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Groundwater depletion

Updated on 06/09/2018
Définition
Sens technique
Permanent or temporary drop in the piezometric level of groundwater, due to a natural or artificial change in its recharge or abstraction.
Source
according to the Adour-Garonne Water Agency and BRGM

Groundwater recharge

Updated on 13/07/2018
Définition
Sens technique

According to the hydro-geological meaning, a water volume supplying an aquifer over a given time. Rainfalls are mainly recharging groundwater. Unconfined groundwaters are recharged rather fast at each rainfall event. The rise in water levels and rainfall events are observed on a piezometric curve.

Source
According to BRGM

Elevation of the piezometric record

Updated on 13/07/2018
Définition
Sens technique

Elevation defined either in NGF level (French levelling network) or in relative depth. The NGF level, established under the control of the National Geographic Institute (IGN), is the reference. NGF can indeed express altitudes in one and unique reference system, i.e. as compared to the same and unique fundamental point (or "origin-zero" or point zero). The "0" level is the average sea level in Marseilles. This point is used to determine the altitude of any other point. The elevation of the piezometric record can also be expressed in relative depth with respect to the benchmark of the

Source
According to BRGM

Piezometric record

Updated on 13/07/2018
Définition
Sens technique

The piezometric record is the collecting of the evolutions in time of the monitored groundwater level or piezometric level (see piezometric level). It consists of measurements that link the water level to a given date. Depending on the variability of groundwater level, the measurements are more or less close in time. The measurements obtained are positive or negative with respect to the measurement benchmark: they are positive when the groundwater level is below the benchmark measurement (the most common cases) and negative in the opposite case (artesian wells). Artesian: a well is artesian when the water is gushing. A record is represented by a curve which is time-slotted to be stored in a succession of points, each point representing a groundwater level at any given time. Points are linked to each other by means of a code that indicates whether a point is related to the preceding point in time. If the point is not related, it is then the initial point of a new part of the record…

Source
According to BRGM

Piezometric level

Updated on 13/07/2018
Définition
Sens technique
Level reached by water at one point and at a given time in a pipe reaching the groundwater sheet. The piezometric level can be transferred to a piezometric map. Some non-operated wells are used to measure this level, they are piezometers or observation wells. This level corresponds to the groundwater pressure; it is usually indicated in NGF metres (French Surveying and Levelling). When this level is above ground level, the groundwater is called artesian: water is gushing out. The piezometric maps established with all measured data give a graphical representation of the groundwater surface and can track its evolution over time and identify its direction of flow.
Source
According to BRGM

Groundwater ridge

Updated on 13/07/2018
Définition
Sens technique
Groundwater divide. Line at zero flow (no flow) between two adjacent groundwater basins. On each side of this ridge, the values of the measured piezometry (see this term) are lower than those measured (or estimated) on the ridge.
Source
According to the Ministry of Ecology

Quantity objective

Updated on 13/07/2018
Définition
Sens technique

Value (flow rate of streams, groundwater level, reserve storage, etc) necessary for the quantitative management of the resource. The quantity goals are set to achieve a satisfactory balance between the demands of human activities and the requirements of aquatic environments on the one hand; and the surface and groundwater resources that can be mobilized, on the other. At nodal points, these values are the

Source
According to the Ministry for the Environment and AFB

Drawdown

Updated on 13/07/2018
Définition
Sens technique
Lowering of the groundwater level at a given point by the extraction of water from the water table, the lowering of a water line of a stream in relation with groundwater or under the influence of earthworks, etc.
Source
According to the Ministry for the Environment and AFB

Piezometry

Updated on 13/07/2018
Définition
Sens commun
Depth of the water level in the soil.
Source
According to Poitou-Charentes Regional Council

Water abstraction

Updated on 25/02/2019
Définition
Sens commun

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).

Source
according to AFB, IOWater, SOeS and OCDE

Abstraction supply zones

Updated on 25/02/2019
Définition
Sens technique

Area on which the water that soaks into the ground supplies the abstraction for drinking water.

Source
According to the Ministry for the Environment and the Ministry for the Agriculture

Flood warning

Updated on 08/04/2020
Définition
Sens commun

Warning issued in advance by the departmental flood forecasting services. In the event of heavy rainfall or hydrological alert, a flood warning is sent to the Prefect, who then alerts the mayors of the catchment areas concerned.

Source
according to OFB
Sens technique

Warning issued in advance by a special state service (flood forecasting service). In the event of a rainfall or hydrological alert (triggering when thresholds are exceeded), the flood forecasting service offers the Prefect the alert of the mayors of the watersheds concerned. As a severe overflow flood, the flood warning service broadcasts, for prefects and mayors, hydrological situation bulletins and information on the evolution of water levels . In 1994, 54 flood warning services monitored 16,000 km of waterways in France using automated measurement networks.

Source
According to Ministry of the Environment and OFB

Hydrological balance

Updated on 06/09/2018
Définition
Sens technique
Accounting of the changes in water resources (stream flows, groundwater level, effective rainfall) of an area (for example a catchment area) based on meteorological, piezometric or hydrological information.
Source
according to AFB

Hydropower plant

Updated on 04/12/2018
Définition
Sens commun
Facility that produces electricity by the force of moving water.
Source
according to AFB
Sens technique
Hydroelectric facility transforming hydraulic energy into electricity, whose power usually varies from a few kW to 4,500 kW.
Source
according to IFREMER

Dam release

Updated on 06/09/2018
Définition
Sens technique
Operation to lower water level and increase outflow rates to discharge some of the sediment retained by a dam. A dam release consists in opening the gates, thus limiting the silting of the dam reservoir and the risk of flooding. This operation, although common in the management of harnessed rivers, can have adverse effects on the downstream environment (decrease of oxygen levels in water, obstruction of fish gills by suspended solids, etc.).
Source
according to ISTREA

Stagnant water

Updated on 06/09/2018
Définition
Sens commun
Still water in parts of a river, lake or other aquatic environment.
Source
according to UNESCO

Green water

Updated on 06/09/2018
Définition
Sens commun
Water contained in the soil and available for plants.
Source
according to AFB

Groundwater/river exchange

Updated on 06/09/2018
Définition
Sens commun
Exchange of water in one direction or the other between an aquifer and a river. Depending on the level of the water line, and on the season, groundwater feeds the river or is fed by it, particularly during floods. In the case of karst, these relationships are important and localised.
Source
according to AFB

Silting

Updated on 06/09/2018
Définition
Sens technique
Deposit of fine sediments made of rock particles and silt or clay. Siltation is a form of sedimentation with mud. Streams carry a few million cubic meters of sediment each year. Their deposit causes the silting of these rivers, canals, and bodies of water. This quite natural phenomenon is accentuated by a flat topography, low flows, erosion processes, as well as industrial and urban discharges.
Source
according to AFB and INRA

Snow melt

Updated on 06/09/2018
Définition
Sens commun
Transformation of snow into liquid water.
Source
according to UNESCO

Hydraulics

Updated on 06/09/2018
Définition
Sens commun
A branch of fluid mechanics that deals with the flow of water (or other liquids) through pipes, open channels and other structures.
Source
according to UNESCO

River hydraulics

Updated on 06/09/2018
Définition
Sens technique
Branch of Hydraulics which mainly deals with the free surface flow of water in natural or artificial streams (e.g. canals). River hydraulics is necessary for the design, development and construction of hydraulic structures, such as dikes, sills and weirs.
Source
according to Wikipedia

Marine hydraulics

Updated on 06/09/2018
Définition
Sens technique
A branch of hydraulics related to the marine and coastal environments, which deals with swells, currents, dispersion and water quality, sedimentology, seaworthiness and the keeping of ships at station, or the interaction between waves and structures.
Source
according to Egis

Groundwater Hydraulics

Updated on 06/09/2018
Définition
Sens technique
A branch of hydraulics that mathematically studies the natural gravity flow (of an aquifer) or the induced flow (by drainage or pumping, for example) of free groundwater in permeable media, under the effect of a hydraulic or pressure gradient.
Source
according to Wikipedia