The hefty upgrade work on Bank station is set to be completed later than planned, and over budget, according to new papers from Transport for London (TfL).
TfL said in its recent investment programme report that final costs for the revamp at Bank are set to be £642m, £19m higher than the £623m originally forecast. That covers a capacity boost and systems integration upgrade at the station.
Overall works were originally expected to be completed in late 2021, but this has now been put back to 2022.
The main contractor recently submitted a cost forecast that puts the original predicted total "under pressure".
TfL said the forecasts were now under review, but added that there should be opportunities to mitigate the pressure on cost.
So far, £322m has been spent on the overall Bank station capacity and systems integration and upgrade.
TfL is increasing capacity at the City hub and providing a speedier interchange for customers, including a new Northern Line southbound tunnel, as well as a new entrance at Cannon Street. When works are finished, Bank station's capacity should be improved by 40 per cent.
A new Bank station entrance for the Waterloo & City Line is also being built.
Progress on the works
On the plus side, the transport body said tunnelling works to create the new Northern Line tunnel were "well under way", and the initial works for the new ticket hall are complete.
On the negative side, issues obtaining fire doors with the correct certification has thrown a spanner in the works for the new Waterloo & City Line entrance, so that is now expected to open in March rather than January next year.
TfL said it was reviewing the schedule though, to see if that can be brought forward.
Stuart Harvey, TfL's director of major projects, said:
We are undertaking a huge modernisation of Bank Tube station to reduce congestion and make journeys quicker and easier for the near half a million customers who use the station every day.
Building 600 metres of brand new tunnels deep underground is challenging and we have discovered unforseen obstructions that have made the process even more complex. We are working collaboratively with our contractor to develop plans to help us deliver these essential improvements for customers and businesses on time and to budget.
Reasons for the upgrade
Between them, Bank and Monument stations are served by five Underground lines as well as the DLR. During the morning peak period, around 123,000 passengers use Bank each day.
The station is remaining open to customers throughout the upgrade to the station, and most of the construction is taking place below ground to minimise disruption. Part of the Northern Line branch will be closed in 2020 though, to connect new sections of tunnel safely.
Closures are expected to be from April to May in 2020, with the line closed in both directions Moorgate to Kennington, and from May to August that year, with northbound trains not stopping at Bank and the southbound line closed Moorgate to Kennington.