Multiple Road Safety Audit Stages
Client: AECOM
In 2011 PMCE Ltd. were commissioned by AECOM to conduct Road Safety Audits (RSAs) on the proposed Bothar na dTreabh (N6) Multi-Modal Corridor Improvement Scheme.
The proposed Bothar na dTreabh (N6) Multi-Modal Corridor Improvement Scheme extends between Browne Roundabout and Lynch Roundabout to the north of Galway City. The proposed works involved the upgrading of the existing scheme roundabouts to signalised junctions to include facilities for pedestrians and cyclists and the upgrading of pedestrian and cyclist facilities along the N6 between junctions.
The Scheme was divided into 4 Phases and each Phase was subjected to separate Road Safety Audits.
Phase 1 of the proposed scheme included works on the N6 links between Browne Roundabout and Bodkin Roundabout, including works at Newcastle Road junction, and between Kirwan Roundabout and Font Roundabout.
The proposed works included some resurfacing of the existing off-road footway and cycle facilities between the existing junctions, the incorporation of “Ladder & Tramline” tactile markings at the commencement and termination of the adjacent pedestrian and cyclist facilities including periodic “reminder” tactile markings.
The Newcastle Road junction was to be improved and the signals altered with improvements to the cyclist provision on the approaches to, and through, the junction, and pedestrian facilities including pedestrian crossings of the N6.
The Stage 1, or Preliminary Design, RSA was carried out in June 2011 following a visit to the site on the 3rd of March 2011 and a review of the Phase 1 drawings. The Stage 2, or Detailed Design, RSA was also completed in June 2011
Phase 2 of the scheme included the upgrading of Lynch Roundabout at the eastern tie-in of the scheme. The Stage 1 and Stage 2 RSAs of Phase 2 were also completed in June 2011.
Phase 3 included the upgrading of Font Roundabout and Morris Roundabout and the Stage 1 and 2 Road Safety Audits were completed in May 2011 and August 2011 respectively, following a site visit and review of the drawings for this phase.
Phase 4 of the scheme, which involved the upgrading of the existing Bodkin Roundabout, underwent a Stage 2 RSA in January 2011.
The proposed works primarily consisted of the removal of the existing Bodkin Roundabout at the junction of the N6, the R338 and the Headford Road. The roundabout was replaced by a signal controlled junction and required the closure of the existing access from the Galway Shopping Centre, which accessed directly onto the Bodkin Roundabout circulatory carriageway.
Alternative access arrangements for the Galway Shopping Centre were proposed from both the R338 and the Headford Road, south of the N6/R338 junction. Revised internal circulating arrangements for vehicles were required within the Galway Shopping Centre car park to cater for the revised access/egress arrangements.
The proposed works also included the provision of signalised pedestrian crossings of all arms of the new junction, on-road cycle lanes and off-road cycle tracks and a bus lane on the N6 Headford Road southbound approach to the junction.
On the section of the N6 Headford Road north of junction a signalised junction was to be provided at the existing left in-left out access for Cúirt na Coiribe. This signalised junction would permit right turn exits from the residential area and also signalised egress movements from the Dunnes Stores car park on the opposite side of the road. The proposed works also required alteration to the existing public lighting, directional & statutory signage and to some existing utilities and statutory undertaker plant.
On the R338 Sean Mulvoy Road it was proposed to provide a break in the existing median at the egress from the Sean Mulvoy Commercial Centre to facilitate right-turn manoeuvres out of the commercial centre.
Following the implementation of the proposed works Stage 3 RSAs were carried out for each Phase.
The Stage 3 RSA for Lynch Roundabout took place on the 8th of December 2011 and involved undertaking a site visit during hours of daylight and darkness and involved the Audit Team walking, driving and cycling the scheme.
The Stage 3 RSA for Phase 1 (the upgrading of Newcastle Road Junction close to the western tie-in of the scheme and minor works on the link between Kirwan Roundabout and Font Roundabout) was completed following a site visit by the Audit Team on the 17th January 2012.
A Safety Review was carried out at Coolagh Roundabout as a result of the identification of a number of operational and road safety related issues at the junction and a site visit took place on the 8th March 2012.
Coolagh Roundabout is located at the junction of the N6 National Road and the R446 Regional Road at Bothar na dTreabh, east of Galway city centre. Coolagh Roundabout forms part of the N6 Dublin-Galway route. Coolagh Roundabout is the first at-grade junction that westbound drivers on the N6 have to navigate when travelling between Dublin (outside of the M50) and Galway along the N4/N6 and is the only location along the route where drivers are required to slow, or come to a halt, with the exception of the toll plazas at Enfield and Ballinasloe.
The junction consists of a three arm roundabout with two lane entries and exits on all junction arms. Dedicated left turn slip lanes have been provided for traffic turning left onto the R446 from the N6 westbound, and for N6 southbound traffic turning onto the N6 eastbound, removing the need for this traffic to travel through the roundabout junction.
Following the Safety Review of the roundabout in March/April 2012 a number of alterations to the approaches and the junction layout were proposed in order to address safety concerns. The proposals included:
- altering the radius of curvature for each entry to the roundabout circulating carriageway,
- widening the circulating carriageway width,
- revised roadmarkings and signage on the approaches to, and at, the junction.
A number of ancillary works were required as a result of these measures including alterations to the existing safety barriers, drainage & other items of road side furniture.
Stage 2 and Stage 3 RSAs were carried out in October 2012 and May 2013 respectively. The latter involved a site visit by the Audit Team on the 14th May 2013 when the Team walked, drove and cycled through the scheme.
A Stage 3 RSA was carried out on Phase 3 of the scheme (Font and Morris Junctions). These former roundabouts were upgraded to signalised junctions. The Audit Team visited the site during the hours of daylight and darkness on the 5th of July 2012.
A Stage 1/2 Road Safety Audit for the proposed altered accesses on Sean Mulvoy Rd. and Headford Rd. was completed in September 2013 following a review of proposals for two altered access arrangements within the proposed scheme extents, which included: –
- providing a right turn exit from the Retail Park onto the Headford Road, south of the Bodkin Junction; and
- providing a right turn exit from the Fort Retail Park onto the Sean Mulvoy Road.
The final Road Safety Audit completed by PMCE Ltd. as part of the Bóthar na dTreabh Multi-Model Corridor Improvement Scheme was the Stage 3 RSA of Phase 4 (Bodkin Junction). The Audit Team visited the site on the 22nd of November 2013 and audited the site for safety issues in relation to motorists, pedestrians and cyclists.