Thames Water has sent out the invitation to tender (ITT) for the Central package of work to construct the 25km tunnel in London, with the successful bidders expected to be announced in May 2015.
The project has been split geographically into three main construction contracts, with the ITT for West sent out in December 2013 and East in January 2014.
The three main works packages are worth a total of up to £2.3bn: West is estimated at £300m to £500m; Central at £600m to £950m; and East at £500m to £800m.
The Thames Tideway Tunnel is a major new sewer that will help tackle the problem of overflows from the capital’s Victorian sewers and will protect the tidal River Thames from increasing pollution for at least the next 100 years.
The development consent application is currently being considered by the Planning Inspectorate. Subject to consent being granted, construction on the project is due to start in 2016 and will involve 24 construction sites across London.
Thames Tideway Tunnel managing director Mike Gerrard said: “We are making excellent progress with the tender process and we are confident that we will receive competitive bids that will result in the best value for our customers.
“We are building for 22nd Century London to create a cleaner, healthier River Thames. The Thames Tideway Tunnel is needed to tackle the tens of millions of tonnes of raw sewage which discharge into the tidal River Thames every year. The river needs cleaning up and it needs to be cleaned up now.”
Alongside the environmental improvements to the tidal River Thames, the tunnel will create more than 9,000 jobs. Already, around 500 people are working on the project.
The project will be financed and delivered by an independent infrastructure provider (IP), with its own licence from Ofwat. Procurement of the new IP is expected to begin next month.