Nutrient neutrality refers to the requirement that nutrient loads in watercourses won’t increase as a result of new developments or land use change. Currently, many of the European and UK watercourses and waterbodies have elevated levels of nutrients, such as nitrogen and phosphorus causing particular problems. The UK government has broadly maintained a commitment in its 2017 manifesto target of 300,000 new homes per year, but the nutrient neutrality issue is currently causing difficulties in planning permission for housing development. Can there be a balance struck between the need for housing and the impact from nutrient-related pollution.
The UK Water Quality Issue
Earlier this year the Environmental Audit Committee released a report on the water quality in UK rivers. They analysed a number of factors, including the cause of water pollution in various areas, the types of pollution and the impact it was having on wildlife and public health. The results are of major concern.
According to the report, most UK rivers currently contain a ‘chemical cocktail of sewage, slurry and plastic’, according to the Committee’s report, which constitutes a significant risk to nature and human health. The report breaks down where the problems are coming from, and this was quite an enlightening section. Some of the biggest contributors to water pollution were the nutrients nitrogen and phosphorus. These particular chemicals can create problems for wildlife as they can cause plants to grow too quickly or die off too fast – disturbing the natural rhythm, as well as dramatically affecting how well water can carry oxygen, which water-dwelling animals and plants need to survive.
The report was only published in January 2022, so the findings and appropriate action are still being discussed. But it has made one thing very clear – the attitude towards water quality needs to change, and harmful nutrients need to be a part of that plan.
Harmful Nutrients and The Housing Market
In terms of water quality, the term ‘nutrients’ refers to the chemicals nitrogen and phosphorus. These are naturally occurring chemicals, and can be released by all sorts of things, like soil erosion during flooding, , wastewater entering watercourses from sewage treatment overflows, surface water runoff from fertilised farmland, or nutrient loads from new housing development. The water environment cannot sustainably tolerate the extra nutrient load we pump into it through development runoff, water treatment and waste.
After a 2018 legal judgement – referred to as the Dutch Nitrogen Cases – Natural England advised planning authorities that granting consent for new housing development could lead to an unacceptable risk to certain European Protected sites from further nutrient release. This position was backed up by subsequent judgements in the UK courts. A significant implication of this is that any development that might lead to increased nutrient releases could only be permitted if it could demonstrate that the additional nutrients would not reach these protected sites – that is, that the developments would be ‘nutrient neutral’. This applies particularly to the building of new houses, which can result in an increase in those two key nutrients flowing into the protected water catchments (whether through sewage treatment works or via private package treatment plants).
As it stands, over 70 planning authorities are required to review nutrient neutrality in determining planning applications, after the wildlife regulator identified a further 20 protected sites that are adversely affected by nutrient pollution and advised that planning applications in affected areas should be very carefully considered. Nutrient neutrality now has to be demonstrated before consent can be granted, which is stalling thousands of projects across affected authorities and may be delaying up to 100,000 homes per year from being built. In some cases, planning may be delayed for up to 2 years, which is having a profound effect on planning consent across a range of industries.
Why Mitigation Is Essential
Natural England now requires developers in 70 local authorities to show that they are not causing additional pollution in protected sites. Some catchments have responded by assessing mitigation. Mitigation is now an essential part of any development planning within the catchments of vulnerable sites. This means that local councils cannot grant any planning permission for projects that will be on or adjacent to those areas until they have carried out an assessment. This includes reviewing developer plans and ensuring they will be ‘nutrient neutral.’ The Government is seeking to address this issue via the Levelling Up and Regeneration Bill, which recently passed its third reading in the Commons and will be reviewed in the Lords in January 2023. If this Bill is enacted as planned in April 2023 it will introduce new and more stringent targets for waste water treatment works that will make it easier for developments to demonstrate nutrient neutrality. In the meantime, dealing with the issue for current planning applications remains complex and often relies on a combination of on-site and off-site solutions.
This applies both to the actual construction phase, and the performance of the development once it is complete and habitable
The best way for developers to manage this complex issue is to include environmental design and mitigation in their planning process. At Engain, we specialise in consultation, assessment and guidance for developers to ensure they are meeting their environmental obligations and having a net positive impact on the environment. We also work with local authorities to help them carry out assessments like nutrient neutrality, so that they can fully understand the environmental issues they are facing and create informed plans for tackling them. If you would like to know more, please get in touch with the Engain team today on 01225 459564 to book your free consultation.