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Trant complete Little Compton STW upgrade for Thames Water

The successful upgrade scheme improves operational performance and resilience at the works, and marks a strong return to delivery for Trant Engineering with Thames Water

By: Trant Engineering

Published: May 16, 2026

Trant complete Little Compton sewage treatment works upgrade for Thames Water

Under Thames Water’s Waste Asset Assurance Programme (WAAP), ageing plant at Little Compton Sewage Treatment Works (STW) near Moreton-in-Marsh required replacement. Trant Engineering was appointed to deliver the upgrade as part of their AMP8 Framework with Thames Water.

The scope included upgrading the existing maceration process to a modern fine screening process, removing ageing assets, installing a new inlet with screenings handling facilities, upgrading pumping infrastructure, and new MCC systems. A robust temporary flow management strategy ensured the site remained fully operational throughout the programme. Significant mechanical, electrical, ICA and civils works were undertaken, designed by Trant’s in-house design team.

Despite challenges presented by the compact, rural site, as well as poor weather conditions and localised flooding early in the programme, the delivery team successfully achieved the regulator date while maintaining the highest safety and quality standards.

Mark, Engineering Project Manager at Thames Water, praised the scheme:

“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.”

An in-house delivery model ensured control over quality, programme and safety. Trant’s Control & Automation team provided critical programme certainty and proved key to achieving the regulator date.

With strong relationships established and trust built through performance on site, the project provides a solid platform for future opportunities across Thames Water’s AMP8 programme.

For More Information, contact us at https://www.trant.co.uk

Inside one of the new glass-coated steel sectional clear water tanks - Courtesy of Trant Engineering

The new glass-coated steel sectional clear water tanks - Courtesy of Trant Engineering

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