Natural England
Nutrient neutrality means that a new residential development will not causeincreased nutrient pollution to specific protected sites.
Developers must usenutrient budget calculations to show that their proposals will not bring about a net increase in nutrient pollution to specific habitats sites. Some local planning authorities also have their own nutrient neutrality calculators which can be used.
The nutrient neutrality calculators are for:
- developers who need to complete a nutrient budget calculation to support a planning application
- local planning authorities who need to understand the mitigation requirements for future development or to assess planning applications
Summary of updates in May 2024
The calculators were updated in May 2024 to:
- reflect the list of wastewater treatment works under a duty to meet specified nutrient removal levels
- reflect updated advice for the Poole Harbour catchment
- correct a small number of minor data errors
27 nutrient neutrality catchments
The table shows the nutrient neutrality catchments, the nutrients that apply and designated sensitive catchments.
A designated sensitive catchment area is one in which the water company must upgrade wastewater treatment works serving a population equivalent of over 2,000 to meet specified nutrient removal levels under the Water Industry Act 1991.
Find out more in theNotice of designation of sensitive catchment areas 2024.
The calculators automatically take the upgrades into account.
| Catchment | Nutrient neutrality applies to: | Catchment designated as nutrient sensitive for: |
|---|---|---|
| Chesil and the Fleet | nitrogen and phosphorus | not designated |
| Esthwaite Water | phosphorus | not designated |
| Hornsea Mere | nitrogen and phosphorus | not designated |
| Lindisfarne | nitrogen | not designated |
| Oak Mere | nitrogen and phosphorus | not designated |
| Peak District Dales | phosphorus | not designated |
| Poole Harbour | nitrogen | nitrogen and phosphorus |
| River Avon | phosphorus | phosphorus |
| River Axe | phosphorus | phosphorus |
| River Camel | phosphorus | phosphorus |
| River Clun | nitrogen and phosphorus | not designated |
| River Derwent and Bassenthwaite Lake | phosphorus | phosphorus |
| River Eden | phosphorus | phosphorus |
| River Itchen | phosphorus | phosphorus |
| River Kent | phosphorus | phosphorus |
| River Lambourn | phosphorus | phosphorus |
| River Lugg | phosphorus | not designated |
| River Mease | phosphorus | phosphorus |
| River Wensum | phosphorus | phosphorus |
| Roman Walls Loughs | phosphorus | not designated |
| Rostherne Mere | nitrogen and phosphorus | not designated |
| Solent | nitrogen | nitrogen |
| Somerset Levels and Moors | phosphorus | phosphorus |
| Stodmarsh | nitrogen and phosphorus | nitrogen and phosphorus |
| Teesmouth | nitrogen | nitrogen |
| The Broads | nitrogen and phosphorus | nitrogen and phosphorus |
| West Midlands Mosses | nitrogen and phosphorus | not designated |
About the calculator
Each calculator has a cover page of instructions and 5 worksheets to complete.
Worksheet 1: Nutrients from waste water
This worksheet calculates the increase in nutrient loading that comes from a developments waste water.
Data inputs needed are:
- date of first occupancy
- occupancy rate
- daily water usage
- number of residential units
- wastewater treatment works name
Data outputs returned: nutrients from waste water.
Worksheet 2: Nutrients from current land use
This worksheet calculates the pre-existing nutrient load from current land use on the development site.
Data inputs needed are:
- catchment
- soil type
- rainfall
- NVZ(nitrate vulnerable zon