HS2 confirms Chilterns tunnel extension

Hybrid Bill amendment will allow for 2.6km extension to Buckinghamshire tunnel on environment grounds.

People living in and around South Heath, Hyde Heath and Great Missenden in Buckinghamshire have won the battle for an extension to the Chilterns tunnel proposed as part of the HS2 rail project.

Following detailed engineering and environmental assessment, the Government has  agreed to propose an amendment to the HS2 hybrid Bill to extend the deep-bored Chilterns tunnel 2.6km to a new portal just past South Heath.

"By continuing the main tunnel all the way past the village, a separate ‘green tunnel’, designed to reduce noise and help blend the line into the landscape, would no longer be needed," HS2 said.

As well as reducing the scale and duration of local construction activity, the new proposals would also preserve 12 hectares of woodland at the nearby Mantle’s Wood, Sibley’s Coppice and Farthings Wood, it said.

The changes are in line with the recommendations of the Hybrid Bill Select Committee, the group of MPs tasked with considering petitions against the Bill. The new proposals will be included in a future Additional Provision to the Bill.

"We are committed to listening to the communities that live along the HS2 route as we deliver the railway’s important national benefits. These new proposals will protect woodland and mean less disruption for people living nearby. It is essential that we take their views into account so that we build this vital railway in the best way possible," said transport minister Robert Goodwill.

The decision to extend the tunnel is evidence that HS2 is taking note of local community concerns, HS2 Ltd said.

"HS2 is determined to keep the environmental impact of the project as small as possible and we recognise the importance of listening to stakeholders and local communities as we continue to develop the scheme," said HS2 managing director of development Alison Munro.

"Major infrastructure projects like HS2 will always be about striking a balance between engineering, cost and environmental impacts. We will remain open to potential design improvements and I believe today’s proposals would deliver a successful long-term solution for South Heath, Hyde Heath, Great Missenden and the wider area." 

The HS2 select committe directed the working up of an additional provision to the HS2 hybrid bill for a 2.6km northward extension of the Chilterns deep-bored tunnel near South Heath in July.

"The Committee stipulated a review of the effects of that extension and will want to see that the additional deepening of the cutting at the tunnel exit will have adequate beneficial effects," it said. 

Following the news that Department for Transport and HS2 had taken up it suggestion for the extension the committe said that when considering whether other, further mitigation options are merited, it will " need to be satisfied that there are adequate beneficial effects in the South Heath area. Pending that, petitioners from the Chilterns appearing before the Committee in September and October should make their representations on the basis that the proposed extension replaces the Bill scheme as the current design. Anyone adversely affected by the proposal will be able to petition against it when it is formally deposited."

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