Contractor taps into €465m renovation of major London water treatment plant

The Spanish infrastructure giant Acciona has secured a prestigious €465 million contract to completely overhaul one of London’s most critical water infrastructure assets. The Coppermills Water Treatment Plant, responsible for supplying approximately one-third of Greater London’s drinking water, will undergo extensive modernization to ensure continued reliable service for millions of residents across the capital. This landmark project represents a significant investment in aging UK infrastructure and highlights the growing focus on sustainable water management in urban environments.

A Vital Water Source for London

Located in the Lea Valley, the Coppermills Water Treatment Works has been an integral part of London’s water supply network since 1969. The facility currently serves 32 boroughs of Greater London as well as the City of London, making it a cornerstone of the capital’s water infrastructure. After six decades of continuous operation, the plant now requires comprehensive modernization to meet both current demands and future challenges.

Thames Water, the private utility responsible for water services across much of the British capital, has committed £400 million (approximately €465 million) to enhance the plant’s reliability over the next seven years. This investment comes as part of the company’s broader strategy to improve infrastructure resilience and service quality throughout its network.

Scope of Renovation Works

The renovation project encompasses several major components designed to significantly improve the facility’s operational capabilities. Acciona will handle the complete design, construction, and commissioning of the upgraded infrastructure before transferring the plant back to Thames Water upon completion.

Key elements of the planned improvements include constructing a new pumping station to replace the aging 1960s installation, implementing advanced filtration and treatment systems to enhance water quality, and upgrading the plant’s electrical infrastructure to support modern equipment needs.

John Bentley, Thames Water’s capital delivery director, emphasized the strategic importance of such infrastructure investments: “This project will help to improve the quality of water supply, as well as making sure the site is ready to handle the expected increase in London’s population in the future.”

Engineering firm Jacobs will serve as the lead designer on the project, bringing their expertise in large-scale water infrastructure to bear on this complex renovation effort.

Meeting Regulatory Requirements

The renovation will align Coppermills with the latest regulatory standards set by Ofwat, the UK water industry regulator. New pipes, chambers, and control structures will be constructed above and below ground to enhance system resilience and ensure rapid recovery capabilities during any potential water quality incidents.

Additionally, as the facility is situated near the Lee Valley Special Protection Area, a habitat assessment will be conducted to ensure the construction work does not negatively impact the diverse bird species that inhabit this ecologically sensitive region.

Acciona’s Growing UK Footprint

This contract represents another significant milestone in Acciona’s expanding UK operations. The Spanish infrastructure group has been active in the United Kingdom since 2003 and has steadily built a portfolio of major projects across the country.

In early 2022, Acciona secured a turnkey contract with the North London Waste Authority to develop the Edmonton EcoPark waste-to-energy facility. This impressive installation will process 700,000 tonnes of waste annually while providing power and heat to 50,000 homes. Prior to that, in 2019, the company won the contract to build and operate the NESS Energy Project in Aberdeen, Scotland, a facility with a treatment capacity of 150,000 tonnes per year.

José Manuel Entrecanales, Acciona’s Chairman and CEO, has previously expressed strong confidence in the UK market, noting: “We find that the UK has, by far, the best variables for growth and stability. It is a legally binding country, which is a show of legal maturity because people need the resources of law and legal arbitration because it is very efficient.”

Project Timeline and Community Engagement

The project timeline spans several years, with planning applications for the pumping station building expected to be submitted in Spring/Summer 2025. Subject to approvals, on-site construction work is scheduled to begin in Spring/Summer 2026, with final completion targeted for Spring/Summer 2032.

Thames Water has already initiated community engagement efforts, holding the first public drop-in session on January 29, 2025, to introduce local residents to the planned works and address any concerns. All construction activities will take place within the existing site boundaries, with no expansion of the external perimeter planned.

Final Thoughts

This major investment comes at a critical time for London’s water infrastructure. According to Thames Water’s 2023/24 Annual Report, the company is facing significant challenges with its aging network, parts of which are up to 150 years old. The report notes: “We deliver 2.5 billion litres of safe drinking water to 10 million customers and treat 5.1 billion litres of wastewater for 16 million customers every single day. And our service is provided over an extensive infrastructure that is underinvested in and tired.”

The Coppermills renovation forms part of Thames Water’s broader £19.8 billion expenditure plan, with increased focus on environmental projects and infrastructure reliability. The company reported a 21% year-on-year increase in underlying EBITDA to £1.2 billion in FY24, providing financial capacity for these essential infrastructure investments.