News & Insights

A Masterplanner’s Approach to Biodiversity Net Gain


As a multi-disciplinary practice, with extensive experience of taking developments from inception through to implementation, it has always been one of our key objectives to create sustainable developments, which not only have a distinct sense of place, but which also accommodate wildlife, as well as people.

At the outset of any project, be that a feasibility study or a detailed planning application, our Urban Design team always works closely with our ecologists and landscape architects to identify the opportunities and constraints presented by a site, and the most efficient way in which they can be accommodated. We always seek to maximise opportunities for habitat creation, (for example by including more diverse wildlife habitat) in association with SUDs features or within areas of recreational open space.

It is one thing to create new habitats, but they will only be successful if they are properly managed in the future. We have extensive experience in overseeing the implementation of our designs and preparing management plans for their future maintenance.

With Biodiversity Net Gain (BNG) on the way to becoming a statutory requirement, it is critical to consider it at every stage of the planning process. As we act for a broad range of land promoters, house builders and infrastructure providers, we understand the need to provide clear, accessible advice, which allows our clients the opportunity to fully consider the implications of BNG. Our masterplanners, in collaboration with other in-house specialists, provide a key role in drawing all these threads together. They do this throughout the planning process.

Land acquisition

Prior to developers purchasing, or taking an option on land, it is more important than ever to understand the biodiversity value of the habitats, what options may be available for on-site biodiversity enhancement, or whether off-site measures are likely to be required. By working closely with our ecologists, and our other in-house disciplines, our masterplanners can give initial advice on how this will affect the potential developable area of the site.

Promoting land through the Local Plan

If sites are being promoted for development at the review stage of a Local Plan, it is important to fully understand the implications of BNG on the development potential and capacity of a site. By bringing all the disciplines together, the Urban Design team can demonstrate how BNG has been accommodated and is policy compliant.

Outline and detailed planning applications

As we work for most of the leading house builders in the country, we fully understand the need to develop sites efficiently while at the same time creating attractive environments in which to live. By having the in-house capability to show how BNG has been accommodated in designing a development, and the mechanisms for delivering and managing it in the future, we can demonstrate that BNG has been considered from the project outset. Our ecologists are highly skilled and well-versed in assessing habitats and calculating the appropriate biodiversity scores: we can smoothly guide the wider design team through this iterative process to achieve the best possible outcome.

Looking back at some of our historic projects, the following examples provide a flavour of how we have collectively taken schemes from inception, through to implementation, and the way we have created attractive places, in which residents and wildlife can live in harmony. In the emerging era of mandatory Biodiversity Net Gain, this type of approach to placemaking will be critical, and our teams at CSA are perfectly placed to tackle the challenge.

Easton Anton, Andover, Hampshire

The new neighbourhood at East Anton is divided into three parts; Augusta Park, The Chariots and Saxon Heights, and will consist of 2,850 homes with associated facilities and infrastructure when completed. Having originally promoted the site through the Local Plan we then formulated the masterplan and landscape strategy, amongst other things, to support the outline planning application. From those early days we have played a major role in designing and overseeing the implementation of the landscape scheme, which includes the creation of significant areas of amenity open space as well as new wildlife habitats.

It is gratifying to visit the neighbourhood today, now that the landscaping is established, to see how it not only creates an attractive setting to the development but also draws in residents and wildlife from the surrounding area.

North East Crawley, West Sussex

The North East Crawley development comprises several thousand dwellings, as well as supporting community infrastructure, such as schools, employment areas, local centres, and recreational open space. We have been involved with the site for many years, having initially prepared the masterplan, DAS, Landscape Chapter of the Environmental Statement, and other documents to support the planning application. We also represented our clients, Taylor Wimpey and Persimmon, at a public inquiry where we successfully achieved planning consent.

When masterplanning a new development, our approach is always to identify the key landscape features of the site and to use these to add to the sense of place. We also seek to maximise certain aspects, such as SUDs features, that others may see as a constraint, and use these to enhance the development, for both residents and wildlife alike.

Stockbridge Meadows, Cambridgeshire

It’s not only on major development sites where we seek to create BNG but on smaller sites too.

Stockbridge Meadows is a 13-acre site that was gifted to Melbourn Parish Council as part of a scheme for five executive houses on the edge of the village of Melbourn in Cambridgeshire.

As part of the scheme, we created a local wildlife site that provides a mix of habitats, including meadows, ponds, scrub, and orchards, that are now home to lizards, grass snakes, and butterflies, amongst other creatures.

The district council’s planning portfolio holder said: “Sites like Stockbridge Meadows are important for residents, giving them the opportunity to appreciate and become involved in conservation work and encouraging communities to socialise.”

Would you like to know more about Biodiversity Net Gain? Get our free guide here.