How to apply for planning permission

Nutrient neutrality

Alongside all other local planning authorities in Norfolk, the Council has received a letter dated 16 March 2022 from Natural England concerning nutrient pollution in the protected habitats of the River Wensum Special Area of Conservation and the Broads Special Area of Conservation and Ramsar site. The letter advised that new development within the catchment of these habitats comprising overnight accommodation has the potential to cause adverse impacts with regard to nutrient pollution. Such development includes, but is not limited to:

  • new homes
  • student accommodation
  • care homes
  • tourism attractions
  • tourist accommodation
  • permitted development (which gives rise to new overnight accommodation) under the Town and Country Planning (General Permitted Development) (England) Order 2015
  • any development not involving overnight accommodation, but which may have non-sewerage water quality implications

The Conservation of Species and Habitats Regulations 2017 require local planning authorities to ensure that new development does not cause adverse impacts to protected habitats such as the Broads prior to granting planning permission. At present there are no identified mitigation solutions available locally to resolve these impacts. 

The Council as the Competent Authority cannot lawfully grant planning permission unless it can conclude that development within the catchment of the Broads Special Area of Conservation and Ramsar site will not have an adverse effect.  This process is considered through a Habitats Regulations Assessment.

Guidance on the Habitats Regulations Assessment can be found here.

What does an applicant need to do to demonstrate nutrient neutrality if their development is affected?

  • You will need to calculate the level of nutrients arising from your development and in order to help you to do this you can use the published calculator which has been drafted by the Norfolk Authorities.  Tools are set out in the relevant section below.
  • Once you have established your nutrient impact you will need to identify mitigation.  The Council will not be able to lawfully grant permission unless deliverable mitigation to address those impacts is identified and secured.  See below for an update on national and local work on mitigation strategies.
  • An applicant will need to submit a shadow Habitats Regulation Assessment (HRA) to the Council assessing the impacts and identifying appropriate mitigation and its management and maintenance to demonstrate there are no adverse effects on the integrity of the protected sites.
  • Natural England offers a Discretionary Advice Service which can be used by developers to seek advice on specific schemes.
  • The Council wants to work positively with you however will be unable to positively determine these applications until the mitigation is identified and addressed through the HRA.  Case Officers will therefore seek appropriate extensions of time for the determination of the application to enable you time to continue to address this matter.

Nutrient Budget Calculator tools

Norfolk Authorities have produced a Norfolk Nutrient Budget Calculator which can be used as an alternative to the Natural England Calculator tool.

Read Natural England's response to the Norfolk Nutrient Budget Calculator.

In relation to the use of Natural England Nutrient Calculators and the Habitats Regulations process, the Court of Appeal decision in R (Wyatt) v Fareham BC and Natural England was issued on 15 July 2022.  This confirms that Local Planning Authorities can rely on the guidance of Natural England via their nutrient calculator tools.  However, these are not the only tools that can be used when calculating nutrient loading, they are merely one way of carrying out an “appropriate assessment” and their use is not therefore mandatory. However, the Court of Appeal decision suggests that a planning authority ought to follow the methodology suggested by the statutory nature conservation body unless it has good reason not to do so.  

Natural England published a calculator tool alongside their letter of the 16th March 2022. View full details of the advice received from Natural England and the methods for calculating the nutrients generated by proposals.

Norfolk Nutrient Budget Calculator

The Norfolk Nutrient Budget Calculator can be used for proposed developments in the Norfolk catchments impacted by Nutrient Neutrality.

This is a Norfolk specific calculator, we know other calculators are available including the Natural England Calculator.  The Norfolk Calculator however uses local data to provide a more refined nutrient calculation having regard to specific local characteristics. A new version of the calculator was published in March 2023. This version fixes minor bugs found in the previous version, highlights that the post 2030 figures are for guidance only until the Levelling Up and Regeneration Bill is passed into legislation and now includes a section for student accommodation. 

The Norfolk Calculator provides a rapid calculation of net phosphate and nitrate loadings from developments.  This includes phosphate and nitrate offsetting calculations for on-site and off-site locations. It is a clear decision making tool for the Local Planning Authority and developers.

The calculator is made up of the River Wensum SAC and Broads SAC Nutrient Budget Calculator and the Norfolk Nutrient Budget Calculator Technical Report.  It contains a help section to assist with the stages of the process.  

View the calculator

This video also provides a step by step guide on how to use the calculator

The area of risk

You can see the catchment area by using the following map. Alternatively you can view copies of the maps in the documents section.

The catchment area map has identified the areas served by various wastewater treatment works  WwTWs).  Please note:

  • That we cannot guarantee the accuracy of the WwTW data and you should contact Anglian Water for further information.
  • Developments within the catchment area that will drain to a WwTWs within the catchment will need to complete stages 1-3 of the calculator.
  • Developments located outside of the catchment area but that will connect to a WwTWs that drains to the catchment should not complete Stages 2 and 3.
  • Where a site is located within the hydrological catchment but drains to a WwTWs outside of the catchment then mitigation is not required.
  • The mapping was updated 10 Jan 2023 (Nutrients Catchment Map) to correct the WwTW catchment for Poringland meaning that this area drains into the catchment – please ensure you are using the updated version when assessing schemes in this area.

More help with the calculator

If you need help to complete the calculator, we recommend using a specialist consultant.  

We will be adding more guidance to help use the calculator in response to queries we receive.

For Student and communal accommodation, it is recommended that you calculate average daily total water consumption for the development and enter this into stage one.


In July, the Government issued further information about Nutrient Neutrality and steps to be taken to assist with the delivery of mitigation schemes to help enable development to proceed. Mitigation schemes within the affected areas will be necessary to enable further development such as housing growth to be permitted. 

Written Ministerial Statement made by George Eustice (Secretary of State for Environment, Food and Rural Affairs) was issued on 20 July 2022 

This sets out that the government will: 

  • place a legal duty on water companies to upgrade wastewater treatment works by 2030 in nutrient neutrality areas 
  • require Natural England to establish and deliver a Nutrient Mitigation Scheme 

The government advice was followed by a letter about nutrient neutrality and habitats regulations assessment from Joanna Averley (Chief Planner) issued 21 July 2022. 

The Norfolk Authorities are working together to ensure consistency of approach on Nutrient Neutrality.  The contents of the Written Ministerial Statement and Chief Planner letter are therefore being considered carefully to establish whether this provides a basis for enabling permissions to be issued now with conditions/restrictions or, whether there is a need to wait until there is better understanding of mitigation schemes to be delivered by Natural England and confirmation that those schemes are deliverable.  Further updates will be provided once clarity has been established. 

Royal Haskoning are continuing with their work on behalf of the Norfolk Authorities which includes the development of a bespoke nutrient calculator for the Norfolk catchments. They are also supporting the authorities in the identification of mitigation solutions for the short, medium, and long term. In this respect, Royal Haskoning have prepared the Norfolk Nutrient Mitigation Solutions Report for the Norfolk Authorities. This document is published below:

Norfolk Nutrient Mitigation Solutions Report for the Norfolk Authorities

The work being carried out by the Norfolk Authorities on mitigation does not preclude developers seeking their own mitigation solutions.

Will the Council be offering credits to offset nutrients and will these be available to applicants to purchase?

A number of Norfolk’s Local Authorities together with Anglian Water have set up a not for profit Joint Venture Company (known as Norfolk Environmental Credits) in order to tackle the issue of nutrient neutrality by trading nutrient mitigation credits and enable building work to resume. 

The Joint Venture (JV) has been established as a not-for-profit company and we currently intend to soft-launch the website by the end of April. It will initially seek interest from developers regarding whether they will want to purchase credits in the future and/or whether landowners (and other parties) want to sell nutrient mitigation arising from projects to the JV. However there will not be credits available in the immediate period following the launch.  A JV manager has been appointed and a website will accompany the launch.

It is the intention that there will be some credits available in the Summer (2023) however there will not be sufficient credits for all schemes currently held in the planning system at this time.  Over the following months the availability of credits will increase and the JV will continue to work hard to develop mitigation schemes.  It will be for the JV to administer and allocate credits and not the Local Planning Authority.

What does the launching of the Joint Venture mean for the timescale for my pending planning application? 

Where applicants are awaiting the Norfolk Environmental Credits there is currently no guarantee credits will be available for all schemes in the near future nor a guarantee of their timing.  Applications cannot be determined until appropriate mitigation is secured and the Habitats Regulations satisfied.  The Local Planning Authority will therefore be seeking a further 6 month extension of time on such applications which is reasonable given the likely availability of credits.  We will of course determine the application prior to this where satisfactory mitigation and a satisfactory HRA is concluded in advance of this extension of time.

Addressing Phosphorus only for rural small scale discharges (less than 2m3/day – typically less than approx. 5 dwellings) where there is no connection to mains foul

This report and mapping relates to those sites in rural areas where there are no riparian routes to watercourses, where connection to mains foul is not possible, where Package Treatment Plants or Septic tanks (small discharge up to 2m3/day directly to ground) are proposed, where specific criteria are met (see a - h below) and to assist in concluding no likely significant effects in respect of Nutrient Neutrality from Phosphorus only. Anyone seeking to utilise this methodology should be aware that this does not deal with Nitrates which will also need to be mitigated and HRA demonstrated.

The Norfolk Authorities have commissioned a report (Royal Haskoning small scale discharges of Phosphorus: Low Risk Mapping) which follows and builds upon previously agreed interim guidelines between Natural England and Local Planning Authorities regarding small scale thresholds within the hydrological catchments of areas subject to nutrient neutrality guidance.

The guidance relates to small discharges from Package Treatment Plants (PTPs) and Septic Tanks (STs) of less than 2m3/day directly to ground and it states that where all of the requirements of pre-defined conditions are met, a PTP / ST will not have a likely significant effect on the designated site from phosphorus. The small scale thresholds only applies to phosphorus and not nitrogen, which is a more mobile nutrient.

Criteria a – h need to be satisfied for this approach for Phosphorous to apply.  Details of these conditions can be found at paragraph 2.2 of the report (link below)

A small sewage discharge low risk zone map has been created to support the identification of areas where small scale discharges for Phosphorus may be acceptable.   The map defines the areas which fall within the low risk zone where all of the requirements of conditions a, b, c, d, e and g are met.

Conditions f and h require site specific information and when provided alongside the mapping can be used to demonstrate that all the required conditions are met.

Where all of the conditions (a to h) are met then Natural England can advise that, in its view, a conclusion of no Likely Significant Effects alone and in combination for phosphorus can be reached in these circumstances.  However, nitrogen mitigation will still be required.

In order for a PTP / ST to be accepted, it is expected that a technical report would need to be submitted which shows the location of the PTP / ST within the low risk zone and any supporting evidence to demonstrate conditions f and h are met.

The PTP / ST must also be able to achieve the appropriate Building Regulations requirements. The building regulations state that a connection to the foul sewer should be considered to be potentially feasible where the distance from the development site to the sewer is less than the number of properties multiplied by 30m. In addition to Planning Permission and Building Regulation approval, an Environmental Permit from the Environment Agency may also be required.

The following resources are relevant to Small Scale Discharges of phosphorus and should be fully read and applied.  The above is a summary only of the requirements.

You can also see answers to frequently asked questions.

Copies of the slides from the Agents Forum are also available.