Kier has been appointed by Thames Water to deliver a £66m design and construction project at Mogden Sewage Treatment Works (STW) in Isleworth, just outside of Twickenham Stadium.

Mogden STW is a resilience project that will include the design and construction of significant modernisation and improvements to the existing facility, providing additional resilience and capacity, including onsite energy generation, improving the capacity of preliminary treatment and improving the resilience of the sludge and digester streams in preparation for AMP8 works.

Mogden is Thames Water’s third largest treatment works, spanning 55 hectares and serving around 2.1m people. It was built in the 1930s and this project will upgrade include existing tanks as well as the construction of new tanks, replacement of key mechanical and process equipment and a site-wide upgrade of electrical panels.

Mark Pengelly, group managing director at Kier Infrastructure, said: “We have a long history of delivering projects and services for Thames Water and look forward to continuing our relationship with this project. It is a highly complex and specialised project and the team will be working in a live environment, across multiple locations of the site.

“We will be working with AECOM as design partners and we have selected key Kier and AECOM personnel for their experience and knowledge of STW and complex large-scale civil engineering. They will bring a tried-and-tested approach, having collectively worked together over the past six years, at Deephams STW.”

Francis Paonessa, Thames Water’s capital delivery director, said: “Our investment in Mogden Sewage Treatment Works will be essential in modernising one of our most urban treatment works. It will play an essential part in our work to reduce the impact on our neighbours, while ensuring Mogden can handle the expected increase in waste from London’s growing population in the future. This scheme is just part of a wider investment plan to ensure our sites can continue to provide our essential service to millions of customers across London and the Thames Valley.” 

This award builds on Kier’s longstanding partnership with Thames Water, having secured a place on its £2.6bn AMP7 Capital Programmes Framework last year, as well as providing planned and reactive services through the Infrastructure Alliance.

In addition, Kier’s recent involvement in the upgrade of the 50-year-old Deephams Waste Water Treatment Works in Edmonton North London saw the delivery of the project on one of London’s largest facilities, without expanding the site footprint or interrupting the daily flow of sewage. At the same time, there was a strong focus on sustainable and innovative building techniques such as modern methods of construction, increased operational safety and extensive hydraulic modelling to provide significant capacity improvements to the sewage treatment works.