Dr Des Purdy looks at the Government's ‘Biodiversity Net Gain’ proposals

25th March, 2019

Are the government's 'Biodiversity Net Gains' proposals a sensible national framework to provide more homes and enhance our natural environment? Or a confusing and costly hurdle for developers to overcome which could potentially lead to the loss of local wildlife species and habitats?

The government has recently consulted on new primary legislation proposals setting out the objectives of the Biodiversity Net Gain (BNG) policy for the environment and whether to mandate BNG as part of the planning process. As part of its 25-year Environment Plan, the government has committed to be: "the first generation to leave the natural environment in a better state than it found it". To this end, Michael Gove, the Secretary of State for the Environment, Food and Rural Affairs, issued a public consultation document to assess how best to integrate the government’s commitment to build 300,000 new homes per year by the mid-2020s (as set out in the Housing White Paper) with biodiversity enhancement. “Reassured by a robust biodiversity net gain, local communities could be more confident in accepting development that delivers growth, jobs and amenities, while having a positive impact on local wildlife”, Mr Gove writes in the foreword.

Following closure of the consultation process in February, the government is reviewing how to implement a standardised approach towards biodiversity gains as a result of development. At present, it hasn’t produced definitive guidelines explaining the exact mechanisms to be followed. However, as part of The Treasury Spring Statement issued on 13 March 2019, Chancellor Philip Hammond, confirmed the government's intention to make Biodiversity Net Gain compulsory as part of planning policy to ensure development has a positive impact on wildlife.

The varying approaches of different local planning authorities (LPAs) towards securing biodiversity gains have contributed to confusion and a perceived lack of a level playing field within the planning system. Current policy and practice suggest that in most cases, net gains in biodiversity are achieved by local judgements following a negotiation process, often via Section 106 Agreements. There is an impression that the interpretation and implementation of policy differs between Local Authorities and is frequently subject to requests for additional surveys, all of which inevitably contribute to further delays, frustration and expense for developers.

The government is proposing a single, consistent, national approach. During the consultation it asked for views on whether BNG would streamline the process and give greater clarity and certainty for developers. In addition it asked how to ensure there is flexibility to meet local priorities while maintaining national consistency.

The proposed new system would utilise an existing ‘DEFRA biodiversity metric’ to determine the ecological value of habitats at any given site. A site score is ascribed based on habitat distinctiveness, its current condition and its extent, expressed as biodiversity units. On completion of the development, a minimum improvement of at least 10% is proposed.

Reaction to confirmation that BNG will be made legally compulsory within the planning process from industry bodies, such as The Federation of Master Builders, has been mixed, with concerns raised about the potential for more costs and delays.

Key benefits to developers are identified as certainty and a level playing field resulting from the adoption of a standardised approach to delivering biodiversity net gain across all LPAs in England. It is, however, pointed out that potentially significant delays to developers are likely to arise from the need to familiarise themselves with the intricacies of any new regulations associated with the revised system.

The adoption of this policy raises a number of questions relating to a lack of clarity in the consultation proposals. Environmentalists have raised concerns whether these new proposals might actually permit developments that would otherwise have been rejected, as proposals now offer the opportunity to buy off-site investments as compensation for habitat loss. Without careful governance, this may open the way for local species losses which may have far reaching and unforeseen effects. Another potentially concerning aspect of the DEFRA metric, is the failure to account for individual wildlife species and an admission that no metric will be able to take every detail and characteristic of biodiversity into account or deliver guarantees that all wildlife species will benefit.  All this is despite assurances by the government that net gain for biodiversity should complement and reinforce national planning policy.

Whilst it is laudable that the government continues to strive towards the delivery of net biodiversity gains as a result of development, it is uncertain whether the current proposals will significantly improve the system as far as ecological receptors are concerned. The complexities of individual sites and interpretation of government guidance may ultimately still lead to delays, with the inevitable knock-on increased costs to developers. Conversely, the policy may do little to allay the suspicions of environmental groups of any additional levels of protection for wildlife arising as a result of new development in England.