Risk

All the organisational processes, techniques and means used to prepare for a crisis, to cope with it and to mitigate its consequences. Crisis management includes alert, coordinated relief response and retrospective analysis of the sequence and effects of the first two phases.

State of the soil or of an environment resulting from a lack of rain. It generally occurs when the amount of rain is significantly lower than seasonal norms, and this over a fairly long period.

Area exposed or that could be exposed to hazards or potentially dangerous events (flood, pollution, natural disaster, industrial accident) and where human, economic or environmental issues are involved.

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).

Threat of a dangerous event caused by a natural phenomenon, called hazard, having damaging, unforeseen or badly prevented effects on developments, structures and people, the stakes being more or less serious, even catastrophic, according to their vulnerability. A natural risk is the confrontation between a hazard of natural origin and human, economic or environmental stakes.

Technological risk related to an industrial facility. Industrial risks are either chronic (resulting from the different kinds of pollution likely to have an impact on the health of populations and on the environment, such as emissions of toxic metals, volatile organic compounds or carcinogenic substances), or accidental (attributable to the presence of dangerous products or processes, likely to cause an accident with serious immediate consequences for workers, residents, property and the environment).

Travel of rising water levels from upstream to downstream of a watercourse.

Anticipation of phenomena that may cause or aggravate health, economic or environmental problems. Risk prevention aims to eliminate or reduce the probability of occurrence of hazardous phenomena at the origin of the risk.

Plain formed by the deposition of sediments from upstream erosion.