HS2 has revealed the final design for the Chalfont St Peter vent shaft headhouse – the first of four structures that will be built to provide ventilation and emergency access to the high-speed rail line’s 10 mile-long Chiltern tunnel.

Taking its inspiration from the style of local barns and other agricultural buildings, HS2 says the headhouse is designed to fit into the surrounding landscape.

Below ground level, a 60 metre ventilation shaft will reach down to the twin tunnels below, with fans and other equipment designed to regulate air quality and temperature in the tunnels, remove smoke in the event of a fire and provide access for the emergency services.

HS2 engaged with the Chilterns AONB Review Group during the development of the designs and held a series of public engagement events to gather views from the local community.

They came up with single-storey buildings with zinc roofs and dark bronze doors and vent openings.

HS2 says mature trees along the existing boundary are being kept "as far as possible" and when the site is complete, new trees and hedgerows will be planted.

To encourage wildlife to return, bird boxes, reptile basking banks, a grass snake laying heap and a hibernaculum will also be created.

Material excavated from the shaft will be used to create much of the landscaping in a bid to avoid putting extra lorries onto local roads.

The plans have been drawn up by HS2 Ltd’s main works contractor Align JV – a team made up of Bouygues Travaux Publics, Sir Robert McAlpine, and VolkerFitzpatrick - working with its design partners Jacobs and Ingerop-Rendel, and the architect Grimshaw and landscape designers, LDA.

Diane Metcalfe, Associate Principal at Grimshaw, said: “Chalfont St Peter Ventilation Shaft has been sensitively designed to complement the rural character of the Chilterns.

"The position and orientation of the headhouse buildings are located to conceal them within the landscape and form a courtyard similar to local farmyard arrangements.

“The pitched roof, zinc-clad buildings are a modern interpretation of the local agricultural and industrial vernacular.

"Design proposals are a result of close and collaborative engagement with the AONB Review Group.”

A temporary access road is set to be completed soon to link the site with the A413 Amersham Road, which will allow construction traffic to avoid the centre of Chalfont St Peter and stop HGVs driving past Robertswood School and the Epilepsy Society.

A new temporary marshalled lorry holding area will also be put in place on the A413 near Gerrards Cross.

HGVs can be held in this layby until their approach to the vent shaft site is clear – helping to reduce congestion and eliminate queueing at the site entrance.

The plans for the headhouse have now gone on public display, with residents invited to attend a month-long virtual engagement event where they will be able to learn more about the design and construction of the vent shaft and headhouse.

Go to www.hs2inbucksandox.co.uk.