Land Studio and nutrient neutrality
In 2019, The European Court of Justice ruled that any additional nutrient loading to what are classed as “designated sites” (particularly ones that were already in an unfavourable condition) would not be permissible by law. This is applicable to Special Areas of Conservation (SAC), Ramsar, Special Protection Areas (SPA) and potential SPA sites.
The current law states that within these catchments any developments must demonstrate that there would be no likely significant nutrient effect on the downstream designated site.
It means that all developments in the affected catchment have to demonstrate what is known as ‘Nutrient Neutrality’. Currently, Natural England rules mean 62 local authorities cannot allow new developments unless builders can prove their projects are "nutrient neutral" in protected areas, including Somerset, Norfolk, Teesside, Kent, Wiltshire and the Solent.
The nutrients, specifically nitrogen and/or phosphorus, from all surface water run-off and wastewater generated by the development must be less than or equal to the nutrients generated by the existing land use.
The requirement ensures that a development does not add to existing nutrient burdens and provides certainty that the scheme is deliverable in line with the requirements of the legislation.
At Land Studio, we’re working on a project within the Wye Catchment near Ross on Wye where, alongside an ecologist, and following Natural England’s advice, we are proposing mitigation measures to demonstrate that the development can achieve nutrient neutrality through adequate treatment of the surface water, treated foul water and reduction in water consumption on site.
Our mitigation measures include sustainable drainage systems with the emphasis on green/blue infrastructure and bioretention to absorb nutrients before they enter the downstream watercourse and protected site.
The introduction of a riparian buffer, a wetland right next to the onsite watercourse and strategically placed rain gardens within the site landscape to filters out nutrient pollution from the upstream catchment are at the heart of our design.