HS2 to create 127-hectare biodiversity hotspot to assist carbon reduction efforts
The HS2 project team has announced plans to create more than 120 hectares of new carbon-sequestering grassland, woodland and wetland habitats that will reuse soil and chalk from tunnel excavations.
Last February, Boris Johnson approved the HS2 project, aimed at radically reducing journey times between London and the north of England. The decision has angered MPs, especially those located in areas where construction of the project is likely to destroy natural locations. The fact that the cost of HS2 has ballooned to more than £100bn has also created more detractors.
One of the key criticism of the project is the impact it is expected to have on natural habitats and the emissions associated with the project.
The Government remains adamant that HS2 will be in alignment with national climate goals, and the project’s landscape architects, ecologists, engineers and soil specialists have drawn up plans to create 127 hectares of new biodiversity hotspots.
The Colne Valley Western Slopes project will consist of 127 hectares of new chalk grassland, woodland, wood pasture and wetland habitats to improve the local environment. It will neighbour the Chilterns Area of Outstanding Natural Beauty.
Around 65,000 trees and 32 species of shrubs will be planted along with 3.5km of hedgerows. In addition, around 90 hectares of calcareous grasslands that support a rich variety of flora and has been highlighted by Natural England as being robust to the impacts of climate change, will be created.
The project will reuse existing soil and will recycle three million m3 of chalk from tunnel excavation, as well as concrete and limestone aggregate used in the construction process.
HS2’s environment director Peter Miller said: “This project forms a major part of HS2’s Green Corridor programme to establish better connected, sustainable and biodiverse landscapes along the route of the new railway that will contribute substantially to HS2’s carbon reduction target.
“It demonstrates HS2’s approach to addressing many of the complex issues surrounding climate change and which are central to protecting our environment, and is a great example of how good design and planning can mitigate the effects of climate change.”
HS2 claims that the project will assist with wider carbon reduction targets by delivering ecological gain and sequestering carbon. The project is yet to provide estimates on how much carbon could be sequestered. Additional carbon reductions will be achieved by reducing road haulage and waste treatment activities.
However, the project follows a history of initiatives from HS2 that have received major backlash from green campaigners.
HS2 was proposed when the UK was still performing towards the aims of the 2008 Climate Change Act. But the Conservatives have since enshrined a net-zero emissions target into law, and there are serious concerns as to whether the HS2 project can comply with this vision.
By the Government's own admission, greenhouse gas emissions associated with the construction of HS2 "are significant". The carbon associated with construction is estimated to range between 5.7 million and 6.1 million tonnes. The residual carbon ranges between 2.5 million tCO2e and 3,1million tCO2e. "This includes all emissions associated with construction, operation and maintenance of the Proposed Scheme, as well as modal shift, carbon mitigation from tree planting and freight benefits from released capacity on the classic network", the Government notes.
The HS2 Environmental Policy, states a commitment to “developing an exemplar project, and to limiting negative impacts through design, mitigation and by challenging industry standards whilst seeking environmental enhancements”.
As part of this commitment, HS2 had made a pledge to ensuring no net loss of biodiversity at a route-wide level. This falls just short of the Government’s 25 Year Environment Plan to embed net-gains for the environment into infrastructure projects.
The Wildlife Trusts’ own examination of HS2 has outlined the stark ecological damage that the project will cause.
Claiming that HS2’s own assertations that no net loss of biodiversity will be achieved are “based on out-of-date and incomplete Local Wildlife Site data”, the report warns that almost 700 classified local wildlife sites are at risk due to the project.
Other notable sites at risk include five wildlife refuges of international importance, protected by UK law; 33 sites of Special Scientific Interest which are protected by UK law and four nature improvement areas that have been backed by £1.7m in Defra funds. In addition, 18 Wildlife Trust Nature Reserves and 108 ancient woodlands are at risk.
The report warns that HS2 is focusing on “inappropriate mitigation”, such as tree planting on habitats that would suffer as a result, like species-rich grassland and wetland habitats. Instead of creating a “green corridor”, HS2 “may actually destroy important existing habitats”, the report notes.
The HS2 - towards a zero-carbon future report recommends tree planting to take place as soon as possible to help with the offsetting of both carbon emissions and wildlife destruction.
The project had earmarked seven million trees to replace woodland that would be cut down to make way for the 216km London to Birmingham line. However, HS2 confirmed to the Leamington Observer that nearly 90,000 of the 240,000 trees planted, needed to be replaced.