Check if nutrient neutrality affects your site

Affected catchments and local authorities

The following 27 catchments currently require nutrient neutrality:

How to check your site

Step 1: Contact your local planning authority

Your LPA is the definitive source. They will confirm:

• Whether your site is in an affected catchment
• Which protected habitats site applies
• Whether nitrogen, phosphorus, or both require neutrality
• Any local mitigation schemes available

Step 2: Check Natural England's catchment maps

Natural England publishes maps showing the boundaries of affected catchments. These are available on GOV.UK and help you identify which catchment your site drains to.

Step 3: Understand your drainage

Nutrient neutrality relates to where your wastewater ultimately discharges. Key questions:

• Where does your site connect to for foul drainage? Identify the receiving wastewater treatment works.
• Where does that works discharge? The receiving watercourse determines which catchment applies.
• Are you proposing private treatment? If using a package treatment plant, where will it discharge?

What if you're on a catchment boundary?

If your site is near a catchment boundary, the determining factor is where your wastewater flows, not where your site sits geographically. A site physically outside an affected catchment but draining into it will still require nutrient neutrality.

Development types affected

Most affected:

• New residential development (any size)
• Agricultural building conversions to residential
• Student accommodation
• Care homes and nursing homes
• Hotels with overnight stays

Less affected:

• Commercial development without significant wastewater (warehouses, storage)
• Extensions not increasing bedroom numbers
• Replacement dwellings with same bedroom count
• Agricultural buildings remaining in agricultural use

Note: Even "less affected" development types should be checked with your LPA. Local interpretation varies.

If your site IS affected

You will need to:

1. Calculate your nutrient budget using Natural England's catchment-specific calculator
2. Identify mitigation to achieve neutrality (on-site, off-site, or credits)
3. Prepare a Nutrient Neutrality Statement for your planning application
4. Submit evidence of secured mitigation with your application

See Nutrient neutrality compliance for development for detailed guidance on achieving compliance.

Upcoming alternative: 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), under which developers may eventually discharge nutrient obligations by paying into a strategic fund instead of demonstrating site-by-site neutrality.

This mechanism is enacted but not yet operational: as of mid-2026 no EDP is in force, so the per-site nutrient neutrality requirement described above still applies. Natural England has notified an intention to prepare nutrient-pollution EDPs, expected to be consulted on during 2026. Check the current position with your local planning authority.

If your site is NOT affected

If your site is outside affected catchments, you do not need to demonstrate nutrient neutrality for planning purposes. However:

• Check for other environmental constraints: Your site may still have biodiversity, flood risk, or other environmental requirements.
• Catchments can be added: New scientific evidence may designate additional catchments in future.
• Development in currently unaffected areas is welcome: LPAs outside affected catchments are keen to process applications while nutrient-affected authorities are constrained.