Flood risk

How to use the strategic flood risk assessment

In accordance with the National Planning Policy Framework (NPPF) and associated Planning Practice Guidance, the SFRA has been structured in a two level approach. The Level 1 SFRA provides an overview of the flood risk issues for the purposes of the application of applying the NPPF Sequential Test. The aim of the Level 2 study is to provide supplementary information to the Level 1 SFRA, to inform on flood risks associated with allocation sites that may require the Exception Test as identified in the LB Wandsworth Sequential Test as part of the preparation of the Local Plan. This report aims to provide sufficient information to inform the application of the NPPF Exception Test. Both the Level 1 and Level 2 reports have now been finalised in liaison with key partner organisations including the Environment Agency, Thames Water Utilities Ltd, Network Rail and Transport for London.

The Level 2 SFRA details the methodology and results of an extensive tidal flood modelling and mapping exercise, which has looked at residual flood risk from breach or overtopping of existing defences. In addition, it includes the Environment Agency's  River Wandle modelling and associated mapping with respect to the fluvial flood risk areas in the Borough.

The Level 2 mapping compliments that produced in the Level 1 SFRA, to provide a complete suite of flood mapping from all sources, based on available data. The Level 1 and 2 reports should be used in conjunction with each other for both forward strategic planning and to inform ongoing development management decisions.

The SFRA informs the preparation of policy on flood risk within Local Plan documents, and provides the basis from which to apply the Sequential test and Exception test in site allocations and to inform planning applications and the development management process.