A Eau is known as potable' when it satisfies a certain number of characteristics making it clean with the human consumption.

The standards of reference in this field differ from the times and country to country (and according to the authority in load of this definition in certain countries). The concept of “ potability ” varies throughout the world, fruit of a historical and cultural context local.

For example, the parameters being able to be regulated are:

Example of general framework; the French system

Spring waters, mineral water

The water known as “of source” are water naturally suitable for human consumption. The only treatments which it is allowed to apply to them are ventilation, the decantation and filtration. Naturally gas water, which contains Carbonic gas dissolved, can also be gasified before being bottled.

The mineral water , they, are spring waters having particular properties: they have contents of Minéraux and trace elements which can give them therapeutic virtues. Like spring waters, they cannot be treated. A water can be qualified in France of mineral only if she were recognized like beneficial for health by the national Académie of medicine. In this direction, it is a Alicament.

Raw waters

Water quality rough (water resource before any treatment of potabilisation) will depend:

  • the authorization to take this Water to make it drinkable;

  • the die of suitable potabilisation.

Pursuant to the Community legislation, the surface waters intended for the food production must answer precise requirements for quality.

The current system of classification is articulated around two elements:

  • the parameters of quality to which the raw waters must answer in any event;

  • the process-type of treatment used for the potabilisation. The raw waters are classified in three categories, according to the intensity of the process:
  • # A1: Good quality, simple physical treatment and disinfection
  • # A2: Average quality, physical, chemical normal treatment and disinfection
  • # A3: Poor quality, physical, chemical treatment pushed, refining and disinfection.

distributed Water

A news European directive was adopted fine 1998 to replace the directive of July 15th, 1980 relating to water quality intended for human consumption. Its contents were transposed in French right by the decree 2001-1220 (decree n° 2001-1220 of December 20th, 2001 relating to the water intended for human consumption, other than natural mineral water. This text from now on is integrated in the Public health code (article L 1321).

Are subjected to the constraints of the water intended for human consumption (“the Tap water”):

  • all the water intended for drink, cooking, the preparation of food or other domestic uses;

  • all the water used in the food companies for manufacture, the transformation, the conservation or the marketing of products or substances, intended for human consumption, including the ice-cream of hydrous origin.

All this water must meet three conditions:

  • they should not contain a number or a concentration of micro-organisms, parasites or of all other substances constituting a potential danger for the health of the people;

  • they must be in conformity with the limits of quality (obligatory values). Thus, since December 25th 2003, the limiting value of 50 µg/L of lead in water of distribution passed to 25 µg/L. It will be lowered to 10 µg/L with Christmas 2013.
  • they must satisfy references of quality (indicative values of a good quality but whose nonspecific respect does not generate a health risk).

Sanitary control of water

The quality of the Drinking water is subjected to two types of controls, whether its distributer is public or private:

  • a official control , specific, which falls within the competence of the public authorities (DDASS). It is fundamental lawful control;

  • a permanent self-monitoring by the owners of their services of distribution (municipal controls or deputy companies).

The decree of authorization delivered by the prefect determines the points where sampling for purposes of analysis must be practiced:

  • on the level of the resource (in the river or the underground layer);

  • on the level of the production, i.e. after treatment and before the sending of the Water in the distribution network;
  • on the level of the distribution network;
  • at the point of consumption. It is a important Innovation of the decree 2001-1220: for the water provided by a distribution network, the limits and references of quality must be respected at the point where water leaves the taps .

In the event of Pollution

What does it occur when water does not respect more the requirements of quality? The distributer, public or deprived, have an obligation of alarm as soon as it notes the non-observance of the requirements for quality. It must:

  • to immediately inform the Mayor and the Prefect;

  • to carry out an investigation in order to determine the cause of nonconformity;
  • to communicate immediately to the Mayor and the Prefect observations and conclusions of the investigation.

In the event of going beyond of the limits of quality, it must also take corrective measures to restore water quality, “that non-observance is or not ascribable with the private installation of distribution”.

Processes of treatment

Physical and physicochemical processes

Chemical processes

The Oxidation, by the Chlorine or the Ozone, acts on metals (iron, manganese), on the organic matters and destroyed or inactive the alive germs, the viruses and the bacteria. The processes of substitution of ions per exchange of ions on specific resins are used for the denitratation and the softening water.

Biological processes

Suitable bacterial cultures put in contact with water to treat eliminate certain undesirable elements.

Membrane processes

  • ultrafiltration

  • the nanofiltration
  • osmosis reverses

Muds

The various treatments produce muds. In the majority of the cases, they are dehydrated, then put in discharge, épandues or sent towards the purification plant.

Management of water

On: 36700 communes existing in France: 23000 are gathered in: 2000 inter-commune co-operation bodies to set up a common single water service. The greatest French public agency in the field of water is the Syndicat interdépartemental water of the north of France, which gathers 650 primarily rural communes of the Northern , of the Pas-de-Calais and the Aisne.

More: 13000 communes manage water in an isolated way.

Some communes are deprived of public network of water supply, but they comprise only one very low number of inhabitants and, today, 99% of the French population are connected to a drinking water network.

Two principal management styles are met:

  • direct management or “governed”. The commune (or grouping of communes) directly ensures the service of water and/or the cleansing, with its own personnel. The territorial collectivity finances the works necessary and preserves the control of the services and their management.

  • the deputy management . Certain communes can choose to delegate their service of water and/or cleansing at a specialized company. It is not a question of a “privatization”: the commune exerts a control on the execution of the service, into fixed partly the price for the consumers and preserves the property of the equipment. In this case the specialized private company releases from the benefit on the sale of water, contrary to the inter-commune expertise, co-operation bodies n the other hand brought for this management. The intermediate duration of these contracts is de12 years in France (30 years in the United Kingdom).

Contrary to the generally accepted ideas, the public sphere accounts for 60% of the turnover of the sector of water and the drainage work; the private operators only 40%. The number of the latter does not cease growing and to the companies centenaries which are Véolia Eau, Lyonnaise Water, is added local actors like Alteau, Sogedo, Saur, Ruas.

Price of water

According to a study of NAKED Consulting (in January 2006), the total average costs per m of water recorded in Europe are established with 3,02 € per m . In addition to France, the study related to the following countries: Germany, Belgium, Denmark, Spain, Finland, Italy, Netherlands, the United Kingdom and Sweden. According to a study of NAKED Consulting (in July 2006) it would be about 1,5 US$ per m excluding VAT.

France is, with 2,77 € per m (that is to say 0,0027 € per liter), in the low fork among the ten, after Sweden, Spain and Italy. The average costs vary between 0,79 € the m in Italy and 5,12 € the m in Denmark. In fact the countries of the north of Europe are most expensive except for Sweden.

The price of water corresponds to the whole of the operations which concern: production of drinking water, distribution and, in majority cases, the depollution of waste water.

In: 2000, approximately 42% of the price of water were related to the drinkable water supply;

approximately 31% relate to the collection and the treatment of waste water;

approximately 27% correspond to royalties and taxes, of which VAT.

The royalties are intended at public agencies (as the agencies of the water) from which the mission is to protect the water natural resources and to finance equipment for the drinking water supply or the protection of the natural environment.

Human needs

The Homme has an average need on a world level for 20 to 50 liters for water per day (food, Hygiène, etc). A child in a Pays developed consumes 30 to 50 times more water than in a Pays in the process of development.

More than one billion people remain excluded from a water provision (primarily in Asia and Africa) whereas 2,6 billion does not have service of Assainissement.

In 2006: 22000 people die each day because of an unhealthy water consumption

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