The Thames Tideway Tunnel is a major new sewer that will help tackle the problem of overflows and protect the River Thames from increasing pollution for at least the next 100 years.

The construction of the £4.2 billion tunnel is planned to begin in 2016 and will take seven years. It will have a diameter of 7.2 metres, broadly follow the River Thames for 25km and lie up to 70 metres below ground. This will make it the deepest and longest tunnel ever constructed in London.

For the tunnel to be completed on time, construction work is set to take place at 24 preferred sites across the capital. This is expected to generate approximately 9,350 jobs at the peak of the work. This number includes 4,250 direct construction workers and a further 5,100 indirect jobs.

Did you know...

TBC metres

The Thames Tideway Tunnel will be the same width as an average UK single-carriageway road.

Recruiting new blood for vital roles

To help cope with this potential shortfall and boost the overall number of skilled people entering the construction industry, a series of initiatives has been proposed. For example, all Thames Tideway Tunnel contractors will be required to employ at least one apprentice for every 50 of their site employees throughout their contracts. 

In addition, Thames Tideway Tunnel Ltd, major contractors, further education organisations, training organisers and fundraising agencies such as Construction Skills will work together as a Skills Planning Group. This committee will establish the future training needs of apprentices and other new entrants into the construction industry. It will also identify how employers can work with these people so they develop the right skills and experience.

Facts and figures

The width of the tunnel will fit three London buses side by side.

Each year enough sewage is flushed into the River Thames to fill the Royal Albert Hall 450 times.

The deepest point of the tunnel will be at a depth that is the same as the height of The Shard's spire.

The tunnel will be half the length of the London Marathon.

Construction will take place 24 hours a day during the project. 

Did you know...

2.2 km

With a total length of 2.2km, Humber Bridge was the longest single-span suspension bridge in the world for 17 years after it was built.