National Highways is applying the finishing touches to its A30 dualling project in Cornwall after planting up its green bridge.

As part of the major A30 Chiverton to Carland Cross upgrade, a dual-deck bridge has been constructed by contractors Costain over the new carriageway, and following top soiling work last summer, the structure at Marazanvose is now taking on its green appearance following tree planting just before Christmas.

Landscaping has seen the planting of two native hedgerows, with species including hazel, hawthorn, holly, dog rose, elder and wych elm, along with hazel and hawthorn trees and seeding of grasses and wildflowers.

Further seeding and planting will take part in the spring, and once completed, the green bridge will cater for a different type of traffic, providing a flourishing green crossing and a safe passage across the road for various wildlife species, including badgers, voles and other small animals, insects and birds.

The bridge – 49.3 metres in length and 12.5m wide – spans four lanes of the new dual carriageway and two lanes of the old A30, now the B3288, and will not only provide better connectivity for wildlife but also farm access and a bridleway for horse riders.

There are only a handful of green bridges across the country and for National Highways, it represents the third such structure to be built across the Strategic Road Network, and a second for Cornwall following the A391 Carluddon road bridge.

The company, responsible for England’s major A roads and motorways, has already constructed green bridges over the A556 near Chester and the A21 at Scotney Castle in Sussex, while further green bridges are under construction, as part of the A417 Missing Link scheme near Gloucester, and at Cockrow in Surrey, as part of the M25 Wisley interchange scheme.

Material for the top soiling work has been sustainably generated from the scheme’s earthworks, with around 960 tonnes of soil laid across the bridge deck and embankments, while a total of 87,000 trees are being planted across the landscape, in addition to the green bridge planting.

Andrew Alcorn, National Highways’ Programme Manager for the A30 Chiverton to Carland Cross scheme, said: “We’re really proud of the environmental work we’ve invested in this project, and the creation of the green bridge is a leading part of that.

“Along with other environmental measures, we’ve built a total of 33 multi-species crossing points as part of the project, and we look forward to seeing the bridge bloom for many years to come, providing a real legacy for the scheme and for Cornwall.”

(Picture: National Highways)