Briefing: Design for manufacture and off-site construction at Woolston Wastewater Treatment Works (UK)

Due to numerous site physical constraints and a tight construction programme at Woolston Wastewater Treatment Works, UK, conventional design and construction practices are being challenged to deliver the project using off-site manufacturing wherever possible. Through early supplier engagement and collaboration, the team has developed design solutions to suit off-site fabrication: most of the permanent civil elements are to be supplied in precast concrete; larger mechanical elements are being designed in a modular arrangement; and mechanical and platform suppliers are developing these elements in factory conditions and delivering to the site with pipework and electrical elements pre-installed. By working within a building information modelling environment, the team manages supplier three-dimensional model sharing within a common data area, ensuring governance and version control. This enhances integration between suppliers, enabling early clash detection and providing confidence in the production of off-site elements. The adoption of an off-site manufacturing strategy has accelerated construction delivery, providing programme and cost savings, and improved the level of safety on-site through reduced working at height, temporary works requirements, lifting operations and plant and vehicle movements.