Tideway strives to complete super sewer two years early

Tideway aims to reduce the delivery timetable for its £4.2 billion super sewer, due for completion in 2023, by up to two years.

The firm’s chief executive Andy Mitchell said this would require a “radical change” to the timetable for the Thames Tideway Tunnel, with work on the site to start six months early, tunnelling to start a year early and another year shaved off commissioning.

“We’re not talking about cutting corners, or rushing the job” he said. “But we believe we can start earlier than planned, and we can overlap more by bringing in more resources.

“It is a radical change in the programme, but if you have that radical ambition like we do, there is only one time to call it – and that is now.”

Preliminary construction is due to begin next year, with tunnelling due to start in 2017 and end in 2021, commisioning in 2022, and all works to be completed by 2023.

Tideway started its first major piece of work at Blackfriars earlier this month, having started work on a new pier to allow continued use of river transport during construction of the Tunnel.

Every year, tens of millions of tonnes of sewage overflows into the River Thames from combined sewage overflow (CSO) points along the river.

The Thames Tideway Tunnel will intercept sewage from the 34 most polluting CSOs, including at Blackfriars, before transferring it to Thames Water’s Beckton Sewage Treatment Works.

During construction Tideway is aiming to transport 90 per cent of spoil from the main tunnel by river, drastically cutting down on the number of lorry trips that would otherwise be needed.