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 FMfP introduces a new layer called the TAN15 Defended Zone. This shows areas that benefit from risk management authority owned flood defence infrastructure, that have a minimum, Present Day level of protection of:
• 1% (1 in 100) annual event probability (AEP) for rivers, or
• 0.5% (1 in 200) annual event probability (AEP) for the sea.
Flood defences built after 1 January 2016 must also include design freeboard and an allowance for climate change.
TAN15 Defended Zones are created for individual sources of flooding (i.e. Rivers or Sea). There are no TAN15 Defended Zones for Surface Water & Small Watercourses.