Watercourse

Flow, or the lowest water level of the year, as measured by the water level or by the flow. During a period of low water, the river only takes a minor bed.

Chlorophyllous aquatic plant having no leaves, no roots, no vessels, no flowers, no seeds, whose main photosynthetic pigments are chlorophylls a and b. As the name suggests, they are usually green in color.

Algae phylum whose sometimes exclusive major pigment is chlorophyll β, associated with carotene and xanthophyll. Their only reproductive organs are sporocysts and gametocysts. Their plastids elaborate starch as in the Phanerogamous. It includes three classes: Chlorophyceae, Zygophyceae and Charophyceae.

Discharge of effluents or pollutants into watercourses.

Methodology, based on the study of stream flows, which allows assessing the water inflow that is specific to any section of the river.

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.

A harnessed river or canal open to traffic and waterways transport.

Movable device for stopping or leaving free passage to water. For example: gates are used by dams or locks, valves in hydropower plants.

Mode of transporting goods or people through the national and international waterways networks.

Salmonid farming (mainly trout and salmon). Fragile and very demanding, salmonids prefer fresh, pure and oxygen-rich waters. Salmon-trout farming requires a lot of technicality and a permanent control to ensure the good health and the optimal comfort of the fish. The production sites (basins) are mostly located on the river upstream of the catchment area or in the headwaters. Salmon farming is a branch of fish farming, which is practiced in both fresh and salt water.

Partial or total destruction of a dike. The causes of failure can be technical (defects in design, construction or materials, ageing of the structure), natural (following earthquakes, exceptional floods, a storm, a marine submersion, landslides, weakening by the burrows of animals) or human (not enough preliminary studies and project control, error of use, lack of monitoring and maintenance, malicious mischief).