To Stack Or Not To Stack: The Role Of Nutrient Neutrality In UK Ecology – By Cameron Carmichael

We are in a transformative period for the UK ecology sector, characterised by constant change and development.

Over the past few weeks, nutrient neutrality has dominated the headlines, with the government announcing short-lived plans to abandon EU Regulations, to enable the construction of new homes. But with these headlines has come a lot of uncertainty. Ultimately, we need to unpick how we can help our clients move forward, whilst ensuring our most sensitive and ecologically significant sites can recover.

As we have seen with Biodiversity Net Gain (BNG), environmental legislative change tends to be both continuous and non-linear. Although we can’t predict what tomorrow will bring, we can certainly utilise today’s nutrient neutrality policies to secure the best for our clients and the environment.

What is the current process?

Across the country, nutrient pollution, creating algal blooms and eutrophication, poses an urgent problem for freshwater habitats and estuaries. It is primarily caused by agriculture and unplanned sewage discharges, but also by increases in house building and tourism. Over the past 3 years, 74 local authority areas have been impacted, from Cornwall to Northumberland.

Given that housebuilding is a contributor, albeit minor, to the nutrient pollution problem, impacted local authorities now require any planning application which results in an increase in overnight accommodation to be nutrient neutral. Achieving neutrality, however, is not easy and as such, the government introduced a pilot Nutrient Mitigation Scheme in the River Tees catchment, which offers landowners a financial incentive to tackle this issue.

Under the scheme, credits can be created by landowners who reduce or capture nutrients that would otherwise end up in our designated sites. Crucially, these nutrient mitigation credits can also be ‘stacked’ on top of BNG units, allowing landowners to profit multiple times from a single improvement, on a single piece of land.

Stacking is facilitated by the legislative requirements that underpin both metrics. As such, if an improvement has a demonstrable impact on both BNG and nutrient neutrality, it can yield credits and units under both schemes. Additionally, if in the future a landowner can demonstrate a further improvement, beyond the targets initially set and sold, they can stack and sell even more credits and units on the same piece of land.

This process provides a valuable opportunity for landowners to maximise the profitability of a single ecological improvement.

What are the barriers?

When it comes to the stacking and selling of nutrient mitigation credits, it is undoubtedly the lack of certainty that creates the biggest obstacle for landowners.

As the government has recently announced plans to transform current nutrient neutrality regulations in a way that will aid UK house building targets, it seems that the timescale for a finalised scheme may be set to increase.

This update has created a lot of uncertainty regarding the future of nutrient neutrality, and it is this lack of clarity that is stopping landowners from engaging with the current Nutrient Mitigation Scheme.

Adding to this unpredictability is the lengthy sign-up time required under the scheme; while BNG units must be legally secured for 30 years, nutrient mitigation credits demand 125 years of commitment. Understandably, this timescale can initially appear both restrictive and daunting to landowners.

It must also be noted that while BNG units are dictated by a single national calculator, nutrient mitigation credits are subject to the individual requirements of each catchment area. This regional variation can be seen to add an extra layer of complexity to the scheme, and may deter landowners from choosing to engage.

What are the benefits?

There are countless benefits when it comes to the creation of nutrient mitigation credits. At Biodiverse Consulting, we encourage our clients to park their uncertainty and focus on the opportunity available – this scheme provides an excellent means of yielding profit whilst supporting nature. And ultimately, we need to make sure that eligible landowners are aware of its potential.

Despite the regional variation in mitigation requirements, the nutrient mitigation calculators serve as a useful tool to support the creation of credits. For developers, the opportunity to purchase these credits allows them to pursue their development plans and secure planning permission. For landowners, the sale of nutrient credits provides a means of diversifying income through natural capital markets.

The ability to combine nutrient mitigation credits with BNG units should not be overlooked; if a piece of land has the potential to yield benefits under both schemes, this creates a valuable opportunity to maximise the impact of a single change.

Furthermore, the ability to revisit and expand upon a previously implemented change provides landowners with the option to sell additional nutrient mitigation credits, further enhancing the profitability of the land.

Ultimately, whilst legislative change is inevitable, the rejection of the recent amendments to the LURB emphasises the ongoing importance of nutrient neutrality regulations in protecting the UK’s waterways. And, whilst the technicalities of the existing scheme may be subject to amendment, its overarching purpose should not.

How do we move forward?

Working within an ever changing industry means adaptability is paramount.

Shifting our perspective and developing an understanding of the commercial value of current schemes is instrumental if we are to help our clients navigate this changing natural capital landscape.

Whilst ongoing changes need to be carefully navigated, they are opening up an important space for ecology within the planning sector and offering landowners a unique opportunity to financially benefit from nature’s recovery.

As ecologists, embracing these changes and helping our clients use them advantageously represents a huge opportunity for our sector. It provides us with the chance to see positive impact delivered, which is essential in our fight against biodiversity depletion and climate change.

Cameron Carmichael | Ecologist and Nutrient Specialist | Biodiverse Consulting

Newcastle University graduate Cameron is an Ecologist and Nutrient Specialist at Biodiverse Consulting, an environmental consultancy based in Northumberland.

Cameron has delivered sHRA and nutrient neutrality scoping for countless projects, ranging from change of use to 100+ unit developments.

Experienced with BNG, he has also completed his MoRPH5 River Condition Assessment course.

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