Nutrient neutrality and housing development

In August 2023, the government announced that it would amend the Habitats Regulations which underpin ‘nutrient neutrality’ through the Levelling Up and Regeneration Bill 2022–23. The proposed amendments were rejected by the House of Lords in September 2023.

Nutrient neutrality requires that new housing developments in certain areas should not add more ‘nutrient pollution’ to the water catchment. It applies only to new housing developments in areas with protected habitats sites that are already in ‘unfavourable condition’ (due to nutrient pollution).

The Habitats Regulations

The Habitats Regulations establish protections for sites in England that are important for nature or for protecting threatened habitats and species. The regulations require public bodies, including local planning authorities, to assess the environmental impact of plans and projects on these sites.

Local planning authorities should only consent to developments that will not adversely affect a protected site or ensure any adverse effects are mitigated. They have to seek advice from Natural England, the government body which is responsible for protecting England’s natural environment.

Nutrient neutrality

What are the nutrients of concern?

Nutrients such as nitrogen and phosphorus provide nutrition for plants and animals and are required for them to grow. They occur naturally in ecosystems, but human activities can increase their supply. An excess of nitrogen and phosphorus can be damaging to the environment because it can lead to eutrophication and algal blooms in rivers and lakes.

The main sources of phosphorus and nitrates in rivers and lakes in the UK are sewage effluent and run-off from agricultural land. There is no up-to-date data on the exact contribution of these sources to the nutrient load in UK waters and to nutrient pollution.

Guidance issued by Natural England

Following a ruling by the Court of Justice of the EU, Natural England issued new advice to 32 local planning authorities in England in 2019 and to 42 more in 2022. This highlighted that a number of sites in their areas that were protected under the Habitats Regulations were in ‘unfavourable condition’ due to excess nutrients. Natural England said “extra wastewater from new housing developments” could “make matters worse”.

Natural England therefore advised these local planning authorities that they should only approve new housing developments that are ‘nutrient neutral’. In most cases (where the discharge of nutrients cannot be avoided), nutrient neutrality is achieved by putting appropriate mitigation strategies in place.

Impact on housebuilding

Developers have argued that nutrient neutrality has resulted in delays to new housebuilding. They have said agriculture and water companies should be responsible for tackling nutrient pollution.

Environmental groups have highlighted, however, that nutrient neutrality only applies to areas where excess nutrients threaten habitats and wildlife which are legally protected from harm. They point to the importance of mitigation measures to tackle nutrient pollution.

Proposals to “scrap” nutrient neutrality

In August 2023, the government announced it would make changes to the Habitats Regulations underpinning nutrient neutrality rules. It tabled an amendment to Levelling Up and Regeneration Bill 2022–23 which would have required local planning authorities to assume that nutrients in wastewater from new developments would not adversely affect protected habitats sites.

The amendment was defeated in the House of Lords and not added to the bill. Newspapers have since reported that the government was “drawing up plans for a new bill […] to ditch “nutrient neutrality” rules”.

Reaction to the proposals

The government announcement was welcomed by developers who said the changes would “unlock housing delivery”. It was met with concern by environmental groups, however, who said “scrapping the rules” would come “at the expense of our rivers and the natural environment”.

The Office for Environmental Protection said the changes would “demonstrably reduce the level of environmental protection provided for in existing environmental law”. The government said its reform package would improve environmental outcomes.

Tackling nutrient pollution in wastewater and farming

The government has set out actions to reduce the impact of nutrient pollution on protected sites, including by tackling pollution from farming.

In addition, through the Levelling Up and Regeneration Bill 2022–23, the government would place a new duty on water and sewerage companies to upgrade their wastewater treatment works by 2030 in areas where habitats sites are in ‘unfavourable condition’.