Appeal 3363543

The appeal is dismissed.

The main issue is the effect of the proposal on the management of flood risk.

The appeal dwelling is a semi-detached two storey house The proposal is for a flat roofed single storey rear extension, which would be approximately the same width as the appeal dwelling and project approximately 3 metres from its most rearward part. The appeal dwelling is located in a local area defined by the Environment Agency as being in [name] 2. The local area is further identified in the Council’s Strategic Flood Risk Assessment as being in an area at increased flood risk in future and having a medium 1 in 100 year risk (+17% climate change) from a surface water flood event.

Section 14 of The National Planning Policy Framework (2024) (the Framework) sets out that new development should be planned in ways that manage such risks. Paragraph 176 of the Framework sets out that minor development, including that of an extension should still meet the requirements for site specific flood risk assessment. Paragraph 181 and 182 of the Framework sets out that such assessments should demonstrate how risks have been appropriately managed or ameliorated, including through sustainable drainage systems and that safe access and escape routes are identified as part of an emergency plan.

The appellant in their statement states that they have addressed all the concerns raised by the council with regard to flood risk, as set out in their [name] Assessment1 (FRA) submitted as part of the original application. This includes 1 Flood Risk Assessment: [name] (2024) indicating that a garden pond would be included as part of the [name] (SUDS) on site.

However, the information in the FRA relating to SUDS, including through the inclusion of a garden pond is limited, especially on how such a pond, whilst managing general rainwater, would manage or ameliorate risk in [name] 2 in an area at risk of 1 in 100 year risk (+17% climate change) surface water flood event. As such, the appellants proposal for SUDS does not follow the drainage hierarchy set out in Policy SI 13 of the London Plan. Further, the appellant’s flood risk assessment also fails to identify and address other areas of flood risk identified in the Framework, including safe access and escape routes. As such, I find that the proposal does not manage or ameliorate flood risk associated with development in [name] 2.

I note that although the appellant states that they have satisfied the requirement for managing or ameliorating flood risk, they also acknowledge that they believe that a flood risk assessment provided by a specialist agency would be an expense for which the Council could provide assistance. This is not matter for me to consider as part of this appeal and I have considered the proposal on the basis of the appeal documents submitted.

I have considered whether a condition requiring the submission of a flood risk assessment could be attached to any approval. However, It is not evident that flood risk associated with the proposal could be appropriately managed or ameliorated and made acceptable in terms of flood risk. Attaching such a condition would not, therefore, meet the requirement of the National Planning Policy Framework (2024) (the Framework) for making an unacceptable development acceptable through the application of such a condition. Therefore, such a condition would not be reasonable and would fail the tests for conditions set out in Planning Practice Guidance and the Framework.

For the reasons given, I find that the proposal would fail to appropriately manage or ameliorate flood risk in an area designated as [name] 2 and would not accord with Policy CP28 of the [name] (2010), Policies DMD59, DMD60, DM61 and DM62 of the Enfield Development Management Document (2014) and the [name] flood Risk Assessment (2008), [name] 12 and SI 13 of the London Plan 2021 and Section 14 of the Framework. Collectively these seek development, including by extension, be made safe from flood risk for its lifetime, without increasing flood risk elsewhere.

The appeal is dismissed.