Tideway, the company building London’s new super sewer, has published its latest annual report and accounts, detailing a year in which almost all underground works were completed.
The company is now preparing to commission the new infrastructure in 2024, when it will start protecting the River Thames from sewage pollution for the first time. The system is due to be fully operational in 2025 when an estimated 95 per cent of sewage overflows will be prevented from spilling into the tidal Thames.
Tideway’s report confirms that the capital cost of the project remains £4.5bn, as reported in April, 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.
Several milestones were achieved during the year including completion of primary tunnelling works; completion of secondary lining of the west and central sections of the tunnel; and completion of shaft cover slabs at five sites. The removal of temporary river structures began in earnest and worksite system acceptance tests were carried out at three sites in preparation for system commissioning.
Tideway CEO Andy Mitchell said: “Awareness of the health of our waterways and our environment has never been higher than it is today, and so I am pleased to report that London is closer than ever to a cleaner, healthier River Thames.
“We’ve worked for eight years deep underground, but it’s wonderful to see our works beginning to take shape on the surface.
“Next year is all about switching the system on and diverting pollution away from the Thames for the first time – this is what we’re focussed on, and we’re all looking forward to a healthier future for London.”
Significant work was undertaken above ground during the year. Permanent riverside structures became visible on many sites, including bronze ventilation columns, the first artworks forming part of Tideway’s extensive art programme and ‘floodable’, intertidal terracing at Chelsea and Victoria Embankments which will encourage a range of habitats.
The first new riverside public space to be created by the project is due to open later in 2023, at Putney in Wandsworth.
Tideway Chair Sir Neville Simms said: “The past 12 months on the Tideway project have seen the most significant change in focus since we started work – with the construction phase nearing completion and attention turning to testing this new and vital infrastructure.
“As we look forward to bringing the system on-line next year, our delivery model – which encourages long-term private investment in infrastructure – is showing its worth in delivering value for all stakeholders.
“In reporting our progress this year, I pay tribute to our teams, partners and stakeholders in supporting our efforts to get this vital, nationally significant project over the line.”
Tideway also today published its latest Sustainability Report, which details the progress and impact of the project’s legacy programme.
The Sustainability Report includes Tideway’s response to the Task Force on Climate-Related Financial Disclosures (TCFD) as well as analysis from Tideway’s first social impact analysis to quantify the social value of the project beyond legally binding baseline targets.
Ratings agency S&P increased its ESG evaluation of the company during the year to a score of 77 reflecting the focus on sustainability and strong corporate governance.