The construction of an LRT system in Dublin will inevitably mean a certain level of disruption due to the necessity to divert essential services away from the path of light rail vehicles and the laying of rails along the routes. Construction disruption will apply to all routes to varying degrees depending on the characteristics of the alignment in particular locations.
For example, a substantial proportion of the Dundrum option would be off-street on the Harcourt Street railway alignment and disruption and congestion would, therefore, be relatively lower. In contrast, all the Ballymun option would be on-street with a consequent higher level of disruption during construction. There is also a question about the wisdom of closing Drumcondra Road, the main artery to the North, to build the light railway line, before the port tunnel has been built and could act as a relief road during construction.
The disruption-congestion issue is one of a number of matters being addressed in the independent comparative socio-economic evaluation.