More than a million trees will be planted as part of a new road tunnel scheme under the River Thames, Government roads agency National Highways has said.
A community woodland and two public parks are among the 400 hectares (1,000 acres) of “landscape-scale” forest creation planned as part of the proposed Lower Thames Crossing.
Plans include planting more than one million extra trees in Kent and in Thurrock, Havering and Brentwood in Essex to help the project address its impact on the environment.
National Highways said the Lower Thames Crossing aims to be the greenest road ever built in the UK, but campaigners at the Woodland Trust have criticised its impact on “irreplaceable” ancient woodland, wildlife and increased carbon emissions.
The project aims to almost double road capacity across the Thames east of London and ease congestion on the Dartford Crossing, and National Highways said the new route would connect residents to jobs, boost the economy and create new public parks and woodland habitat.
The “landscape scale” proposals would include public parks in Thurrock and Gravesham, a new community woodland in Brentwood, and other areas of native broadleaf trees and habitat creation, including grassland, hedgerows and ponds, from Maidstone in Kent to Upminster in the London Borough Havering.
The area of ancient woodland lost by construction of the new road has been reduced to less than 12 hectares, National Highways said.
While the roads agency acknowledges that the ancient woodland is irreplaceable, it says its strategy will provide six times as much woodland as that lost.
Matt Palmer, executive director for the Lower Thames Crossing, said: “The Lower Thames Crossing will tackle the daily frustration caused by the congestion at Dartford, improve journeys and bring exciting opportunities for new jobs and businesses across the region, but we are determined that this will not come at the expense of the environment.
“We have planned its route and how we build it to not only reduce its impact but leave a legacy of bigger, better-connected and well-managed habitats that would give local wildlife and plant life the chance to thrive long into the future.”
But Jack Taylor, lead campaigner, Woodland Trust, said: “No number of new trees compensates for the loss of irreplaceable ancient woodland; centuries old and nature’s own carbon stores.”
He also criticised National Highways (NH) for saying it could transfer soil from cleared ancient woodland as part of efforts to create new habitat as “touting a flawed concept”.
And he said: “While we know it will be one of the highest emitting roads currently planned in the UK, NH still haven’t come clean on the full impacts of the project on nature.
“They are quick to talk about what they’ll plant and create, but very resistant to disclose what will be destroyed in the first place.
“We’re fighting both a nature and climate crisis, and destruction like this for a road scheme beggars belief,” he said.