‘Moor Lane’ Flood Risks

Woking Borough Council publishes a series of detailed maps that supports the Strategic Flood Risk Assessment (SFRA) for the River Wey catchment. They can be found here: Flooding Maps.

The SFRA examines the causes, transmission mechanisms and effects of flooding as per the diagram below:

I have downloaded and attached the specific maps for our area covering:

• Environment Agency Flood Map – AppendixB1_DRG04
• Detailed Map of River Flooding – AppendixC_DRG04
• Flood Depth Mapping – AppendixD1_DRG04
• Sources of Flooding – Overloaded Sewers – AppendixE1_DRG04
• Sources of Flooding – Surface Water Sewers – AppendixE2_DRG04
• Sources of Flooding – Foul Water Sewers – AppendixE3_DRG04
• Sources of Flooding – Combined Sewers – AppendixE4_DRG04

So what does this tell us?  Well…

1. the eastern part of the proposed development site is part of the functional flood plain with the highest risk of flooding from existing water courses;
2. The western part of the site falls within an area with the highest incidents of flooding from overloading from existing sewers (i.e. the sewer infrastucture needs upgrading);
3. The eastern part of the site falls within Flood Zone 2 & 3 and have a medium or high risk of flooding.

All sites in Flood Zones 2 and 3 will require a site specific Flood Risk Assessment The application of the Sequential Test at these sites must demonstrate that there are no reasonably alternative sites within areas at lower risk of flooding. Following application of the Sequential Test and the demonstration that there are no reasonably available alternative sites in areas at lower risk of flooding, some sites in these zones may require the application of the Exception Test, depending on the vulnerability of the proposed development to flooding to demonstrate that the sites are safe and do not exacerbate the flooding situation – Source: Woking Borough Council SFRA.