Nutrient Neutrality

Nutrient Neutrality: Which Calculator Should I Use?

The Norfolk nutrient budget calculator is now available.  You can use it for proposed developments in the Norfolk catchments impacted by Nutrient Neutrality. It provides a rapid calculation of net phosphate and nitrate loadings from developments based on local data.  This includes phosphate and nitrate offsetting calculations for on and off site locations. It can now be used to inform planning applications with regards to NN.

Developments can either use this calculator or the Natural England calculator to find out the nutrient level for your proposal.  If you are located within one of the SAC Catchments or foul drain into one of those Catchments, you will need to submit one or both of the completed calculators in support of your planning application. Your planning application will only be able to proceed if:

  • the proposed development is nutrient neutral; or
  • you have identified appropriate mitigation (to make it neutral) that can be secured and delivered.

With regards to which calculator to choose, the Norfolk specific calculator uses local data to provide an accurate nutrient calculation.  The Natural England calculator is already approved by NE but takes a national approach to NN and does not allow for local relevant data to be taken into consideration.  It will be up to the individual developments to decide which calculator (or both) they decide to use.

To help, the Norfolk calculator contains a help section to assist with the stages of the process and the video provides a step by step guide on how to use the calculator.

Natural England Comments

Natural England have provided written comments with regards to the Norfolk Calculator (PDF) [143KB] (opens new window) .

The area of risk 

New development in the Norfolk catchments impacted by Nutrient Neutrality may increase nutrient at the habitat sites identified by NE as being in poor condition. 

View the Nutrient Neutrality Map (opens new window)

The catchment area has a map of the applicable 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.

More help with the calculator

If you need help to complete either calculator, we recommend using a specialist consultant.  Natural England also offer a Discretionary Advice Service which you could use.

Student and communal accommodation

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.

Last updated: 18/03/2024 11:45:27