ATKINS

Project: Liffey Valley Transportation Study

Client: Private Developer

Atkins Role:

Atkins were involved at the outset on the team developing the master plan and were responsible for traffic impact assessment and the design of roads and services.

The master plan includes an extensive road network with facilities for public transport, cyclists and pedestrians. A full grade separated interchange provides access to the N4 road. All of this infrastructure was put in place with the construction of the shopping centre. The consultancy brief also included the design of all 3500 car parking spaces and layouts.

The DTO’s highway (SATURN) and public transport (TRIPS) assignment models of the Greater Dublin Area (GDA) was modified for the purposes of the study, with the latter being converted into CUBE Voyager format to enable more sophisticated processing to be undertaken, and better quality visual outputs to be produced. The DTO transport model provides extensive detail within Dublin, with less detailed (buffer) coding toward the periphery.

The assignment models were also linked to a more detailed local area model - developed using the Paramics micro-simulation software package - to enable an assessment of the development impacts to be undertaken at an individual junction level. The Paramics model and map-based GIS images provided a high-quality visual perspective of the travel patterns for presentation at Public Consultation, which allowed the traffic impacts to be explained to non-specialists.

The outputs from the assignment and Paramics models were used to inform the Planning Application for the proposed development, which Atkins prepared in conjunction with the client. Initial feedback from stakeholder and public consultation, including discussions with South Dublin County Council and the DTO, highlighted the need for further evidence in relation to future year forecast mode splits. A bespoke spreadsheet-based mode choice model was developed, which allowed for a range of highway, public transport and non-transport related factors to be considered in generating mode splits. The model was full-automated and linked directly to the strategic SATURN and TRIPS models, to allow repeat iterations of travel costs and demands to be generated.

The revised Planning Application was submitted in March 2009. The robustness of the underlying business case and supporting technical evidence has been sufficient to allow provisional approval of the proposals, with full approval envisaged in autumn 2010.

» Full Transportation Projects List