Impact of replacing a roundabout with smart traffic lights in Galway City

In 2013 Galway City Council started work on a project to remove the infamous Headford Road (Bodkin) Roundabout and replace it with smart traffic lights connected to a central traffic management system. A key aim of this project was to improve traffic flow on the main national route (N6) running through the junction and over the Quincentenary Bridge.

Bodkin Roundabout The project costing €1,863,482 went to tender with a total of 7 applicants and is listed on and in the database. The junction was infamous because this national primary route was getting blocked from time to time by cars backing onto the roundabout from the local Headford road shopping area including Galway Shopping Centre and the nearby retail park. This was leading to traffic delays on the main N6 route. 

As a multi-modal improvement scheme another key aim of the project was to  improve facilities for pedestrians and cyclists and provide for the future development of Public Transport. Prior to the upgrade of the Bodkin junction there were no controlled pedestrian crossings at the junction. Controlled pedestrian facilities are now provided on all arms of the junction providing safe pedestrian crossing facilities in the area. Cycle facilitates are provided on all approaches to the junction with 4,625 cyclists using the junction during the sample week in 2015. Bus priority was provided on the northern arm of the junction to minimise delays to buses using the junction.

The roundabout known locally as the Bodkin roundabout, was named after one of the 14 medieval tribes of Galway. It was mentioned regularly on local and national traffic reports as a key traffic blackspot. After many years of debate the local council in Galway City had decided to proceed with a smart traffic control centre, replacing some roundabouts with smart traffic lights. The removal of the Bodkin roundabout was a major flagship project. As a result of the works, it is no longer possible for cars backing up from the Headford Road to block the N6 junction.

Traffic flow over the Quincentenary bridgeBodkin Signalised

To examine the impact of the project, the Insight Centre for Data Analytics at NUI Galway examined the traffic flow data over the Quincentenary bridge before, during and after the road works which took place in 2013. We looked at the traffic flows for neutral weeks in 2012, 2013 and 2015 using detailed cordon count data provided by Galway City Council as part of the Your Data Stories EU research project.

Quincentenary BridgeWhat we found was that traffic flow over the Quincentenary bridge decreased by 4.7% during the construction work but increased by an average of 12.7% two years later (See table 1 below). We checked out a similar project on the old Dublin Road at Moneenageisha completed in 2009. Once complete the maximum deviation in terms of traffic flow at this junction was less than 4% year on year. Without any material changes to a junction, this is what we would expect. As such, it would appear that increases to traffic flow on the N6 in 2015 are as a result of the improvement works on the junction. 

In conclusion it appears that the project to replace the Bodkin roundabout with a smart signalised junction has facilitated greater traffic flows on the N6 based on the 2015 data. Preliminary data from 2016 also backs up this trend. The greater benefit though is that the new signalised junction is now part of a smart Urban Traffic Management Control (UTMC) system facilitating better traffic management throughout Galway city.

Traffic Data by Year


Tags:bodkin roundabout quincentenary bridge n6 galway