Tideway, the company building London’s new super sewer, has published its latest annual report and accounts, detailing a year in which substantial construction works were completed and commissioning of the new infrastructure began. 

The company also marked the completion of work at five construction sites and opened the first new piece of riverside public realm at Putney Embankment.

Protection of the River Thames will begin later this year as testing of the new system starts. The super sewer is due to be fully operational in 2025.

Tideway’s report confirms that the capital cost of the project remains £4.5bn, while the cost of the project to water bill payers remains well within the original estimate set at the beginning of the project in 2015. 

Chair Sir Neville Simms announced in April 2024 that he would be stepping down from his role in September, after nine years leading the organisation and with the construction phase now complete.

In his final foreword, Sir Neville commented on the success of the model used to finance and deliver the project and reflected on his career in UK infrastructure.

He said: “While there remains important work to be done to bring the system into full operation, what has been completed to date is testament not just to the tens of thousands of people who have contributed to the project, but to the financing model. Consideration of this model for other major infrastructure investment is a clear endorsement of its utility and success - alongside a cleaner river, this is central to Tideway’s legacy.

“The construction industry has changed immeasurably since I began my career many years ago, and it is a privilege to sign off in this, my last role, as Chair of Tideway – a project that has proved to be an exemplar in many ways, raising industry standards in health safety and wellbeing, as well as through its financing and delivery.”

Tideway CEO Andy Mitchell, said:

“The fact that the Thames and its precious ecosystem will soon be protected provides hope for the future at a time of unprecedented concern for the health of our waterways. It also demonstrates that the UK, leading an international team, can successfully deliver complex infrastructure.”

Tideway also today published its final standalone Sustainability Report, which details the impact of the project’s legacy programme with many elements having now been completed. Highlights include:

• 151 individuals completed their apprenticeship with Tideway
• A 28% reduction in the project’s carbon footprint compared with the original estimate
• 35% of Tideway’s workforce were previously workless
• 25% of Tideway’s workforce was employed from within the 14 London boroughs where construction work took place
• More than 60% of Tideway’s river workers live in Greater London, Essex or Kent