On Friday, the Court of Appeal issued a fascinating judgment concerning the correct approach to applying the 2018 version of Natural England's advice on Nutrient Neutrality*. A really helpful summary of the case, R (Wyatt) v Fareham BC & Natural England [2022] EWCA Civ 983, has been produced by Landmark Chambers and can be accessed through the link at the bottom of this post.

The Judgment has particular resonance right now, in the light of Natural England's recent updates to its advice, and its expansion to an additional 42 local authorities in March of this year.

This post is not an attempt to provide a case note on the  judgment, Landmark has already done that and no doubt many other notes will follow.  Instead, I am going to focus on the concurring judgment of Lord Justice Males - which starts at paragraph 117 (or page 36) of the Decision. 

Lord Justice Males judgment is fascinating. He sets out a clear and compelling analysis explaining that a Council can carry out a lawful appropriate assessment despite deviating from the procedure set out in the Natural England technical guidance, where they have a good reason for doing so.  In this instance, that reason was the fact that the Council  had consulted Natural England, making clear that it had used the 2.4 persons occupancy rate, and Natural England had not objected.

I strongly recommend reading the judgment in full. If you are short on time, however, the conclusion - and postscript - are set out below.

 The postscript is worth close attention as it highlights the fact that further variations from the average occupancy rates are now expressly supported in the 2022 guidance. As such, it seems highly unlikely that the Court will interfere with decisions by local authorities to substitute occupancy rates,  provided the rationale for the rates chosen has been properly evidenced.

This could be extremely helpful, particularly in the light of the Lichfields Report, commissioned by the Home Builders Federation, which argues that use of average occupancy figures in the standard assumptions significantly overestimates the likely additional population that would result from the development of new housing. As a result, the amount of mitigation required from each new development is also subsequently significantly overestimated.   

The Home Builders Federation  is using this report to urge local authorities to amend the nutrient calculator to take account of evidence from the official household and populations projections of the net average household size in each area, rather than default to Natural England’s advice 

Lord Justice Males reasoning (below**) is likely to be extremely reassuring to any local authorities who chose to do so. 


146. Despite this, however, I consider that the use of the national average occupancy rate of 2.4 persons per dwelling did not render the “appropriate assessment” carried out by the Council unlawful. The question for the Council was not whether it had followed precisely the methodology set out in the 2020 Advice, but rather whether it had carried out a sufficient “appropriate assessment” for the purpose of the Habitats Regulations. It was not mandatory to follow precisely the methodology set out in the 2020 Advice and the use of the national average occupancy rate was not questioned by Natural England when consulted about the proposed development. Rather, Natural England stated that it had no concerns. That was a view to which the Council was entitled and required to have regard. It provided a good reason not to follow precisely the methodology set out in the 2020 Advice. In those circumstances we can only interfere with the conclusion of the Council, based on the assessment which it had undertaken, that the proposed development would not contravene Regulation 63 of the Habitats Regulations, if that conclusion was Wednesbury unreasonable. That is a demanding test and I am not persuaded that it is satisfied here.

Postscript – the 2022 Advice

147. I would add that we have been provided with the latest version of Natural England’s Advice to planning authorities, issued in March 2022 and updated expressly in the light of (among other things) the judgment of Mr Justice Jay in this case. This Advice is not limited to the Solent region.

148. Interestingly, the 2022 Advice emphasises the importance of local conditions in selecting an occupancy figure, and the need to focus on the particular project being assessed. It recognises that the average national occupancy rate of 2.4 persons per dwelling (which it notes will be subject to change when the results of the 2021 Census become available) may not be appropriate for certain types of development:

“Occupancy rates based on dwelling type Should the nature or scale of development associated with a particular project proposal suggest that the use of an average occupancy rate is not appropriate, then the Local Planning Authority may decide to adopt an occupancy rate based on the dwelling types proposed for that particular project, provided it meets the criteria outlined above …”

Those criteria include that the rate selected reflects local conditions, is sufficiently robust and appropriate for the project being assessed, and is derived from a reliable source which can show trends over a protracted period of time, such as data from the Office for National Statistics.

149. For the future it is the 2022 Advice which planning authorities will need to consider."

*full disclosure - this photo is not of an algal bloom. It is a photo of my local park after a colour run. 

** The underlined sections have been added (by me) for emphasis.