definitionFlood forecasting is an important component of flood warning. Flood forecasting involves prediction of water levels and flows at particular locations at a particular time, while flood warning is the task of making use of the flood forecasts to make decisions on whether flood warnings should be issued to the general public. A flood warning system is a way of detecting threatening events in advance. This enables the public to be warned so that actions can be taken to reduce the adverse effects of the event. As such, the primary objective of a flood warning system is to reduce exposure to flooding. Typically it is the role of the flood modeler or manager to pass on information to the appropriate authorities, which then has the responsibility to warn the general public or properties of the impending flood risk (René R., et.al., 2013, p. 3). Flood forecasting and early warning is carried out to reduce risks in flood prone areas. This tool is tailored for use when decision‐makers need to establish an effective overview of the flood situation, provide timely and accurate early warnings and flood forecasting services to a variety of users. Many countries have already integrated flood forecasting and early warning measures into their local and national emergency planning systems. This tool provides a concise overview of concepts and approaches in flood forecasting and early warning that helps flood managers and practitioners to develop and operate flood forecasting and early warning systems in flood prone areas.
(Associated Programm on Flood Management, accessed on Sept. 2016)
Co-benefits and impactsThe importance of having effective flood forecasting and early warning systems is widely accepted as one component to manage flood risk. Providing advance forecasting and warning of flood events can potentially allow the risk to life to be minimised, evacuation of vulnerable groups, residents to move assets (e.g. food, livestock, personal effects) to safer locations, timely operation of flood control structures (e.g. storm surge barriers, temporary flood defences, etc.) to prevent inundation of property and land, installation of flood resilience measures (e.g. sandbags, property flood barriers), pre-event maintenance operations to ensure free channel conveyance. If warnings can be disseminated to the public, it will also be possible to give communities advice on what to do in the event of a flood, as well as providing further information to limit losses. This may include areas to be evacuated, evacuation routes and the location of refuges for evacuees. It is likely that advice and guidance can be issued through the same channels used to notify communities of the flood risk as well as being made available prior to flood events. Flood warning technologies are relatively low-cost and have been successfully employed in a diverse range of countries from developed countries to developing ones.
(ClimateTechWiki, Flood warnings, accessed on Sept. 2016)
Case studies (Show all)Flood forecasting and early warning, Marbella
Flood forecasting and early warning, Marbella
Emergency Operation Centre, Marbella
Flood forecasting and Early warning, Les Boucholeurs
Sources (Show all)[X. Llort, R. Sanchez-Diezma, A. Rodriguez, D. Sancho, M. Berenguer, D. Sempere-Torres, 2014]
[A. Rodriguez, X. Llort, D. Sancho, R. Sanchez-Diezma, R. Bella, V. Gomez, 2014]
[Grasso V., Singh A., and Pathak J., 2012]
FRI indicators (Show all)Support of announcements (e.g. via email, SMS) to target groups by the EWS
Use of an Early Warning System (EWS)
Use of a real-time monitoring in the river network
Use of a real-time monitoring of hydraulic structures and urban drainage system
Responsible authorities Learning and adapting from previous events
Multidisciplinary knowledge exchange (engineer, architect/urban planner, sociologist, economist, politician - city government, etc.)
Knowledge exchange between scientific community and authorities
Illustrations (Show all)rm_images/Flood_EWS_01.png
Last modified: Sept. 16, 2016, 6:50 a.m.