Major improvements to the M1/Westlink, Northern Ireland

The improvements to the heavily congested urban corridor on the M1/Westlink through Belfast were for many years the highest priority for Northern Ireland's Road Service. Capital funding was secured through a public–private partnership and the £104 million improvement works were committed as part of a design, build, finance and operate (DBFO) contract. The improvement works included widening the existing road to provide 4·5 km of dual three-lane carriageway, grade separation at two major junctions, bridge replacement, river diversions and significant public utility diversions. The paper demonstrates how the project team tackled the problems, highlights the techniques used and the key construction activities, and details the use of state-of-the-art technology which was a first in Northern Ireland. It reflects on the lessons learnt. The success of the project was reinforced not only by the leading Belfast newspapers but also the Comptroller and Auditor General in their assessment of the scheme, which was completed ahead of programme and within budget.