Design woes and complications following Carillion’s collapse has pushed back the procurement process for the £263M Barking Riverside extension by a total of seven months, Transport for London (TfL) has revealed.
In December New Civil Engineer reported that design complications on the east London rail scheme had delayed an invitation to tender (ITT) by five months, to February 2018.
Carillion had been one of the bidders for the 4km extension and removing the liquidated firm from the procurement process added to a delay in issuing the ITT, which was released quietly on 13 April.
Transport secretary Chris Grayling had granted a Transport and Works Act Order (TWAO) in August last year.
“The Secretary of State approved our TWAO application in August 2017, the necessary funding and other agreements are in place and the demolition stages of the early works have been completed on time,” said TfL in board papers.
“However, completion of the detailed design and having to remove Carillion plc (one of the pre-qualified bidders) from the process, once they entered into compulsory liquidation, caused the release of the Invitation to Tender (ITT) for the contract for the construction of the extension and station (Main Works Contract) to be delayed by seven months.”
Balfour Beatty and Volker Fitzpatrick are still in the running for construction of the extension project, which will involve 1.6km of new track. A contract award is expected in late summer.
Complications around traction power and topographical surveys were blamed for the design delay. After the scheme was given the green light, detailed site investigations across the proposed route uncovered pockets of poor ground conditions that would make it difficult to support the rail track.
A decision to switch power provision for the line from a substation in Barking to a larger station in West Ham with more capacity required extra assessment work, further delaying completion of the design phase, carried out by Arcadis.
The Barking Riverside extension will add 4km to the London Overground Gospel Oak to Barking line and add a new station at Barking Riverside.
A spokesperson for TfL said the extension is anticipated to unlock development potential for 10,800 homes in the area.
He added: “While there have been some minor delays with earlier stages of the programme, actions have been taken to mitigate these and keep the end date of the project on track. Construction of the link will begin later this year and train services will still start in 2021 as planned.”
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