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Trant Completes Little Compton Sewage Treatment Works Upgrade for Thames Water

Phil Black - PII Editor 23 seconds ago

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Wastewater treatment upgrade improves resilience and operational performance

Trant Engineering has successfully completed a major upgrade at Little Compton Sewage Treatment Works (STW) for Thames Water, delivering improved operational performance and long-term resilience at the rural wastewater treatment site near Moreton-in-Marsh.

The successful project also marks an important return to delivery for Trant Engineering within Thames Water’s capital investment programme, reinforcing the company’s position as a trusted delivery partner across the UK water sector.

The scheme was delivered under Thames Water’s Waste Asset Assurance Programme (WAAP), which focuses on replacing ageing infrastructure and improving the reliability, efficiency and compliance of wastewater treatment assets across its network.

Major sewage treatment works upgrade delivered under AMP8 framework

As part of Thames Water’s AMP8 Framework, ageing plant equipment at Little Compton STW required replacement to maintain operational reliability and support future performance requirements.

Trant Engineering was appointed to undertake the full upgrade programme, with works designed and delivered using the company’s in-house engineering and project delivery capabilities.

The project scope included replacing the existing maceration process with a modern fine screening process designed to improve screenings removal efficiency and overall process performance.

Additional works included the removal of ageing assets, installation of a new inlet structure with screenings handling facilities, upgrades to pumping infrastructure and the installation of new motor control centre (MCC) systems.

A comprehensive temporary flow management strategy was also implemented to ensure the sewage treatment works remained fully operational throughout the upgrade programme, minimising disruption to ongoing wastewater operations and maintaining environmental compliance.

The scheme involved extensive mechanical, electrical, instrumentation, control and automation (ICA) and civils works, all designed by Trant’s in-house design team.

Overcoming challenging site conditions

The delivery team faced several operational challenges during the project due to the compact nature of the rural site and difficult weather conditions experienced during the early stages of the programme.

Periods of poor weather and localised flooding created additional logistical and construction challenges. Despite these conditions, the team successfully maintained progress and achieved the required regulator date while upholding high standards of safety, quality and operational performance.

The project highlights the growing importance of resilient wastewater infrastructure upgrades as UK water companies continue investing in ageing treatment assets, environmental performance improvements and operational reliability under AMP8 investment programmes.

Thames Water praises collaborative delivery approach

Mark, Engineering Project Manager at Thames Water, praised the delivery of the scheme and the collaborative working approach demonstrated throughout the project.

“A tremendous effort from the team. For me, this has been a standout project, delivered with real commitment and collaboration throughout. The Trant team maintained strong progress even under challenging conditions, and their efforts are greatly appreciated.”

The project was delivered using Trant Engineering’s in-house delivery model, helping maintain control over programme management, quality assurance and site safety throughout the works.

Trant’s specialist Control & Automation team also played a critical role in ensuring programme certainty and successful completion ahead of the regulatory deadline.

Strengthening future AMP8 opportunities

The successful completion of the Little Compton sewage treatment works upgrade further strengthens the working relationship between Trant Engineering and Thames Water as AMP8 investment programmes continue across the UK water industry.

With strong working relationships established and trust built through delivery performance on site, the project creates a solid foundation for future collaboration across Thames Water’s wider AMP8 programme.

As water utilities continue prioritising wastewater treatment resilience, environmental compliance, infrastructure modernisation and operational efficiency, projects such as Little Compton STW demonstrate the importance of integrated engineering expertise and collaborative delivery models within the UK water and wastewater sector.

Trant Engineering Limited
Rushington House, Southampton, SO40 9LT
T +44 (0)23 8066 5544
www.trant.co.uk