Construction has yet to start on the £263m Barking Riverside Overground extension, but work is already months behind schedule due to design issues impeding the procurement process.
There have been troubles with the issue of the main works tender due to "design complexities", and that is now 148 days - nearly five months - behind the planned date of early October, according to Transport for London's (TfL) third quarter investment programme report.
Work is still ongoing to prepare the invitation to tender documentation once the detailed design phase is completed, though TfL says it expects to issue the main works tender at the end of the month.
"We have engaged in early contractor involvement to enhance the potential contractors' knowledge and lead to a more accurate tender submission," TfL said.
And despite the difficulties, TfL says construction of the 4.5km extension should still get underway this summer with work completed in 2021 as planned.
A TfL spokesperson said: "The extension of London Overground to Barking Riverside will unlock the development potential of the area, including 10,800 new homes, new jobs and facilities including a school and health care services for the local community.
"The design stage is almost complete, which will allow the next stage of this fully-funded project to progress. Construction of the link will begin later this year and train services will still start in 2021 as planned.”
Last August, transport secretary Chris Grayling gave the go-ahead for construction to get underway on the 4.5km extension of the Gospel Oak to Barking Line, with the development expected to lead to 10,800 new homes being built.
The extension will involve a new station in Barking Riverside, with £172m of the £263m cost of the project being met by the developers. The remainder comes from TfL's growth fund, contributing to schemes that have a direct impact on unlocking housing and employment growth.
Four new London Overground trains will be run an hour, featuring air conditioning and walk-through carriages.
Here's the proposed Barking Riverside extension:
(Click or tap for bigger version.)