A planning judgement of significance

I don't often write on the ramifications of a single piece of caselaw. However, it is not often that the Supreme Court delivers a planning judgement of such wide-ranging potential significance as this – Hillside Parks Ltd (Appellant) v Snowdonia National Park Authority (Respondent). Will this case become as frequently talked about as Wheatcroft, or Powergen or as significant in its time as Dover v CPRE or Cala? A top five for the decade? Let's see.

From my reading and an overnight pool of the various comments already being made on this case, the Supreme Court reaffirms or confirms the following key points:

1. We do not accept that ... there is any principle in planning law whereby a planning permission can be abandoned.
2. Where planning permission for a multi-unit development is applied for and is granted; it is granted for that development as an integrated whole. From a spatial point of view, a planning permission to develop a plot of land is not severable into separate permissions applicable to discrete parts of the site. 
3. A planning permission is not granted conditional upon completion of the whole scheme of development covered by the permission. The statute itself imposes no condition precedent or subsequent that the authorisation granted be implemented in full.
4. Carrying out under an independent planning permission on any part of a multi-phase development which departed in a material way from that scheme would make it physically impossible and hence unlawful to carry out any further development under the original permission.
5. Despite the limited power to amend an existing planning permission, there is no reason why an approved development scheme cannot be modified by an appropriately framed additional planning permission which covers the whole site and includes the necessary modifications. The position then would be that the developer has two permissions in relation to the whole site, with different terms, and is entitled to proceed under the second.
6. If an application for a permission described as a 'variation' is properly to be analysed in this way, ordinarily it would have to be accompanied by a plan which showed how the proposed new permission incorporated the changes indicated into a coherent design for the whole site.
7. Where an application for a variation of a previous permission is properly to be regarded as an application for a fresh permission for the whole site, this may of course mean that the application is required to be accompanied by certain documentation relevant to the whole site, such as an environmental impact assessment. Where the variation is comparatively minor and circumstances have not changed, it may be possible to re-use or update such documentation submitted in support of the application for the previous permission. Whether this is possible or not will depend upon the particular circumstances.
8. It is possible in principle for a local planning authority to grant a planning permission which approves a modification of such an entire scheme rather than constituting a separate permission referable just to part of the scheme. The developer has failed to show, however, that the additional planning permissions under which development has been carried out on the Balkan Hill site since 1987 should be construed in this way.

No doubt much commentary on the ramifications of this will follow. In my view there are practical difficulties with the way the cookie has crumbled in the Supreme Court this week. As Charlie Banner KC submitted, there remains a practical inconvenience if a developer who, when carrying out a large development, encounters a local difficulty or wishes for other reasons to depart from the approved scheme in one particular area of the site.

At the lesser reading of this judgement, greater care will need to be taken that such variations are properly presented as part of the whole. In some instances, these principles will prevent a flexibility some developers and LPAs had previously worked to via the colloquially known 'slot/drop-in' application. It is not the end to that short-cut, but it will require a full analysis on each occasion it is sought to be used.