Nutrient Neutrality - What's it all about?

In early 2019, Natural England (NE) produced a position statement regarding the determination of planning applications in the Solent Catchment that result in an increase in residential dwellings. The statement effectively ruled that they should not be determined and, in some more recent cases, even validated unless they can demonstrate that they are nutrient (nitrate) neutral.

This position statement has major implications on developments across the UK and sees a further sustainability goal in the ever increasing need to balance environmental benefit with planning and policy objectives.

So where did this come from? Effectively from the Court of Justice of the European Union ruling in the ‘Dutch Nitrogen’ case in November 2018 under the Habitats Directive (Cooperation Mobilisation for the Environment v Verenigin Leefmilieu).

This ruling  has meant greater scrutiny of the water quality of European designated sites across the UK (e.g. the Solent as a Site of Special Scientific Interest). With regards to new developments which result in an increase in residential dwellings, importantly, this issue does not only scrutinize surface water run-off quality (think SuDS) but also foul effluent which is treated by the UK Statutory Undertakers (e.g. Southern Water) and then discharged often to surface water courses (i.e. more houses = more foul drainage = higher outputs of treated effluent).

Whilst this is evidently good news for aquatic flora and fauna, what does it mean in the context of the UK’s overarching strategy to deliver much needed new homes.

Whilst this may sound to some as the next fad diet, efforts to prove nutrient neutrality has come at a huge cost with hundreds if not thousands of applications in a state of limbo which equals several thousands of new homes delayed.

As this position statement is being digested and, hopefully, better understood it has led to Local Authorities all scrambling to see how this fits with their local planning and development policies. Unfortunately this is starting to cause some confusion with Local Authorities developing independent strategies and supplementary policies rather than being centrally advised by Natural England or Central Government.

For example, Havant Borough Council have developed a ‘Nutrient Budget’ based on methodology and advice from Natural England against which proposed developments within the emerging Local Plan are considered to ensure as they come forward that sufficient mitigation measures can be implemented. Whereas, Winchester City Council has called for Central Government to lead the position on this as they claim that there appears to be a conflict in responsibilities on this matter between Natural England, the Environment Agency and water authorities with Natural England advising local planning authorities to be ‘as precautionary as possible’ when the Environment Agency have advised that no further investment is needed to treat wastewater to a tighter nitrogen limit and that wastewater treatment works operate within permit limits.

In the absence of this central lead, Winchester has stated that in the interim it is the role of the applicant to submit all the information necessary to undertake a suitable assessment including a nitrogen budget and suitable mitigation measures.

Clearly this is an emerging and complex issue that is affecting some areas of the UK more than others. However, in the absence of advice from Central Government, local authorities, statutory bodies and industry leaders are developing their own local policies, strategies and approaches which is not yet leading to a consistent robust approach to assessment or mitigation. In my opinion, this issue will continue to emerge until such time that it is tested in the courts after which I suspect local policies will become more aligned.

So what are we doing? Stantec are UK leaders in catchment management modelling and are currently advising Clients on a number of schemes across the UK which are affected by this issue. Therefore, if you feel this issue will arise (or already has) on a proposed scheme, please do not hesitate to get in touch!