Some further thoughts from our Director of Planning and Regeneration Mel Clinton on the national requirement for biodiversity net gain, which is to be a mandatory requirement now that the Environment Act 2021 is on the statute book as law.
It is expected that the net gain requirement will come into effect for planning applications submitted from winter 2023 onward. It will not apply to reserved matters applications for outline planning permissions granted prior to this.
The Broader Context
The provisions of the Act sit within the context of a growing understanding of the need for action to bring about a recovery for nature, following accelerated losses and degradation of habitats. The landmark, Treasury commissioned, Dasgupta Review 2021 summarises the situation succinctly: “We are embedded in Nature; we are not external to it…Truly sustainable economic growth and development means recognising that our long-term prosperity relies on rebalancing our demand of Nature’s goods and services with its capacity to supply them.”
The direct impact of building on development sites is, of course, only part of the picture and by no means the most significant. Development can, however, play an important role in contributing to nature recovery strategies, with related wellbeing and other benefits in terms of the quality of places for the people that live in and use them.
The Net Gain Requirement
All planning permissions will be subject to a requirement to achieve a biodiversity net gain of at least 10%, subject to some likely exemptions that are to follow (e.g. this might include householder development and some types of change of use and brownfield development). Demonstrating net gain will require the submission and approval of a biodiversity Gain Plan. The Gain is to be maintained for a period of at least 30 years, secured by a planning condition, planning obligation or ‘conservation covenant’. This does not override the need that may arise on some sites for biodiversity mitigation measures to be maintained in perpetuity under the Habitat Regulations where there are potential effects on protected habitats.
Measuring Net Gain
The current level of biodiversity and the proposed gain is to be measured using the most recently published Biodiversity Metric – the current one is version 3.0, with a simplified version for small sites. Within the metric there is provision for local planning authorities to take account of baseline site biodiversity degradation occurring since January 2020, in order to help prevent manipulation of biodiversity gain scores.
It is also worth noting that there is conflicting advice and opinion on provision of bat and bird boxes/bricks to help achieve net gain. However, the metric is habitat based and does not appear to score such features – in this respect the Planning Advisory Service states clearly that bat and bird boxes/bricks are not included in net gain calculations. Private gardens are a potentially important habitat resource. However, appropriate planting and long-term management and maintenance cannot be guaranteed, and this is recognised within the metric.
The principal on site measures will therefore comprise creation and conservation of planted habitat areas and linear features.
On-site, Off-site and Credits
The requirements on content of the Gain Plan and the Metric support a hierarchy approach with on-site gain the first priority, followed by off-site and lastly purchase of statutory credits from Government under arrangements to be established by the Secretary of State.
Off-site gain habitat provision is to be secured through planning obligations or a ‘conservation covenant’ and recorded in a national register as required by the Act. Whilst not a legal requirement, discussion is also underway on how on-site gain may also be shown in the register.
Of relevance to off-site gain is the Act’s provision for Local Nature Recovery Strategies, which are to cover the whole of England. These will have a bearing on the suitability of off-site locations and their scoring through the metric, in terms of their relationship to the local strategy.
Getting Ready
The net gain requirement is not entirely new, with the National Planning Policy Framework referencing achievement of net gains and many emerging local plans setting out gain requirements. However, the Environment Act establishes the mandatory 10% requirement across England and specific discipline around how this is calculated and delivered.
As a result, the requirements of the Act bring a number of challenges, not least in getting to grips with the process and subsequent detail that is to be provided through regulations and secondary legislation.
Operation of the system is standardised by the metric but nonetheless requires expertise and, as things stand, resource constraints mean there is a serious deficit in local authority capacity to undertake ecological assessment and monitoring. The increased demand may also cause difficulties for the private sector and other developers in accessing ecological expertise.
Cost is also a potential issue. Whilst the Government has estimated additional costs at 0.1-0.8% for brownfield sites and 0.1-3.9% for greenfield, there remains a significant degree of uncertainty that makes it difficult to factor the costs when establishing land value at site acquisition stage. This applies particularly to off-site solutions and how local markets may develop in respect of land for creation of off-set habitat.
Delay is, of course, always a cost.
It seems wise, therefore,to begin gearing up now for meeting the net gain requirements. In particular, building it into the development process right from the start, considering mechanisms for maintaining habitat over 30 years, ensuring processes are in place for ‘conservation covenants’ where needed and being alert to emerging Nature Recovery Strategies and local markets in off-set land for habitat creation.
Whilst the requirement for biodiversity net gain poses challenges, it also helps underline the merits of adopting a placemaking approach to creating good quality, sustainable environments that integrate habitat, green infrastructure and drainage within the design process, to enhance overall value – environmental, economic and social.