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Amphibian

Updated on 04/07/2018
Définition
Sens commun

Vertebrate animal that has the characteristic of starting its life in the water. At birth, an amphibian breathes through its gills, like a fish. As an adult he now has lungs through which he can breathe freely, but he continues to absorb most of the oxygen he needs through the skin.

Source
according to Aquitaine Wildlife Observatory (AWO)

Needle dam/weir

Updated on 06/09/2018
Définition
Sens commun
Dam consisting of a succession of solid frames (foldable metal frames) connected by a bridge and each supporting a movable part - the needle - which can be raised or lowered.
Source
according to Voies navigables de France (French Waterways)

Earth dam

Updated on 06/09/2018
Définition
Sens commun
An embankment, formed of compact earth, built across the bed of a river to create a water reservoir. This is the simplest and oldest type of dam. Its slopes must be soft enough to ensure stability and the earth must be sufficiently impermeable (e.g. clay).
Source
according to the French Committee of Dams and Reservoirs

Hydropower dam

Updated on 06/09/2018
Définition
Sens commun
A structure built on a watercourse for creating a water reservoir to ensure a constant production of electricity. The impounded water of the reservoir is conveyed by pipes to the power plant.
Source
according to the French Committee of Dams and Reservoirs

Gravity dam

Updated on 06/09/2018
Définition
Sens technique
A rather old dam, made of a block of solid material (concrete or masonry) heavy enough to withstand the water pressure.
Source
according to the French Committee of Dams and Reservoirs

Impoundment dam

Updated on 06/09/2018
Définition
Sens technique
Structure built for the storage of water for replenishing low water levels or supplying channels.
Source
according to Voies navigables de France (French Waterways)

Underground dam

Updated on 06/09/2018
Définition
Sens technique
A groundwater impoundment structure built across underground water channels. The underground dams are built in the sub-soil. They store water in geological formations, retain groundwater and require pumping facilities to make water usable.
Source
according to the Japanese Ministry of the Environment

Arch dam

Updated on 06/09/2018
Définition
Sens technique
Dam with a complex design, which is thin and resistant to the hydraulic pressure by bracing the rocky sides of a valley. These dams are particularly suitable for narrow valleys.
Source
according to the French Committee of Dams and Reservoirs

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

Meander cutoff

Updated on 06/09/2018
Définition
Sens commun
A cutoff that occurs when two knees of the same meander meet. The cutoff then causes the abandonment of the meander to form a new channel.
Source
according to Wikipedia

Excavation

Updated on 06/09/2018
Définition
Sens commun
Action to remove soil or rubble to level or lower the soil.
Source
according to the National Centre for Textual and Lexical Resour

Delta

Updated on 06/09/2018
Définition
Sens commun
A type of river mouth characterised by heavy siltation at an elevation very close to that of the water surface and forming a natural marshy plain.
Source
according to IFREMER

River diversion

Updated on 06/09/2018
Définition
Sens commun
Temporary or definitive man-made change in the layout of a watercourse by totally or partially diverting the water flow.
Source
according to AFB and Réseau ferré de France (French railway network)

Pruning

Updated on 04/12/2018
Définition
Sens commun
The process of cutting off, in a selective manner, branches from a tree to orient or limit its growth.
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

Soil erosion

Updated on 06/09/2018
Définition
Sens commun
Thinning of the topsoil of a field as a result of the natural erosive forces of water and wind, or as a result of agricultural activities such as tillage. Soil erosion lowers the productivity of the land and contributes to the pollution of adjacent rivers, wetlands and lakes.
Source
according to Ontario Ministry of Agriculture

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

River morphology

Updated on 06/09/2018
Définition
Sens commun
Study of the shape of rivers.
Source
according to AFB

Alluvial plain

Updated on 06/09/2018
Définition
Sens commun
Plain formed by the deposition of sediments from upstream erosion.
Source
according to UNESCO

Bridge

Updated on 04/12/2018
Définition
Sens commun
Structure linking two points separated by a stream, a valley or any other obstacle.
Source
according to the Robert dictionary and IOWater

Backfilling

Updated on 06/09/2018
Définition
Sens commun
Work or the lifting of fill materials, generally intended to ensure the continuity of level for a structure.
Source
according to the National Centre for Textual and Lexical Resources

Hydrodynamics

Updated on 06/09/2018
Définition
Sens commun
Branch of fluid mechanics which concerns the motion of fluids, whether liquid or gaseous. Hydrodynamics focuses on the properties of fluids, including velocity, viscosity, density, pressure, and temperature, as a function of space and time.
Source
according to the Larousse dictionary

Charges/fees for obstacle on rivers

Updated on 06/09/2018
Définition
Sens commun
Amount due by any owner of a structure that constitutes a continuous obstacle between the two banks of a watercourse (except for structures forming part of hydroelectric installations subject to the fee for water resource abstraction, or where the height difference is less than 5 m, or located on rivers whose average interannual flow is less than 0.3 m3/s at the right of the obstacle).
Source
according to the Ministry of the Environment, the Court of Auditors and Water Agencies

Sedimentory basin

Updated on 25/02/2019
Définition
Sens commun

Portion of the Earth's crust on which has been deposited, or still is depositing, many layers of sediment, produced by the alteration of preexisting rocks. Over time, significant accumulation of sediments causes the depression of the deposition zone, and allows the addition of new layers, creating a sedimentary basin.

Source
according to CNRS

Regional ecological coherence scheme

Updated on 25/02/2019
Définition
Sens technique

Framework Document elaborated in each metropolitan area, by the Regional Council and the regional prefect, in association with local stakeholders, locally developed the green and blue infrastructure. The Regional Ecological Coherence Scheme (SRCE) is to identify biodiversity reservoirs and ecological corridors that link them. It includes an action plan to ensure the preservation and restore ecological continuity identified while taking into account land use planning issues and human activities. The SRCE must also be compatible with the planning documents, such as territorial coherence…

Source
according to IOWater