The Flood Map for Planning (FMfP) includes climate change information to show how this will affect flood risk extents for rivers, the sea and surface water and small watercourses over the next century. It shows the potential extent of flooding assuming no defences are in place. It also indicates areas at risk from coastal erosion, areas that have flooded in the past and key information on the location of flood defence infrastructure.
The FMfP can be considered as the best available information on flood risk and will replace the Development Advice Map for planning purposes in June 2023. Although it currently has no official status for planning purposes it is a useful data source when considering flood risks.
More information on the formal implementation of the new TAN15 and FMfP is set out in the Written Statement from the Welsh Government https://gov.wales/written-statement-suspension-new-technical-advice-note-15-development-flood-risk-and-coastal
The Flood Zones within the FMfP shows the undefended risk of flooding from Rivers, the Sea and from Surface Water & Small Watercourses.
Flood Zone 3 displays the extent of flooding from:
• rivers with a 1% (1 in 100) chance or greater of happening in any given year, including an allowance for climate change.
• the sea with a 0.5% (1 in 200) chance or greater of happening in any given year, including an allowance for climate change.
• Surface water & small watercourses with a 1% (1 in 100) chance or greater of happening in any given year, including an allowance for climate change.
Flood Zone 2 displays the extent of flooding from:
• Rivers with less than 1% (1 in 100) but greater than or equal to 0.1% (1 in 1,000) chance of happening in any given year, including an allowance for climate change.
• the Sea with less than 0.5% (1 in 200) but greater than or equal to 0.1% (1 in 1,000) chance of flooding in any given year, including an allowance for climate change.
• Surface water & small watercourses with less than 1% (1 in 100) but greater than or equal to 0.1% (1 in 1,000) chance of happening in any given year, including an allowance for climate change.
The FMfP is displayed in two parts, a Basic View and a Detailed View. In the Basic View the risk of flooding from Rivers and the Sea is shown as a merged layer. In the Detailed View flood risk is separated into individual sources. In both Views Flood Zones for Surface Water & Small Watercourses are shown separately.