Aysen Dennis, R (on the application of) v London Borough of Southwark

The recent High Court judgment has important implications for the interpretation of planning permissions and use of 'drop in' permissions following Hillside (learn more in our article here). It confirms that an outline, phased permission is not inherently severable.

Whether a permission is or is not severable, and can be amended by a later 'drop in' permission, will depend on whether this was intended when the permission was granted and the extent to which this is clear from the permission itself. Going forwards, if severability is intended, it must be designed into the scheme and made clear on the face of the permission and in the supporting documents.

Why did this case come to court?

On 28 March 2023, the London Borough of Southwark (Southwark) granted Notting Hill Genesis (NHG) a non-material amendment to an outline planning permission for the phased redevelopment and regeneration of the Aylesbury Estate in south-east London (the OPP), comprising of 2,745 new homes across an area of 22 hectares divided into three phases.

The amendment, made under s.96A of the Town and Country Planning Act (TCPA 1990), inserted the word “severable” into the description of the development of the OPP, to read as a permission for a "severable phased development". The intention was to allow NHG to implement a "drop-in" permission but still be able to rely on the original OPP to complete later phases of the development. NHG argued that the amendment made under s.96A was only intended to confirm, explicitly on the face of the OPP, that it was severable.

A local resident and campaigner whose home was due to be demolished under NHG's scheme argued that the s.96A amendment was 'material' and therefore outside the power contained in s.96A. It was submitted that the OPP: 

"was granted for the scheme integrated as a whole, with interconnected and interdependent constituent parts. It was not granted on a 'mix and match' basis, allowing the developer to implement another permission so as to insert, or 'drop in', a phase physically incompatible with the OPP and yet still be able to rely upon the OPP for later phases". 

The issue the court had to consider

The question for the court was whether the OPP was severable (in which case the amendment would be non-material), or whether the OPP was not severable (in which case the amendment would be material and outside the realms of s.96A).

The judgment

The Court did not agree that simply calling something 'severable' would have the effect of making it 'severable' if it had not been designed to be severable from the outset. Having considered the OPP as a whole, including the incorporated documents, the Court came to the conclusion that the OPP was not 'severable'.

Why is this judgment important?

This judgment has implications for the lawfulness of so called 'drop-in' permissions and it is the first case to apply the Supreme Court’s ruling in Hillside Parks Limited v Snowdonia National Park Authority [2022] 1WLR 5077 to an outline planning permission to be developed in phases.

In this case the s.96A amendment had been sought to facilitate a 'drop-in' permission. As well as implementing the 'drop-in' permission, the developer wanted to develop the remainder of the Estate under the original OPP.

The problem was that Hillside confirms that unless it was explicit that a planning permission was severable, then it should be assumed that further development under the permission is not permitted if compliance with the permission becomes physically impossible. Applying the ruling in Hillside to this case, it meant that, unless the original OPP was 'severable', the developer would not be able to lawfully continue developing the site under the original OPP if a new 'drop-in' permission had been granted and implemented.

The Court clearly rejected the argument that just because the OPP was outline and for phased development it was inherently 'severable' in its nature.

The OPP was held to be granted for the scheme integrated as a whole because:

  • The officer's report considered a range of factors relevant to the proposed development taken as a whole
  • The OPP incorporated documents which referenced the integrated nature of the "comprehensive regeneration" of the Estate, with "connected neighbourhoods" and a "degree of continuity and consistency across the …… area of the Estate"
  • The parameter plans, which were a requirement for the delivery of phases, did not amount to a 'clear contrary indication' that the OPP was severed into discrete permissions and were compatible with the OPP being treated as a single planning permission.

This case illustrates how important it is that great care is taken when preparing planning applications particularly for complex large scale multi-unit schemes. 

If future severability is to be an option, then at the time of the original grant, severability of the permission should be made explicit in the description of development, and reflected throughout the application documents.