HS2 has welcomed the sign off for the designs for its 'cut and cover' tunnel at Burton Green.

The plans for the southern end of the structure had already been approved by Warwick District Council, where the railway will travel in a 400-metre green tunnel.

And now Solihull Metropolitan Borough Council has approved the plans for the northern section of the structure, where the railway exits the tunnel in a 1.4 kilometre cutting with retained walls.

A key feature for this area is the realignment of the Kenilworth Greenway, which will cross under Cromwell Lane and then cross the roof of the green tunnel and run alongside the railway cutting.

HS2 said large-scale planting of native trees and shrubs will provide biodiverse habitats for wildlife, shield the greenway visibly from the new railway, and re-establish vegetated connections to Black Waste Wood and Little Poors Wood.

Alan Payne, HS2's senior project manager said: "We're delighted to receive Schedule 17 planning consent for the northern section of the green tunnel from Solihull Council.

"We're committed to maximising green space around the new high speed railway, and have worked with residents and authorities to ensure our tunnel design conserves, enhances and transforms the landscape in this area.

"The design for the permanent realignment for the Kenilworth Greenway and the landscape infrastructure created over the green tunnel is central to how we deliver this, linking the local community and railway with the wider landscape."

The southern portal for Burton Green tunnel (image via HS2)

The green tunnel in Burton Green was designed by the Mott MacDonald SYSTRA Design Joint Venture working for HS2's main works contractor for the West Midlands, Balfour Beatty VINCI (BBV), who are constructing 90km of HS2 between Long Itchington in Warwickshire to the centre of Birmingham and on to Staffordshire.

Construction of the underground elements of the tunnel has already started, including the widening of the old historic railway cutting to the width of the new tunnel, construction of the wall panels to the north of Cromwell Lane, and completion of the diversion of Cromwell Lane to facilitate the start of construction of the tunnel's southern section.

The south portal and tunnel wall panels have been built, along with the solid tunnel roof to the north of the original Cromwell Lane bridge, and work is progressing on the Cromwell Lane underpass to allow for the diversion of Cromwell Lane.

Over the coming months, the main tunnel will continue to be excavated, the old Cromwell Lane bridge will be demolished and work will start on the roof slab to the south of Cromwell Lane.

A CGI impression of Waste Lane overbridge, with the greenway alongside the new railway line (image via HS2)

Once the tunnel is built, the cutting will be back filled with soils as the basis for recreating the landscape, and soil will conceal the tunnel roof to support new native woodland planting, reconnected wildlife corridors and new public footpaths.

New ecological features such as wildflower species found locally, and bat and bird boxes will create bigger and better wildlife habitats.

While the railway is being built, HS2 has created a temporary route for the Kenilworth Greenway which starts at the site of the new Burton Green Village Hall and then follows the existing field boundaries linking with Berkswell Station.