The Thames Tideway project has been delayed by nine months and an additional £233m has been added to the project costs.
In an update to investors, trading company Bazalgette Finance said its latest modelling indicates that construction work is now likely to be completed in the first half of 2025, and costs are forecasted to hit £4.1bn.
The project’s annual report, published in June, stated that Thames Tideway’s cost estimate had risen to £3.9bn and handover had been pushed back three months to June 2024.
The impact of the coronavirus pandemic on operations has been cited as the cause of the latest delay.
Tunnelling restarted on the project, which will run from Stratford in east London to Action in the west of the city, in May, after all but essential work was halted in March.
The 25km ‘super sewer’ is being constructed by a Bam, Balfour Beatty and Morgan Sindall joint venture.
A large tunnel boring machine, which is to be used to create the final 5.5km stretch of tunnel, arrived in central London by boat last month.
