Many organisations and developers are taking positive action in response to the climate and biodiversity emergencies; committing to targets, devising strategies and ringfencing funds to restore and protect natural and cultural heritage, water resources and landscape systems impacted by development. 

The challenge for these organisations is to ensure that environmental spending helps them to meet targets and key performance indicators, while delivering maximum benefits for biodiversity, communities, and the environment.

Restoring the landscape with nature-based solutions

Working with National Highways, Arup has designed Keyn Glas, a landscape scheme alongside the A30 in Cornwall that takes a regenerative approach to land management, restoring habitats and historic landscapes, increasing biodiversity, and reducing the risks of climate change impacts such as flooding.

Funded by National Highway’s Environmental Designated Funds, the scheme aims to look beyond standard road scheme mitigation by addressing and enhancing the wider landscape’s aesthetic, cultural and ecological conditions for generations to come.

Delivering greater impact across the landscape

Arup Explains
What are nature based solutions?
What are nature-based solutions?

The Keyn Glas concept features multiple individual environmental projects on farmland and estates extending up to 3km from the A30. These enhancements include natural flood management, restoration of wetlands and woodlands, and the creation of hedgerows and flower-rich grasslands. While each brings individual benefits, when stitched together across the landscape their impact combines to create an overall scheme greater than the sum of its parts. For example, hedgerow planting provides habitat for pollinating insects and rare and declining birds and mammals which, when connected with other new and existing habitats, creates wildlife corridors and improves the aesthetic and cultural character of the landscape. This manageable approach enabled phase one of the project to go from concept through design to completion within 18 months.

Strategic approach to green and blue networks at a catchment scale
Strategic approach to green and blue networks at a catchment scale
Strategic approach to green and blue networks at a catchment scale (click to zoom).

Restoring connected habitats for biodiversity net gain

While the A30 serves Cornwall’s transport needs, it has also created severance across the landscape. Measures including wildlife crossings and a green bridge will link habitats from either side of the road. Keyn Glas extends these connections into the wider landscape, restoring historic wildlife corridors not seen in Cornwall for generations. Phase one has connected 32 habitat areas across nine farms, resulting in up to 250% net gains in biodiversity, measured using the UK Government’s Biodiversity Net Gain Calculator. The interventions built in phase 1 will also absorb around 10 tonnes of CO2 every year and will contribute positively towards climate change resilience.

Engaging with multiple landowners

The success of the Keyn Glas scheme was dependent on engaging and recruiting landowners who own the land around the A30. Our team worked closely with Cornwall Wildlife Trust to ensure that proposed interventions were locally tailored to complement agricultural practices and enhance farm assets such as field boundaries. This helped gain acceptance for the plans from local farmers and land managers. Close liaison with the Rural Payments Agency (RPA) via Natural England, to agree an approach on a site-by-site basis, ensured proposals were complimentary and did not conflict with existing Countryside Stewardship Agreements.

These projects are a real personal highlight for me. We have been able to work very closely with the local community and restore habitat connectivity that has been severed historically, thus leaving a positive legacy for years to come. The Arup team came up with some great ideas in conjunction with us and the community and crucially understood that the success of these kinds of projects involves bringing local people along with you.

Colin Bird

Programme Leader, Highways England

In return for National Highways providing beneficial works on their land, farmers and landowners have signed bespoke third-party landowner agreements, with a 10-year management period that commits them to taking care of their projects and allowing access for monitoring and maintenance by National Highways. The engagement and partnerships created with landowners and managers has built a strong ethos of community guardianship, so farmers adopt and value their part of the scheme and contribute to the wider long-term benefits for the community.

In recognition of this aspect of the scheme, we were awarded the 'Best Practice: Stakeholder Engagement' award at the Chartered Institute of Ecology and Environmental Management (CIEEM) Awards 2020.

Ensuring a valuable legacy

Together with National Highways, we developed an ambitious and workable design that helped secure environmental funding. The funding was based on measured value for money and included a regular monitoring scheme. Our work on restorative and regenerative land use projects such as Keyn Glas is developing knowledge and contributing to the evidence base for cost effectiveness of interventions that deliver the most valuable and sustainable benefits.

Illustrative view of Central Cornish landscape highlighting lack of recreational access
Illustrative view of Central Cornish landscape highlighting lack of recreational access, sparse vegetation, disrupted wildlife corridors and heritage assets in poor condition.
Illustrative view of interventions after 15 years, helping create a integrated and self-sustaining landscape.
Illustrative view of interventions after 15 years, helping create a integrated and self-sustaining landscape.

The project will leave a legacy of richer, more resilient and diverse ecosystems, and a more beautiful, sustainable and productive landscape for Cornwall. Contributing to National Highways targets to deliver no net loss in biodiversity by 2025, and a net gain by 2040, our design approach and landowner engagement techniques from Keyn Glas are now being used as a blueprint for projects across the country, helping reduce carbon and tackle the impacts of climate change.