Background

Davyhulme Wastewater Treatment Works (WWTW) is the largest wastewater treatment plant in the North West, serving a population of over one million people. The site is of national significance, having played a pioneering role in the development of modern wastewater treatment more than 100 years ago.

United Utilities appointed Laing O’Rourke to deliver a multi million pound modernisation programme, designed to significantly enhance treatment capacity, efficiency and environmental performance, while ensuring the plant continues to operate throughout construction.

The challenge

The modernisation programme required extensive new below ground infrastructure to support major treatment upgrades, including:

  • Construction of six circular primary settlement tanks (PSTs)
  • A large activated sludge plant (ASP)
  • Ten circular final settlement tanks (FSTs)

Key challenges included:

  • Delivering large scale drainage and conveyance infrastructure within a live operational treatment works
  • Managing complex sequencing and interfaces across a constrained brownfield site
  • Minimising disruption while maintaining full treatment capability
  • Supporting Laing O’Rourke’s off site manufacturing and efficiency driven delivery model

The scheme also formed part of a wider remediation programme, transforming previously abandoned land and delivering long term environmental improvements.

The solution

Marshalls supplied bespoke precast concrete box culverts to support the upgraded treatment infrastructure at Davyhulme WWTW.

The culverts were engineered to meet the specific dimensional, hydraulic and structural requirements of the facility, enabling efficient conveyance of flows between the new treatment assets. Off site precast manufacture ensured consistent quality, precision and reliability, while supporting programme certainty and reduced on site activity.

The use of precast solutions aligned with Laing O’Rourke’s approach to modern methods of construction, helping to maximise the benefits of off site engineering and allowing installation to take place safely and efficiently within a live operational environment.

The outcome

The Marshalls precast box culvert solution is playing a key role in supporting the transformation of Davyhulme WWTW into one of the UK’s most efficient and sustainable wastewater treatment plants.

The completed works will deliver significant environmental benefits, including:

  • Improved treatment performance
  • Enhanced outflow quality
  • Protecting and improving water quality entering the Manchester Ship Canal

“Davyhulme is an iconic site where modern wastewater treatment was invented more than 100 years ago. We are keen to get started on this next development in the plant’s history, to ensure we continue to serve the people of Manchester into the 21st Century.”

Richard Sutton, Senior Project Manager at United Utilities

“Our ability to maximise the benefits of modern, off‑site construction and engineering techniques is central to our solution, meaning that we can deliver this complete scheme in a live environment with minimal disruption.”

Graham Flynn, Project Director at Laing O’Rourke