A Strategic Flood Risk Assessment (SFRA) is a study carried out to assess the risk to an area from all sources of flooding, now and in the future, taking into account the impacts of climate change, as well as assessing the cumulative impact that land use changes and development in the area will have on the flood risk. It identifies opportunities to reduce the causes and impacts of flooding and gathers information on the land that is likely to be needed for flood risk management infrastructure. It also informs policies for change of use and reducing the causes and impacts of flooding.
Portsmouth City Council has commissioned AECOM on behalf of ten local planning authorities in South Hampshire (the ‘Partnership for South Hampshire’ (PfSH)) to prepare an updated SFRA, replacing the previous PUSH SFRA 2016.
The SFRA is split into two reports and a series of maps, published as appendices. These reports are accessible below. The main report provides an overview of the issues and sets out the approach to flooding across the South Hampshire sub-region. The Portsmouth SFRA report provides further information on the sources and extent of flooding in the City.
The full reports for all the PfSH local authorities are hosted on the PfSH website.
Documents
Main report
SFRA Level 1 Part 1 Main Report
SFRA Level 1 Part 1 Appendix A – Technical Note Fluvial River Floodplain Analysis
SFRA Level 1 Part 1 Appendix B1 – Technical Note: East Solent Model Re-Simulations
SFRA Level 1 Part 1 Appendix B2 – Technical Note: Southampton Water Model Re-Simulation
Portsmouth Report
Appendix A – Mapping
Figure 2 – Recorded Flood Outlines
Figure 3 – Risk of Flooding from Surface Water
Figure 4 – Areas Susceptible to Groundwater Flooding
Figure 5 – Susceptibility to Groundwater Flooding
Figure 6 – Risk of Flooding from Reservoirs
Figure 7 – Potential for Cumulative Impact of Development on Flood Risk
Figure 8 – Opportunities to Reduce Causes and Impacts of Flooding
Figure 9 – Flood Warning Areas
Figure 10 – Flood Risk Management Policies
Figure 11 – Tidal Flood Extent, Defended 3.3 AEP
Appendix B
Figure 1 – Coastal Erosion Risk
Figure 2 – Future Coastal Flood Zones
Figure 3 – Maximum Flood Depth 0.5% AEP 2022
Figure 4 – Maximum Flood Depth 0.5% AEP 2055
Figure 5 – Maximum Flood Depth 0.5% AEP 2122
Figure 6 – Maximum Flood Depth 0.5% AEP 2122 (Upper End)
Figure 7 – Maximum Flood Depth: Defended 1 in 1000 year (0.1% AEP) 2122 (Upper End)
Figure 8 – Maximum Flood Depth: Undefended 1 in 200 year (0.5% AEP) 2122 (Upper End)
Figure 9 – Maximum Flood Depth: Undefended 1 in 1000 year (0.1% AEP) 2122 (Upper End))
Figure 10 – Maximum Flood Hazard: Defended 1 in 200 year (0.5% AEP) 2022 (Higher Central)
Figure 11 – Maximum Flood Hazard: Defended 1 in 200 year (0.5% AEP) 2055 (Higher Central)
Figure 12 – Maximum Flood Hazard: Defended 1 in 200 year (0.5% AEP) 2122 (Higher Central)
Figure 13 – Maximum Flood Hazard: Defended 1 in 200 year (0.5% AEP) 2122 (Upper End)
Figure 14 – Maximum Flood Hazard: Defended 1 in 1000 year (0.1% AEP) 2122 (Upper End)
Figure 15 – Maximum Flood Hazard: Undefended 1 in 200 year (0.5% AEP) 2122 (Upper End)
Figure 16 – Maximum Flood Hazard: Undefended 1 in 1000 year (0.1% AEP) 2122 (Upper End)