Super sewer set for Thames
BY TOBY PORTER
toby@slpmedia.co.uk
Tunnelling is set to begin later this year on a super sewer below the Thames, which will ensure the river does not have to be full of waste in wet weather
When London’s drainage overflows in heavy rain, the excess waste is diverted into the waterway to take it out to the sea. But from 2023, the over matter will be channelled down the 25km-long 7.2m-wide Thames Tideway Tunnel, which is to be constructed under the river.

Once completed, it will stop millions of tonnes of untreated sewage flowing into the Thames each year.
The project recently completed a key milestone, with the excavation of its first Tunnel Boring Machine (TBM) launch shaft. At 60m deep, 45,000 cubic metres of spoil was excavated to create the shaft – enough to fill 18 Olympic-sized swimming pools. The spoil was removed by barge along the river.
The shaft measures 31m in diameter, equivalent to the dome of St Paul’s Cathedral.
Tideway, the company delivering the new super sewer, has this week launched an app that allows people to explore what is going on underneath the city as the tunnel is being built.
The app has been designed to provide teachers, students and anyone interested in the project with an interactive way of learning about it. Features include an interactive map of Tideway’s construction sites, a 3D model of a giant Tunnel Boring Machine and profiles of career options on the project.
One particularly exciting feature is the ability to watch the tunnel being built in 3D, gaining a full understanding of how the machines work.
The app is now live at https://www.tideway.london/tunnelworks/