The development of new homes in parts of the UK is facing significant barriers due to the failure to demonstrate sufficient mitigation of nutrient pollution from housing developments.
However, our MD Ross Oakley believes closer cooperation between all those involved in tackling the problem will bring forward those schemes that see local ecosystems under pressure from a range of pollutants from development.
Across the North of England – indeed across whole swathes of the country – many areas are grappling with the concept of how to achieve ‘nutrient neutral’ development. In particular, this can be seen in places where wastewater nutrient outputs from new housing discharge to designated water bodies are currently failing, or are close to failing. The increased build up of nitrogen and/or phosphorous can lead to eutrophication: a process where nutrient overload can result in algal growth within a waterbody with significant impact on a range of aquatic organisms.
The impact on British farming is also significant, as one of the possible solutions is to convert farmland into wetlands and woodlands, which in turn reduces potential farmland and works against the UK objectives to farm and buy domestic produce.
Where a development has been identified as needing to achieve nutrient neutrality, a plan is required to demonstrate that mitigation is significantly robust to meet the stringent European Directive 92/43/ECC HRA process of ‘no likely significant adverse effect’ on natural habitats and wild fauna and flora for Natura 2000 sites.
We are currently seeing plans for nearly 100,000 homes held up by new regulations put in place by environment watchdog Natural England, which advises that no development should ‘add to existing nutrient burdens’ – that is to say, all surface water runoff and wastewater generated by a development must be less than or equal to the nutrients generated by the existing land use.
All well and good you might say, but the impact is acutely felt with huge ramifications. Only recently, the Home Builders’ Federation estimated that plans for a further 36,752 homes are in jeopardy by the change in guidance around water-borne pollutants including nitrogen and phosphates, which increased the number of local authorities affected by the issue from 32 to 74. This is in addition to the estimated 60,000 homes held up in plans by those authorities already affected by ‘nutrient neutrality issues.
Dozens of planning authorities across the country are being forced to halt developments until they are able to guarantee they are ‘nutrient neutral’ and do not exacerbate the issue. The challenge is to design effective solutions to remove the impact of additional nutrients from new developments to protect the environment while building the homes the country needs.
The challenge from an engineering perspective is a tough but surmountable one. It relies on those involved in tackling the issue – from ecologists through to planners and surveyors to civil and structural engineers preparing their SuDs and drainage plans – working together in close harmony and cooperation to ensure effective and competitive solutions are forthcoming that offer workable solutions to the nutrient neutrality puzzle area by area.
Such an approach will undoubtedly contribute to facilitating the release of those existing housing currently on hold, while providing nervous housebuilders with the confidence to bring forward nascent development plans yet to be submitted for planning consent. In this way, such scalable and impactful solutions will see more and more people in ‘afflicted’ areas get the new homes they need and deserve.