The multi-billion pound ‘super sewer’ tunnel will be between 6.5m and 7.2m in diameter and run under the capital along the alignment of the river Thames from Acton in the west to Abbey Mill pumping station in the east. There it will be connected to the Lee Tunnel, which will transfer the sewage to Beckton Sewage Treatment Works.
The aim is to prevent the 39 million tonnes of untreated sewage that typically overflows into tidal stretches of the Thames each year. The new tunnel will be connected to the combined sewer overflows (CSOs) that are located along the riverbanks.
The project is divided into three main contracts: West (with an estimated value of £300m-£500m); Central (£600m-£950m); and East (£500m-£800m).
The schedule is for construction to start in May 2015 and complete in spring 2023.
Contractors have until 13 September to lodge a request to be invited to tender.
For more details of the procurement process, see our Contract Leads section.
Thames Water has produced this video outlining what it is looking for in potential contractors:
For more information about the construction process, see this video: