December 2, 2021

Metronet Byford Rail Extension

Rawlinsons were engaged on the Metronet Byford Rail Project to provide cost estimation services for both the Business Case and Project Definition Plan. As part of the works Rawlinson were embedded as part of the design team to provide ongoing strategic advice throughout the design work on cost estimation, procurement and risk analysis.

The project scope consisted of an 8km extension of the existing Armadale passenger line to Byford Town centre. A new station is to be built in Byford and the existing Armadale Station requires a very extensive rebuild.

During the business case phase of the works 6 different rail options along with 1 bus priority option were required to be estimated and fed into the Cost Benefit Analysis being undertaken by Ernest and Young. Options varied in terms of rail and station alignment with various mixture of below ground, at grade and elevated options.

Minimal design information was available to Rawlinsons during the business case and required Rawlinsons to heavily rely on their internal knowledge base to estimate with confidence the infrastructure components. No design was included for OLE, signalling and comms. Rawlinsons therefore relied on historical benchmark rates and our lead services estimators experience in building up composite rates to capture the value of these services.

One of the most challenging factors of the project and cost estimate was that throughout the duration of the works the existing Australind train line was to remain operational in the same rail corridor that the new rail line was being constructed in. Additionally, the existing Armadale Station was required to remain operational throughout the works. Both of these issues required extensive planning and constructability reviews. Rawlinson formed part of the project team that met weekly to work through each of these factors and provided strategic advice for each option or alternative. A number of meetings were held between Rawlinsons and the constructability consultant, Agonis, to further refine and understand the major issues caused by these factors. Following these meetings a detailed staging sequence was compiled and in turn the impacts of the sequencing was utilised by Rawlinsons to calculate the impact on productivity rates for certain works as well as capture the significant temporary works which included temporary 8km bi-directional signalled track for the Australind service to remain throughout.

Public Transport Authority | Metronet