Ferrovial Secures Major Thames Water Project
Ferrovial, a global leader in infrastructure, has been awarded a significant contract to upgrade the Slough Sewage Treatment Works (STW) for Thames Water. The project, valued at approximately £80 million, will be delivered through a joint venture between Ferrovial Construction and Cadagua, combining local expertise with international experience in water and wastewater infrastructure.
This latest contract builds on Ferrovial Construction’s longstanding partnership with Thames Water, including the successful delivery of the Central Section of the Thames Tideway Tunnel. It reflects Ferrovial’s ongoing commitment to investing in resilient infrastructure that addresses the evolving needs of communities and the environment. By strengthening the UK’s water infrastructure, Ferrovial is playing a central role in ensuring sustainable water management while enhancing environmental protection.
Project Scope and Objectives
The Slough STW upgrade aims to modernize the facility to meet updated Environment Agency (EA) wastewater quality standards while improving operational efficiency. The project involves several key enhancements, including expanding treatment capacity to comply with stricter environmental permits. Among the improvements are reductions in ammonia and phosphorus levels, as well as enhanced stormwater management through improved handling of high-strength return flows.
In addition to treatment improvements, the project includes the installation of a new power supply and standby systems, ensuring increased resilience and sustainability. Once completed, the upgrades will contribute to cleaner watercourses and healthier ecosystems, supporting biodiversity and environmental quality in the region. The design phase for the project began in November 2025, with construction expected to start approximately 15 months later.
Leveraging a Strong Partnership
Ferrovial Construction and Cadagua bring complementary strengths to the Slough STW project. Ferrovial Construction has over 20 years of experience delivering complex infrastructure projects in the UK, including iconic works such as the Thames Tideway Tunnel, the Silvertown Tunnel, and the Northern Line Extension. These projects demonstrate Ferrovial’s ability to execute large-scale, technically challenging works while maintaining high standards of quality, safety, and sustainability.
Cadagua, with over 50 years of experience in Spain and decades of international water and wastewater projects, brings specialist knowledge in treatment processes, plant operations, and desalination technologies. By combining Ferrovial’s local expertise with Cadagua’s international experience, the joint venture ensures a seamless integration of design, construction, and operational efficiency.
Meeting Environmental Standards
A core component of the Slough STW upgrade is compliance with enhanced Environment Agency wastewater standards. The upgraded facility will reduce pollutants such as ammonia and phosphorus, contributing to improved water quality in surrounding rivers and streams. These improvements are essential not only for regulatory compliance but also for protecting aquatic ecosystems and promoting sustainable environmental practices.
The project also focuses on stormwater management. By improving the handling of high-strength return flows, the upgraded facility will minimize the risk of untreated water entering natural waterways during heavy rainfall events. This proactive approach aligns with the UK’s broader environmental goals and ensures that communities benefit from both improved water quality and flood resilience.
Enhancing Operational Efficiency
Beyond environmental compliance, the Slough STW upgrade will enhance operational efficiency. The project includes the implementation of modern power systems and standby facilities to maintain continuous operation during power outages or maintenance periods. This ensures that the treatment works can function reliably under a range of conditions, safeguarding water quality for the local population.
The upgraded systems will also support long-term sustainability by reducing energy consumption and optimizing treatment processes. These operational enhancements reflect a holistic approach to infrastructure investment, combining environmental responsibility with practical benefits for utility operators and communities alike.
Supporting UK Water Infrastructure
This project represents a significant step in Ferrovial’s strategy to strengthen the UK’s water infrastructure. By integrating global expertise with local delivery, Ferrovial and Cadagua are providing solutions that support both environmental and societal goals. The Slough STW upgrade will serve as a model for resilient and sustainable water management, demonstrating how strategic investments can improve service delivery while protecting the natural environment.
The project also underscores Ferrovial’s commitment to collaboration and innovation. By leveraging the joint venture model, the companies can pool resources, expertise, and technical capabilities to deliver a project that meets stringent quality, environmental, and operational standards.
Proven Track Record
Ferrovial Construction has an established record of delivering complex infrastructure projects across the UK. Key achievements include the Thames Tideway Tunnel, a landmark project designed to prevent sewage pollution in the River Thames; the Silvertown Tunnel, which provides a critical new river crossing in London; and the Northern Line Extension, which improved transport connectivity while supporting sustainable urban development.
Cadagua complements this experience with decades of expertise in water treatment and desalination. The company has successfully executed projects across multiple continents, providing innovative solutions for water and wastewater management that combine technical excellence with operational efficiency. Together, the two companies bring a comprehensive skill set to the Slough STW project, ensuring the successful delivery of a facility that meets both regulatory and community needs.
Investing in a Sustainable Future
The Slough STW project highlights Ferrovial’s ongoing commitment to sustainability and resilient infrastructure. By upgrading treatment capacity, improving operational efficiency, and enhancing environmental compliance, the project delivers tangible benefits for local communities, ecosystems, and the wider UK water network.
Ferrovial’s approach to infrastructure investment emphasizes long-term value creation. Projects are designed not only to meet current needs but also to anticipate future challenges, such as population growth, climate change, and evolving regulatory requirements. By combining innovation, technical expertise, and environmental responsibility, Ferrovial and Cadagua are contributing to a more sustainable and resilient water sector.
SOURCE LINK: https://newsroom.ferrovial.com/
