Thames Tideway Tunnel

The Thames Tideway Tunnel project will improve the sewer networks across London and the Thames Valley. A new 25km long ‘super sewer’ will run from Acton to the Abbey Mills Pumping Station in Stratford, with the majority of the tunnel running under the river. It will collect the sewage and rainwater that currently pollutes the Thames and treat it before returning it to the river.

Thames_Tideway_Super_Sewer Thames_Tideway_£4.2_Billion_Cost New_Public_Space_Along_River_Thames


£4.2 billion

3 acres

super sewer which will protect the river  estimated project cost of new public space along the river

The project is estimated to cost £4.2 billion. Preparatory work began in 2015, and by 2020 construction was underway at all 24 sites in London. The majority of the engineering work is being carried out by Tideway, a separate company independent of Thames Water, who will finish construction by 2024 and hand over the tunnel for Thames Water to operate.

Over five years, Tideway will transform the sewer systems in the UK’s capital. Originally built in the 1860’s, the network was designed for a population of four million. Today London has a population of approximately nine million people. This dramatic expansion of London and its population has put pressure on the system, which is struggling to keep up the demand upon it.

This project will upgrade the sewer system, future-proofing it for generations to come. The primary aim of the project is to prevent the overflowing of the ‘combined sewer overflow' (CSO) along the Thames. Following heavy rainfall, CSOs pollute the Thames, breaching the EU Urban Waste Water Directive.

The Tideway Tunnel will intercept sewage before it overflows through CSO discharge points, which will be connected to the tunnel under the Thames. Instead of flowing into the river, the dirty water will be stored in the super sewer. It will then be treated and the clean water will be released into the river.




Asite’s cloud-based platform will provide a tool for communication and collaboration between all project stakeholders, allowing them to organize the project successfully. This becomes vitally important when schedules are tight, and there are small challenging project sites.

The Common Data Environment (CDE) provided by Asite allows online secure collaboration, which will streamline every process, helping to drive down project costs and risk, and increase collaboration across the entire project supply chain.

During the project and upon completion, the Thames Tideway Tunnel will improve the environment, ecology, public health, appearance, reputation, and long-term economy of London. It will also give a much-needed and immediate boost to the economy by offering many thousands of skilled jobs and hundreds of apprenticeships.

The Thames Tideway Tunnel is the biggest infrastructure project ever undertaken by the UK water industry. The project includes 24 construction sites, 11 of which are located along the banks of the Thames, 12 design disciplines, and numerous supply chain companies. The project is anticipated to be completed in 2024. The Tideway project promotes innovation in their work and aims to push the boundaries to deliver value, right-first-time quality, and sustainability.

When completed, it will improve London’s sewer system and also introduce three acres of new public space along the route of the River Thames at seven different locations.

With the help of Asite, the Thames Tideway Tunnel will meet the current and future needs of Thames Water customers and serve their needs for generations to come.





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