Definitions

Component: Discrete part of a system capable of operating independently but designed, constructed, and operated as an integral part of the system. Examples of individual components are wells, pumping stations, storage tanks, reservoirs, pipes, etc.

Drinking water system: Components constructed and installed to collect, transmit, treat, store, and distribute water to users. In broad terms, it also comprises the watershed and aquifers.

Emergency: Situation presented by the impact of a disaster.

Emergency and preparedness program: Comprises the emergency and mitigation plans.

Emergency plan: Measures to be applied before, during, and in response to the impact of a disaster.

Hazard: Phenomenon of nature or caused by human activity whose occurrence poses danger for per-sons, property, installations, and the environment.

Impact: Effects on the environment and on man-made works as a result of a disaster.

Mitigation plan: Measures and works to be implemented before the occurrence of a disaster, with the objective of reducing the impact on the components of the systems.

Natural disaster: Occurrence of a natural phenomenon in a limited space and time that disrupts nor-mal patterns of life, causing human, material, and economic loss.

Natural phenomenon. Manifestation of the forces of nature such as earthquakes, hurricanes, volcanic eruptions, etc.

Operative capacity: Capacity for which a component or system was designed.

Preparation: Measures that should be implemented before the occurrence of a disaster.

Prevention: Preparedness activities meant to diminish or prevent the impact of disaster.

Redundancy: Ability of system components to operate in parallel fashion; this allows continuity of service, despite the loss of one or more components.

Reliability: Ability of a component or system to resist hazards. Quantified as the complement of probability of failure.

Risk: The evaluation, based on conditional probability, that the consequences or effects of a specific hazard will exceed predetermined values.

Sewerage system: Components constructed and installed to collect, transmit, treat, and dispose of water and treatment products.

Vulnerability analysis: Process to determine critical components or weaknesses of systems to hazards.

Vulnerability: Susceptibility to the loss of an element or group of elements as the result of a disaster.

Water authority: Public, private or combined entity responsible for the provision of drinking water and sewerage service.