Design and construction of the Toome bypass, Northern Ireland

This paper describes the construction of the Toome Bypass in Northern Ireland. The project presented many challenges to the client and the construction team: fitting the bypass into environmentally sensitive topography; innovative design-and-build contract procurement; partnering; construction of a landmark tied arch bridge; and construction of the bypass across soft alluvial clays in the Lower River Bann floodplain. Contract procurement sought to reduce tendering costs by selecting a preferred contractor who was then commissioned to develop a specimen design and target cost. The incentivised target cost contract imbued a value engineering culture, which drew heavily on the partnering and problem-solving ethos within the client and construction teams.