Journey

Achieving nutrient neutrality

Step-by-step guide to achieving nutrient neutrality for development in affected catchments. Learn how to calculate your nutrient budget, identify mitigation options, and prepare your planning application.

Construction & Property Starting Updated 3 November 2026

What you will learn

If your development adds homes or other overnight accommodation in a nutrient-affected catchment, the council can grant planning permission only once it is satisfied that the scheme adds no nutrient pollution. This journey takes you through the compliance process step by step.

By the end of this journey, you will understand:

How to confirm whether your site is affected
How to calculate your nutrient budget
Your options for achieving neutrality
How to prepare your Nutrient Neutrality Statement
When wastewater upgrades might help

Confirm whether your site is affected
Nutrient neutrality requirements apply in 27 catchments across England.

What is nutrient neutrality?

Understand why this requirement exists and why it's blocking development.

Nutrient neutrality is a way of showing that a new development will not add to nutrient pollution in a protected site that is already in unfavourable condition because of it. Natural England has issued advice that, for these sites, projects and plans may only go ahead if the extra wastewater from the population growth they bring will not cause additional pollution. Local planning authorities can approve a project only if they are sufficiently certain it will have no negative effect on the site.

The advice rests on the habitats regulations. Excess nitrogen and phosphorus damage the protected sites, so you must show that the nutrient load from your development is offset.

Natural England advice, June 2023

31 habitats sites, across 27 catchments and 74 local planning authorities (wholly or in part)

Legal basis

Conservation of Habitats and Species Regulations 2017

Demonstrated by

A nutrient budget calculation using the Natural England calculator for the catchment

Default occupancy rate in the calculators

2.4 people per dwelling

What developments are affected?

Government guidance on the nutrient neutrality calculators describes the requirement as applying to new residential development. The calculators also cover other types of overnight accommodation, such as hotels. It matters only where your site is in a catchment covered by Natural England's advice.

How to check if you are affected

Contact your local planning authority or check Natural England's published catchment information. The authority can confirm whether your site falls within a catchment where the advice applies. Catchment boundaries are revised from time to time, for example the River Camel and River Eden calculators changed in March 2026.

Nature Restoration Fund and Environmental Delivery Plans

The Planning and Infrastructure Act 2025 provides for Environmental Delivery Plans (EDPs). Under an EDP, a developer pays a nature restoration levy to fund large-scale conservation measures instead of mitigating site by site. On 17 September 2026 Natural England published the first draft EDP, for the River Wensum, Bure Broads and Marshes, and Yare Broads and Marshes catchments in Norfolk, for consultation. Until an EDP that covers your development has been made and you have committed to paying the levy, you must still demonstrate nutrient neutrality for affected developments.
Affected catchments

Full list of the 27 catchments where nutrient neutrality applies.
Natural England publishes a nutrient neutrality calculator for each of 27 catchments in England. A developer must show that new residential development will not add to nutrient pollution in the protected site. Sixteen of the catchments are also designated as sensitive under section 96C of the Water Industry Act 1991, which requires water companies to upgrade the larger wastewater treatment works that serve them.

Catchments with a nutrient neutrality calculator

27

Designated sensitive catchments

16

Wastewater upgrade date

1 April 2030 (designations from 25 January 2024)

Default occupancy rate

2.4 people per dwelling

Nutrient budget buffer

20% added to the final nutrient budget

Calculator download location

GOV.UK - Tools and resources for calculating nutrient neutrality

Catchments by nutrient that applies

Nitrogen only (4):

Lindisfarne

Poole Harbour (designated sensitive for nitrogen and phosphorus)

Solent (designated sensitive for nitrogen)

Teesmouth (designated sensitive for nitrogen)

Phosphorus only (15):

Esthwaite Water

Peak District Dales

River Avon (designated sensitive)

River Axe (designated sensitive)

River Camel (designated sensitive)

River Derwent and Bassenthwaite Lake (designated sensitive)

River Eden (designated sensitive)

River Itchen (designated sensitive)

River Kent (designated sensitive)

River Lambourn (designated sensitive)

River Lugg

River Mease (designated sensitive)

River Wensum (designated sensitive)

Roman Walls Loughs

Somerset Levels and Moors (designated sensitive)

Nitrogen and phosphorus (8):

Chesil and the Fleet

Hornsea Mere

Oak Mere

River Clun

Rostherne Mere

Stodmarsh (designated sensitive for nitrogen and phosphorus)

The Broads (designated sensitive for nitrogen and phosphorus)

West Midlands Mosses

Use the calculator for your own catchment. Each has its own baseline data, and the calculators already allow for the wastewater treatment upgrades.

Parts of some catchments are outside the designation. For example, the designation covers only named parts of the Broads, River Kent and the River Derwent and Bassenthwaite Lake catchments.
Calculate your nutrient budget
You must calculate how many kilograms of nitrogen and/or phosphorus your development will generate, then demonstrate how you'll mitigate this.

The calculation process:
1. Download the catchment-specific calculator from Natural England
2. Input your development details (dwellings, occupancy)
3. Calculate your existing baseline (current land use)
4. Determine the net increase you need to mitigate
Guv’s take

Use the correct calculator. Natural England provides different calculators for each catchment. They contain catchment-specific assumptions and cannot be substituted. Always use the latest version.

Choose your mitigation approach

Once you know your nutrient budget, you must secure mitigation that achieves neutrality.

Natural England mitigation scheme

The credit scheme available in some catchments - how it works and costs.

Natural England sells nutrient credits so that developers can offset the nutrient pollution their development creates and give the local planning authority the certainty it needs to grant permission. Credits are sold continuously, so you can apply at any time. You need a planning application reference first, but not planning permission.

Catchments: Tees and Poole Harbour
Who can apply: Individuals, developers of any size and consultants acting for them
Eligible development: Permanent homes and holiday accommodation, including lodges, cabins and cottages
Credit unit: 1 credit mitigates 1 kg of nitrogen
Deposit: The higher of £182.50 plus VAT or 10% of the credit cost, within 28 days
Provisional certificate validity: 36 weeks; up to 16 weeks' extension; 52 weeks maximum

How to buy credits

Use the current nutrient neutrality calculator for your catchment to work out how many credits you need, and send the result to your local planning authority with your planning application. Then email the application form and your nutrient budget calculation to Natural England. An out-of-date calculator version means your application will be rejected. Credits are allocated to smaller developments (50 units or fewer) and larger ones (51 or more) from separate pots, favouring the applications that support the most homes per credit.

If you are successful, Natural England emails an unsigned nutrient credit certificate. Check it, sign it and return it, and pay the deposit within 28 days or you risk losing the allocation. Send the provisional certificate to your planning authority as proof of mitigation. Tell Natural England within 8 weeks of receiving planning permission, then pay the balance within 28 days to receive the final certificate. Send that to your planning authority, which confirms whether the nutrient condition is met. After that the homes can be occupied.

Prices

The cost of a credit varies between catchments and over time with the cost of mitigation projects. On 28 October 2026 Natural England's guidance gave £2,700 a credit in the Tees catchment and £3,250 in the Poole Harbour catchment. Each price includes the £182.50 plus VAT application fee.

Other sources of credits

Natural England does not advise on where to buy credits. In the Poole Harbour catchment, local authorities such as Dorset Council and private providers also offer mitigation, and you choose the approach that meets your local planning authority's requirements. Natural England sells long-term credits only, which meet both the pre-2030 and post-2030 requirements. Long-term credits run for 80 years from first occupation, or longer if your planning authority requires.

Mitigation options compared

Option	Pros	Cons
On-site mitigation	Direct control, lower ongoing costs	Requires technical expertise, land take
Natural England credits	Simple, guaranteed compliance	Not available in all catchments, cost
Private mitigation schemes	May be cheaper than credits	Due diligence needed, variable quality
Land use change	Permanent mitigation	Requires available land, ongoing management

Understand the wastewater upgrade timeline
The Levelling-up and Regeneration Act 2023 requires water companies to upgrade treatment works in affected catchments.
Wastewater upgrade duty

When upgrades must be complete and what this means for developers.
Section 96B of the Water Industry Act 1991, inserted by section 168 of the Levelling-up and Regeneration Act 2023, requires a sewerage undertaker in England to secure that each nitrogen or phosphorus significant wastewater treatment works in its system can meet the relevant nutrient pollution standard by the upgrade date, and meets it from then on. A significant works is one that discharges treated effluent into a nitrogen or phosphorus sensitive catchment area and is not exempt.

Duty holder

Sewerage undertakers in England

Sensitive catchments

Designated by the Secretary of State under section 96C

Designation notice

Takes effect from 25 January 2024, unless otherwise specified

Upgrade date

1 April 2030 for those designations

Somerset Levels and Moors SPA

Designated from 16 May 2024; statutory upgrade date 16 May 2031; undertaker has committed to 1 April 2030

Exempt works

Capacity below 2,000 population equivalent when the designation takes effect, unless designated otherwise

Nitrogen standard

Total nitrogen not more than 10 mg/l

Phosphorus standard

Total phosphorus not more than 0.25 mg/l

Habitats assessments for planning
Regulation 85A of the Conservation of Habitats and Species Regulations 2017, inserted by Schedule 15 to the 2023 Act, applies where a competent authority, such as a local planning authority, makes a decision on planning permission that requires an appropriate assessment, and the development's wastewater would be dealt with by a significant works. If the decision is made before the upgrade date, the authority must assume that the works will meet the nutrient pollution standard on and after the upgrade date. A direction under regulation 85C can disapply the assumption, and it does not stop the authority having regard to expected outperformance by a works.

Enforcement
The upgrade duty is enforceable under section 18 of the Water Industry Act 1991 by the Secretary of State or, with the Secretary of State's consent, by Ofwat.
The Environment Agency must use its functions, including environmental permits, to secure compliance.
If a works cannot meet the standard by the upgrade date, regulation 9A of the Environmental Damage (Prevention and Remediation) (England) Regulations 2015 treats the excess nutrient pollution as environmental damage that the undertaker must remedy.
Guv’s take

Timeline consideration: Upgrades in most catchments must be complete by 1 April 2030. The Natural England calculators already include the upgrades, which is why your date of first occupation matters to your budget.

Watch for the Nature Restoration Fund

The Planning and Infrastructure Act 2025 (Royal Assent 18 December 2025) creates a Nature Restoration Fund and Environmental Delivery Plans (EDPs). In time, developers may be able to discharge nutrient obligations by paying into a strategic fund instead of demonstrating site-by-site neutrality.

For most plans, using the levy is voluntary, so the per-site neutrality process in this journey still applies unless you choose the levy and a plan covers your site. The first draft plan is for up to 15,780 homes. Check with your local planning authority whether a plan covers your site.
Prepare your Nutrient Neutrality Statement
Your planning application must include a Nutrient Neutrality Statement demonstrating compliance. This should include:
- Completed catchment calculator showing your nutrient budget
- Baseline calculations with assumptions explained
- Details of your mitigation strategy
- Evidence that mitigation is secured (for example, credit purchase or land agreement)
- Any supporting technical information
Nutrient neutrality compliance guide

Complete guidance on achieving and demonstrating nutrient neutrality

Checklist: Before you submit

☐ Confirmed site is in affected catchment
☐ Used correct catchment-specific calculator
☐ Calculated baseline and net increase accurately
☐ Identified mitigation option that achieves neutrality
☐ Secured mitigation (for example, credits purchased or land agreement signed)
☐ Prepared Nutrient Neutrality Statement with evidence
☐ Discussed approach with LPA in pre-application

Official guidance

Notice of designation of sensitive catchment areas 2024 (opens in a new tab)

Publication · DEFRA · England

Using the nutrient neutrality calculators (opens in a new tab)

Natural England · England

Achieving nutrient neutrality

What you will learn

Confirm whether your site is affected

Calculate your nutrient budget

Choose your mitigation approach

Mitigation options compared

Understand the wastewater upgrade timeline

Watch for the Nature Restoration Fund

Prepare your Nutrient Neutrality Statement

Nutrient neutrality compliance guide

Checklist: Before you submit

Official guidance

Next steps

Marketing compliance: PECR and UK GDPR

Set up auto-enrolment for your workplace pension

File your first Self Assessment tax return

Related journeys

Development blocked by nutrient neutrality

SME housebuilder planning guide

Small site planning fast track

Starting a waste business