, and nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent). It is vital for all known forms of life, despite not providing food energy or organic micronutrients. Its chemical formula, H2O, indicates that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. The hydrogen atoms are attached to the oxygen atom at an angle of 104.45°. In liquid form, H2O is also called "water" at standard temperature and pressure.
Because Earth's environment is relatively close to water's triple point, water exists on Earth as a solid, a liquid, and a gas. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds consist of suspended droplets of water and ice, its solid state. When finely divided, crystalline ice may precipitate in the form of snow. The gaseous state of water is steam or water vapor.
Water covers about 71% of the Earth's surface, with seas and oceans making up most of the water volume (about 96.5%). Small portions of water occur as groundwater (1.7%), in the glaciers and the ice caps of Antarctica and Greenland (1.7%), and in the air as vapor, clouds (consisting of ice and liquid water suspended in air), and precipitation (0.001%). Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea. (Full article...)
![](https://upload.wikimedia.org/wikipedia/commons/thumb/4/44/Nuvola_apps_filetypes.svg/47px-Nuvola_apps_filetypes.svg.png)
- ... that American artist Inez Demonet created watercolors of facial injuries for the War Department?
- ... that although Kississing Lake is threatened by water contaminated with tailings, it is the main resource for nearby residents?
- ... that there wasn't enough water in Oceanside to build more than half of the E. F. Barrett Power Station?
- ... that the Santa Ynez Reservoir in Pacific Palisades, which was built to provide water for firefighting, was empty when the 2025 Palisades Fire began?
- ... that It Was Hot, We Stayed in the Water explores the theme of water and was inspired by Phil Elverum's visits to the ocean?
- ... that compositions by Graham Waterhouse range from the beginning of his String Sextet, Op. 1, in 1979 to the Fantasia Ucraina for two violins in 2022?
![DYK Question Mark](https://upload.wikimedia.org/wikipedia/commons/thumb/4/44/Nuvola_apps_filetypes.svg/55px-Nuvola_apps_filetypes.svg.png)
- ...that total dissolved solids, a class of water pollutants, is useful as an indicator of aquatic biota health, yet harmful to the plumbing of aquaria and hot tubs?
- ...that a Navy shower is a method of showering that conserves both water and energy?
Water News
Note: this section was updated in February 2020
- Water topic page – from NASA
- The World Water Assessment Programme – monitors freshwater issues and provides recommendations
- Water Security – from UNESCO
- Dundee UNESCO Centre – a portal for Water Law, Policy and Science from the University of Dundee
- The Water Network – knowledge platform for water professionals to connect share knowledge
- Watermonitor.gov – a portal to U.S. federal water information
- Water Topics – from the U.S. EPA
- Watershed News – from EPA
- U.S. Department of Agriculture Water News – USDA
- National Rural Water Association – NRWA news and press releases
- India Water Portal – community-contributed water resources, articles, news, Q&A, data, events, opportunities, photos and videos.
- Alberta WaterPortal – water news, info, events, and community
- The New York Times Water topic page
- The Guardian Water topic page
- The 2005 Preliminary Report of the Sustainable Water Resources Roundtable – Advisory Committee on Water Information (inactive as of December 5, 2019)
Selected picture
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A side-by-side comparison of the Aral Sea in 1989 and 2008, showing its severe shrinkage owing to poor water resource management. The Aral Sea was once the fourth-largest lake in the world. However, the rivers that fed it were diverted by Soviet-era irrigation projects. It had shrunk to 10% of its former size by 2007, and is still shrinking. The near-loss of the Aral Sea, which is now in Kazakhstan and Uzbekistan, has been considered one of the planet's most disastrous examples of poor environmental resource management.
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An iceberg is a large piece of freshwater ice that has broken off a glacier or an ice shelf and is floating freely in the open sea. Because the sea around this iceberg is so calm, the underwater portion is visible through the clear water. The largest iceberg ever detected was B-15, which split from the Ross Ice Shelf in Antarctica in 2000, and had a flat top; it had a surface area of 11,000 km2 (4,200 sq mi) and broke into several pieces in 2002 and 2003. This picture depicts an irregularly shaped iceberg with a rounded top, calved from a glacier in the Arctic and photographed in the Arctic Ocean north of Svalbard.
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Rain over Beinn Eich, Luss Hills, Scotland
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Breaking waves at Porto Covo, Portugal
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Waves on rocks at sunset in Sète, France
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An example of guttation, the appearance of drops of xylem sap on the tips or edges of leaves of some vascular plants, on an Equisetum. At night, transpiration usually does not occur because most plants have their stomata closed. When there is a high soil moisture level, water will enter plant roots, because the water potential of the roots is lower than in the soil solution. The water will accumulate in the plant creating a slight root pressure. The root pressure forces some water to exude through special leaf tip or edge structures, hydathodes, forming drops. Guttation is not to be confused with dew, which condenses from the atmosphere onto the plant surface.
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A wastewater treatment plant in Cuxhaven, Germany. Wastewater treatment is a process used to remove contaminants from wastewater or sewage and convert it into an effluent that can be returned to the water cycle with acceptable impact on the environment, or reused for various purposes (called water reclamation)
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Morning mist on Lake Mapourika, a lake on the West Coast of New Zealand's South Island. It is the largest of the west coast lakes, a glacier formation from the last ice age. It is filled with fresh rain water which runs through the surrounding forest floor, collecting tannins and giving it its dark colour.
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The head of an impact sprinkler, a type of irrigation sprinkler in which the sprinkler head, driven in a circular motion by the force of the outgoing water, pivots on a bearing on top of its threaded attachment nut. Invented in 1935 by Orton Englehardt, it quickly found widespread use.
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An animated image showing the long-term mean monthly precipitation around the world. Precipitation occurs when a local portion of the atmosphere becomes saturated with water vapor and condenses, forming rain drops or ice crystals within a cloud via collision that then fall to the surface, except for virga, which evaporates while in the air.
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Rain is an oil-on-canvas painting by Dutch painter Vincent van Gogh, part of The Wheat Field, a series that he executed in 1889 while a voluntary patient in the Saint-Paul asylum near Saint-Rémy-de-Provence, France. Through his cell window on the upper floor, he could see an enclosed wheat field, and he made about a dozen paintings of it over the changing seasons. In this work, he represented falling rain with diagonal lines of paint. The style is reminiscent of Japanese prints, but the effect is stylistically personal to Van Gogh. Seen through his rain-splattered window, he shows its bleak aspect in November, with grey clouds overhead and the wheat already harvested. The painting is now in the collection of the Philadelphia Museum of Art.
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Photograph: José Manuel Suárez
When a liquid drop impacts the surface of a liquid reservoir it can float, bounce, coalesce with the reservoir, or splash. A floating drop remains on the surface for several seconds. Drop bouncing can occur on perturbed liquid surfaces. If the drop is able to rupture the thin film of gas which separates it from the liquid reservoir, it can coalesce. Additionally, higher Weber number drop impacts produce splashing. In the splashing regime, the impacting drop creates a crater in the fluid surface, followed by a crown around the crater. Finally, a central jet, called the "Rayleigh jet" or "Worthington jet", protrudes from the center of the crater. If the impact energy is high enough, the jet rises to the point where it pinches off, sending one or more droplets upward out of the surface.
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Waterfall Shypit (height 14 m), Mizhhiria Raion, Zakarpattia Oblast of western Ukraine
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Worm Bay at Port Campbell National Park, Peterborough, Victoria, Australia
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Surface irrigation system using siphon tubes
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The Haditha Dam is an earth-filled dam in Iraq, holding back the waters of the Euphrates to create Lake Qadisiyah. The area around Haditha is very arid, with a hot desert climate; the annual precipitation is about 127 millimetres (5 in), mainly occurring during the winter. This photograph, taken from the International Space Station in November 2015, shows the reservoir at a low water level, surrounded by an expanse of dry lakebed; the Haditha Dam is visible near the top of the image. Lake Qadisiyah has a maximum water-storage capacity of 8.3 cubic kilometres (2.0 cu mi) and a maximum surface area of 500 square kilometres (190 sq mi). The associated hydroelectric power station is capable of generating 660 megawatts of electricity, and outlets at the foot of the dam can discharge 3,000 cubic metres (110,000 cu ft) of water per second for irrigation.
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A fire hydrant in Alkmaar, the Netherlands. Fire hydrants are a source of water provided by most metropolitan communities to enable firefighters to tap into the municipal water supply to assist in extinguishing a fire.
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Plate XIX of "Studies among the Snow Crystals ... " by Wilson Bentley (1902), the first person known to photograph snowflakes. He did so by catching an individual snowflake on a blackboard, rushing it onto some black velvet, which he would then photograph using a bellows camera he had attached to a microscope. His first photograph of a snowflake was on January 15, 1885 and he would capture over 5000 images of crystals in his lifetime. Bentley also photographed all forms of ice and natural water formations including clouds and fog. He was the first American to record raindrop sizes and was one of the first cloud physicists.
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A view of the Rosoki River in the eponymous village, Macedonia
Categories
Photo gallery links
(updated in February 2020)
- World Water Crisis - Photo essays – from Time
- Water Science Photo Galleries – from United States Geological Survey (USGS)
- Surface Water Photo Gallery – from USGS
- Ocean Images – from the National Ocean Service, NOAA
- FAO Aquaculture Photo Library – from the Food and Agriculture Organization of the United Nations
- Oceans and Water – images and videos from The Exploratorium
- The world's threatened rivers - in pictures – from The Guardian
- Channeling Earth: Rivers Seen From Space – from Wired
- Image Gallery and Video Gallery – California water-related images and various water-related videos from the Water Education Foundation
- Celebrate AZ Water Photo Gallery – Arizona water-related images, from Water Use It Wisely
Topics
General images
The following are images from various water-related articles on Wikipedia.
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Presence of colloidal calcium carbonate from high concentrations of dissolved lime turns the water of Havasu Falls turquoise. (from Properties of water)
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Rain water flux from a canopy. Among the forces that govern drop formation: Surface tension, cohesion, Van der Waals force, Plateau–Rayleigh instability. (from Properties of water)
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Rain falling over a drainage basin in Scotland. Understanding the cycling of water into, through, and out of catchments is a key element of hydrology. (from Hydrology)
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Mortality rate attributable to unsafe water, sanitation, and hygiene (WASH) (from Drinking water)
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Total renewable water resources per capita in 2020 (from Drinking water)
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Temperature dependence of the surface tension of pure water (from Properties of water)
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Density of ice and water as a function of temperature (from Properties of water)
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Building a map of groundwater contours (from Hydrology)
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Water treatment plant (from Drinking water)
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Estimates of changes in water storage around the Tigris and Euphrates Rivers, measured by NASA's GRACE satellites. The satellites measure tiny changes in gravitational acceleration, which can then be processed to reveal movement of water due to changes in its total mass. (from Hydrology)
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Vapor pressure diagrams of water (from Properties of water)
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Model of hydrogen bonds (1) between molecules of water (from Properties of water)
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The "F-diagram" (feces, fingers, flies, fields, fluids, food), showing pathways of fecal–oral disease transmission. The vertical blue lines show barriers: toilets, safe water, hygiene and handwashing. (from Drinking water)
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WOA surface density (from Properties of water)
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Water molecule - structure and dipole moment (from Properties of water)
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Drinking water vending machines in Thailand. One litre of potable water is sold (into the customer's own bottle) for 1 baht. (from Drinking water)
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World map for SDG 6 Indicator 6.1.1 in 2015: "Proportion of population using safely managed drinking water services" (from Drinking water)
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Drinking water that is supplied through a tap (tap water) (from Drinking water)
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This paper clip is under the water level, which has risen gently and smoothly. Surface tension prevents the clip from submerging and the water from overflowing the glass edges. (from Properties of water)
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The solid/liquid/vapor triple point of liquid water, ice Ih and water vapor in the lower left portion of a water phase diagram. (from Properties of water)
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Heat of vaporization of water from melting to critical temperature (from Properties of water)
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The Roman aqueduct at Caesarea Maritima, bringing water from the wetter Carmel mountains to the settlement (from Hydrology)
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Temperature distribution in a lake in summer and winter (from Properties of water)
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Poverty often leads to unhygienic living conditions, as in this community in the Indian Himalayas. Such conditions promote contraction of diarrheal diseases, as a result of contaminated drinking water, poor sanitation and hygiene. (from Drinking water)
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Red line shows saturation (from Properties of water)
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Example for physical and chemical parameters measured in drinking water samples in Kenya and Ethiopia as part of a systematic review of published literature (from Drinking water)
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Diagram of water well types (from Drinking water)
Wikiprojects
- WikiProject Rivers is a WikiProject which aims primarily to describe the Earth's rivers in a consistent and complete fashion. The parent of this WikiProject is the WikiProject Geography.
- WikiProject Water provides information on water purification.
- WikiProject Sanitation provides information on all issues surrounding sanitation, including wastewater management.
- WikiProject Lakes describes the Earth's lakes. The project aims to consolidate and unify pages relating to lakes around the world.
- WikiProject Dams is a WikiProject formed to organize and improve articles related to dams.
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