Glossaire de A à Z

"Threshold" value of the flow that triggers the first restrictions for some activities. These measures are taken at the initiative of the prefectural authority in connection with a crisis cell and in accordance with a crisis plan. Below this threshold, one of the functions (or activities) is compromised. To partially restore this function, it is necessary to limit temporarily another: withdrawal or discharge (first restriction measures)…

In the meaning of the law of July 15, 1975, any residue resulting from a process of production, transformation or use, any substance, material, product or more generally any movable asset abandoned, or that its holder intends to abandon.

Water that has been used by man. We usually distinguish wastewater from domestic, industrial or agricultural origin. These waters are discharged into the natural environment directly or through collecting systems with or without treatment. We also talk of sewage or effluent.

Extraction of fresh water from a groundwater source or surface, permanently or temporarily, and conveyed to the place of use. Water abstractions include all activities related levies generated by agriculture, industry (including energy), the supply of drinking water, or other (mineral spring authorized, production artificial snow).

Potential source of water supply to meet water needs related to some human activities. This resource can be artificial – e.g. a channel - or natural – e.g. a river or an ocean.

State Public institution of an administrative nature supervised by the Minister in charge of the environment. In a river basin or group of basins, the water agency is implementing the river basin management plan (SDAGE) and the sub-basin management plans (SAGEs), by enabling efficient and sound management of water resources and aquatic environments, drinking water supply…

A Local public institution located overseas, similar to the water agencies in continental France, which is responsible for facilitating the various activities of common interest in the management of water and aquatic environments to help achieving the objectives of the river basin management plans (SDAGEs). There is currently a water board in the Reunion, Martinique, Guadeloupe and Guyana. Since Mayotte became a Department, there are thoughts of creating a water board.

Expression of the calcium and magnesium content of water. It is measured in French degree (°f ou °TH).

Information system designed to meet the needs of stakeholders (including the general public) regarding public environmental information in the field of water. It collects, store and disseminates data and indicators on water, aquatic environments and on their uses. Its entry point is the www.eaufrance.fr portal. His technical management is entrusted to the national office for water and aquatic environments (Onema) under the authority of the Ecology ministry. The national framework for water data (NFWD) stipulates the role and responsibilities of each data producer as well as the components making up WIS-FR. It is based on the common language set up by Sandre, now the French national service for water data and common repositories management.

Water volume lost during its conveyance between the abstraction point and a point of use (due to leak or evaporation) or between the place of use and a place of reuse.

Natural (spring) or artificial access (drilling, drain, well, etc) to groundwater. Each water point has a national code (BSS code) and is located by geographic coordinates through a projection system. It is also defined by the following additional pieces of information: a name or label, an altitude, an address (locality), a location map.

Controlled evacuation of part of the water of a dam reservoir (low-flow period, security, energy production, etc.).

Fragmentation of a watercourse into several fragments, due to natural or artificial obstacles (i.e. sills, dams, weirs, etc), which may lead to a disruption into the ecological continuity, preventing the free movement of species or the smooth sediments flow.

Technology that enables applications to interact remotely via the Internet regardless of the platforms and languages on which they are based (see interoperability). The National Service for Water Data and Reference-dataset Management (Sandre) specifies web services by technical scenarios and disseminates its reference datasets by web services.

Marsh or area that can be flooded at high-flow or by water silting in the rainy season.

Natural environment marked by the temporary or permanent presence of water, hosting a specific flora and fauna. Examples include a marsh, bog, pond, pond, pond, estuary, etc.

An area where water, whether fresh, salty or brackish, is the main factor controlling the natural environment and the associated animal and plant life. Wetlands are fed by stream flow and/or rising water tables and are shaped by the alternation of high and low water levels. Examples include streams, peat bogs, ponds, ponds, ponds, banks, floodplains, salt meadows, mudflats, coastal marshes, estuaries. These areas are transition spaces between land and water (they are ecotones). The vegetation present has a marked hygrophilic character (which absorbs water). Like all these types of particular spaces, it has a strong biological potential (specific fauna and flora) and have a role in regulating flow and improving water quality.

There are several regulatory definitions of the term "Wetland" depending on the text: 

• According to article L211-1 of the Environmental Code, "wetlands are defined as "land, whether or not exploited, usually flooded or gorged with fresh, salty or brackish water on a permanent or temporary basis; vegetation, where it exists, is dominated by hygrophilic plants for at least part of the year".
• According to article R.211-108 of the Environmental Code, which specifies article L211-1: the criteria to be used to define a wetland are related to the morphology of the soil related to the prolonged presence of water of natural origin and the possible presence of hygrophilic plants, in the absence of hygrophilic vegetation, the morphology of the soil is sufficient to define a wetland, the delimitation of wetlands is carried out using flood or groundwater levels, or the frequencies and amplitudes of the tides.
• According to Article 1.1 of the RAMSAR Convention, a wetland is "an area of marshes, fens, peatlands or natural or artificial, permanent or temporary waters, where the water is stagnant or flowing, fresh, brackish or salt, including areas of…