They are produced for areas where a potentially significant flood risk has been identified and show the extent of flooding caused by floods with varying probabilities of occurrence, from more frequent floods (once every 10 years) to extremely rare and extreme floods (once every 1,000 years). They are an invaluable basis for spatial planning, building decisions and the design of protective measures.
They provide a more detailed look at the potential adverse consequences of flooding. They combine information on the likelihood of flooding with data on the vulnerability of the area, i.e. what facilities, infrastructure, population or natural assets are located in the flooded area. Their use is wide ranging, from decision support for local and national governments, to insurance, to informing residents and planning evacuation in the event of a flood event.