VINCI Construction Grands Projets and Bachy Soletanche Ltd (VINCI subsidiaries), in a joint venture with Costain, have signed the contract for the East works package of the Thames Tideway Tunnel with Bazalgette Tunnel Limited, the consortium of investors that holds the concession for the project. The contract is worth €858 million (£605 million).
The works package includes the construction of two sections of tunnel, a main tunnel (5.5 km) and a connecting tunnel (4.6 km) for combined rainwater and wastewater to the east of London. Located between 45 and 65 metres below ground, the two tunnels will be excavated using slurry pressure balance tunnel boring machines. The main tunnel will have an interior diameter of 7.20 metres, while that of the connecting tunnel will be 5 metres. The East section also includes the construction of five large shafts (diameters of between 17 and 25 metres), maritime works on the Thames, structures connecting with the existing wastewater collection system and electromechanical works packages.
A project optimisation phase (design, methods, etc.) is starting immediately. The launch of works on the site is planned for 2016, with delivery scheduled for 2024.
The East works package is one of three making up the Thames Tideway Tunnel, a programme that calls for the construction of a total of 25 km of tunnels. The Thames Tideway Tunnel is needed to tackle the issue of discharges of untreated sewage into the river and ensure that London’s sewerage system is fit for the 21st century.
This contract follows on from that for the Lee Tunnel, which VINCI Construction Grands Projets and Bachy Soletanche started building to the east of London in January 2010.
Source and Link: The EPC Engineer