Bob Edmonds describes how considering offsets during environmental impact assessments (EIAs) and in the planning system can help prevent biodiversity loss
Biodiversity offsetting is an approach to compensate for the residual adverse impacts associated with a development that, along with other forms of mitigation, has the aim of achieving no net loss, or even a net gain, for biodiversity.
Moving from net losses to net gains for biodiversity is a central plank of the government’s new sustainable development agenda, which is now enshrined in the national planning policy framework (NPPF) in England.
The commitments in the NPPF are supported by strong government policy commitments in the 2011 natural environment white paper, which is in turn backed up by the evidence reviewed in a 2010 report to Defra entitled “Making space for nature”.
The arguments are compelling. Unless we reverse the decline in our natural capital we will be left with a landscape that is less able to support the services we rely on, including resilience to climate change and flooding, and provision of food and water resources. We will also see declines in species diversity, increasing fragmentation and isolation of our wildlife sites and a reduction in the availability of wildlife-rich spaces for people to enjoy and experience.
Biodiversity offsetting is seen as a useful tool to assist developers to deliver on the government’s sustainable development policy and, in many cases, an EIA is the most appropriate place to document these commitments. SLR is at the forefront of delivering biodiversity offsets though EIA in the UK and describes here a case study which illustrates the principles of biodiversity offsetting and outlines the methods used to calculate biodiversity loss/gain balance sheets.
Biodiversity offsets v compensation
Offsetting differs from standard approaches to biodiversity compensation mainly in respect to the rigour with which the contribution to and losses of biodiversity are measured. The Business and Biodiversity Offsets Programme provides 10 guiding principles for offsetting, which are reflected by Defra’s own guiding principles document, published in July 2011. In addition to these principles, Defra published a tool, or metric, for the measurement of biodiversity offsets in its recently updated technical paper.
Bardon Hill Quarry southern extension
In May 2011, a 66 hectare, 50-year operational extension to Aggregate Industries’ Bardon Hill Quarry was approved by Leicestershire County Council. The new quarry is part of a 512 hectare estate, including the existing quarry, historic parkland, low-intensity agricultural land, various local wildlife sites and a site of special scientific interest.
The EIA included comprehensive ecological baseline studies and ecological impact assessment. Although a comprehensive mitigation package was prepared, the scale of the proposed land-use change meant that the EIA identified residual impacts to local wildlife sites, hedgerows, semi-natural grasslands, birds and terrestrial invertebrates. Therefore, a package of biodiversity offsets was designed by SLR, which included:
- a 25-year commitment to biodiversity management within the Bardon Estate;
- the biodiversity-led restoration of on-site overburden tips; and
- beneficial management of the nearby Ratchett Hill, a degraded lowland heathland site within operator’s ownership.
SLR and The Biodiversity Consultancy field-tested Defra’s proposed offset metric for the Bardon Hill project using data collected for the EIA. The full results were published in December 2010 in the Institute of Ecology and Environmental Management’s journal In Practice (vol 70).
This offset analysis illustrated that no net loss or net gains would be achieved for the majority of habitat types over the 25-year timeframe used. A notable exception was a net loss of hedgerows, which were not replaced on a like-for-like basis due to consideration of the local landscape character of the restored site. In this instance, a “like-for-not-like” offset, the creation of scrub and woodland, was considered appropriate.
Biodiversity offsetting – pilot areas
In November 2011, the UK government published a list of six pilot areas, where partnerships of local authorities, developers and landowner or land managers aim to work together to test the biodiversity offsetting approach.
The pilots will develop a body of evidence that the government will use to decide whether to support greater use of biodiversity offsets in England, and if so, how to use it most effectively.
The pilot areas are:
- Devon
- Doncaster
- Essex
- Greater Norwich
- Nottinghamshire
- Coventry, Warwickshire and Solihull
The government’s clear policy commitment to a presumption in favour of sustainable development puts considerable pressure on EIA professionals to rigorously assess the effects of proposed developments to ensure the key principles of environmental sustainability can be met.
Without this rigour, there is a real risk that this push for growth could have a long-term detrimental effect upon our environment, with consequential impacts on human quality of life and biodiversity.
This article was written as a contribution to the EIA Quality Mark’s commitment to improving EIA practice.
Bob Edmonds is a principal at SLR Consulting and a Chartered environmentalist with thirteen years experience in applied ecology, impact assessment and environmental policy research. He has a long-standing interest in biodiversity offsetting and is a member of the Business and Biodiversity Offsets Programme advisory group.
