The next phase of procurement for the main construction works contracts for the Thames Tideway Tunnel has been reached as the invitation to tender was sent out for the second works package - worth between £500m to £800m.

Thames Water sent out the Invitation to Tender (ITT) for the East package of work to construct the 25 kilometre tunnel in London yesterday, with the final bidders expected to be announced in May 2015.

The project has been split geographically into three main construction works contracts, with the ITT for West sent out in December, and the final Central section expected to be released in April 2014.

The Development Consent Application for the Tunnel is currently being considered by the Planning Inspectorate and, subject to consent being granted, construction on the project is due to start in 2016 and will involve 24 construction sites across London.

The three main works packages are worth a total of up to £2.3 billion – West (£300m – £500m), Central (£600m – £950m) and East (£500m – £800m). The procurement process for the West section began in December.

Mike Gerrard, Thames Tideway Tunnel managing director, said:

“The tender process is now well under way and we are confident that our process will ensure 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.”

Work on the tunnel is expected to create more than 9,000 jobs – Thames Water said around 500 people are already working on the project.

The project is expected to be financed and delivered by an independent Infrastructure Provider (IP), with its own licence from Ofwat. Thames Water, Government and Ofwat are continuing to work together to finalise the financing arrangements for the project. Procurement of the new IP is expected to begin later this year.

Shortlisted bidders for each of the construction packages are as follows:

West

• Bam Nuttall, Balfour Beatty, Morgan Sindall JV
• Costain, Vinci, Bachy JV
• Dragados, Samsung JV
• Ferrovial Agroman, Laing O’Rourke JV

Central

• Bam Nuttall, Balfour Beatty, Morgan Sindall JV
• Costain, Vinci, Bachy JV
• Ferrovial Agroman, Laing O’Rourke JV
• Skanska, Bilfinger, Razel Bec JV

East

• Bam Nuttall, Balfour Beatty, Morgan Sindall JV
• Bechtel, Strabag JV
• Bouygues Travaux Publics
• Costain, Vinci, Bachy JV
• Hochtief, Murphy JV

Final preferred bidders are expected to be announced in early 2015.