The great water cycle
Appeared 3 to 4 billion years ago, it is always the same water which circulates and is constantly transformed between land, sea and sky, in the atmosphere, on the surface and in the subsoil of our Earth. . This course of water is called "the great water cycle".
Water is constantly circulating and changing. This is the great water cycle. Under the effect of the sun, the water in the seas and oceans evaporates. Like that contained in plants. This vapor condenses into fine droplets which gradually form clouds. With the cold, the droplets come together and form larger drops that eventually fall. Once on the ground, the water feeds the torrents, the rivers, the rivers and finally, the seas and the oceans. Another part seeps into the ground. It forms an underground aquifer. This can give rise to a water source. In turn, the water from this source flows and swells the river, the seas, the oceans. The circle is complete !
It is this same water that flows through your taps, distributed by Eau de Paris. Half come from the Seine and the Marne. The other half comes from groundwater collected in Ile-de-France, Burgundy and Normandy.
Made drinkable and distributed by Eau de Paris, then consumed, the water is then treated before being discharged into nature. It joins its great natural cycle.
The small water cycle
Capturing, treating, transporting, distributing: drinking water follows a path from source to tap before being drunk by Parisians. After use, the water is returned to the natural environment. This route is called "little water cycle".
Where does Paris water come from?
In Paris, the drinking water supply is guaranteed 24 hours a day, 24 days a week. Half of it comes from underground water captured by Eau de Paris within a radius of 7 kilometers around the capital: to the south in Provins, Sens, Fontainebleau; and to the west, near Verneuil-sur-Avre and Montreuil. The water is then transported via aqueducts without energy consumption, to be treated in the Eau de Paris factories. The other half of production comes from water from the Seine (treated at the Orly plant) and the Marne (treated at the Joinville plant). Once treated and made drinkable, the water is stored in 7 large reservoirs located at the gates of the capital before being distributed to Parisians via 150 kilometers of pipes. After use, the water is treated in treatment plants to be finally discharged into nature where it resumes its great natural cycle.
The origin of water in Paris
Paris water has two origins :
- half comes from groundwater collected in various places in Île-de-France, Burgundy and Normandy.
- the other half comes from river water: the Seine and the Marne.
Text transcript
POWER DIAGRAM
- Underground waters : from 0 to 50 m0/d
- Underground waters : from 50 to 000 m100/d
- Surface water: greater than 300 m000/d
Groundwater catchment area
Groundwater treatment plant
Surface water treatment plant
Reservoirs
Watchpoint
Paris Water website
Treated differently depending on their origin, this water is sent to Paris.
Groundwater
They come from rainwater that infiltrates the earth until it encounters an impermeable layer. They then form an underground aquifer. The different layers of sand, gravel or rock that they cross serve as filters. Then this water simply undergoes treatment with activated carbon and ultra-filtration to eliminate all traces of pollutants.
river waters
They are subject to a potabilisation process different from groundwater. The principle ? To imitate nature, by implementing a succession of filtration stages: they are first clarified by screening and filtration, then refined by ozonation, activated carbon and ultraviolet.
Depending on the neighborhood, Parisians benefit from a mixture of groundwater and water from purified rivers. Throughout Paris, the water distributed is subject to rigorous and permanent monitoring. Its traceability is total.
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Eau de Paris
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Our facilities
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My tap water
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