The installation of 12 precast concrete beams will be the initial stage of forming the deck of the new overbridge.

When this reaches completion, it will maintain access for local residents, businesses and landowners across the future dual carriageway.

Using a specialist crane, the beams measuring up to 33.5 metres in length and weighing up to 84 tonnes will be put in place during overnight works.

Ruth Whillis, Transport Scotland project manager, said: “The installation of the Guay Overbridge beams is an important step forward for the Tay Crossing to Ballinluig project and a visible sign of construction progress.

“Planning this major milestone has taken months of preparation and teamwork between designers, engineers, contractors and stakeholders.”

Whillis added: “The beam installation is a complex engineering operation requiring detailed planning, specialist equipment and close coordination.”

Overnight closures of the A9 will be required between the Tay Crossing and Kindallachan from 30 November until the morning of 5 December, between 9pm and 5am every night, so that the lifts can be carried out safely.

Road users will be able to go through the works during amnesty periods between 11pm and midnight and between 2am and 3am, when lifting operations will draw to a halt. 

Closure of the A9 is needed because beams need to be positioned over and adjacent to the live carriageway. Access for emergency services will be maintained at all times of the works.

John Stephens, Wills Bros Contractor’s representative, said: “This is one of the most complex lifting operations undertaken on the project to date.

“A full road closure is required because it is not possible to safely lift and position beams of this size above live traffic.

“The works have been carefully planned and scheduled overnight, when traffic volumes are lower, to help minimise disruption.”

Stephens added: “The amnesty periods will provide opportunities for traffic to pass through the works area while enabling the beam installation to be completed efficiently and safely.”