Rawlinsons were contracted by the Metronet office to provide a Class 5 cost estimate at the business case stage of the project for various options for the LXR project in Victoria Park. The two options put forward at business case were as follows:
Option 1A – 3km of two track railway with rail over road with elevated stations at Carlisle and Oats Street
Option 2 – 3km of two track railway with rail under road with underground stations at Carlisle and Oats Street
Rawlinsons provide a full total out turn cost for both P50 and P90 certainly levels. Cost estimates included direct costs, in-direct costs, client costs, contingency/risk calculations and escalation costs.
The site was particularly constrained due to the existing Armadale line occupying the rail corridor as well as public roads running adjacently and also key road intersections along the proposed route. Additionally, there is a high voltage Western Power distribution service that runs parallel to a significant portion of the works.
Rawlinsons estimating methodology was to utilise the detailed design provided for the MEL project to calculate composite benchmark rates for a lot of the structural works as the design work completed was minimal. Stations were estimated using elemental measurement and pricing. In-direct costs were estimated on a first principle basis as due to the extent of the staging works normal percentages allowances would not cover the extended time related preliminary costs for the works.
Due to the locality of the works there was a significant amount of existing utility and service relocations works required. Rawlinsons undertook dial before you dig co-ordination and identified all known services that were likely to require removal or relocations. The scope of works was reviewed and verified by the design team and the Rawlinsons team provided detailed cost estimates for each service including temporary works allowances and utility provider premium mark ups.
Rawlinsons were engaged to provide a value engineering review of the proposed design and scope for the preferred option 1A by the Project Management Office. Rawlinsons (W.A.) compiled a list of potential cost saving items and other project opportunities. A meeting was held with the key stakeholders, this exercise resulted in cost savings of $50m being achieved due to the following:
· Removal of additional escalators at Oats Street Station
· Reduced roof area to both stations
· Changing of platform tiling to pavers
· Rationalised ramp construction methodology
· Additional project opportunities factored into contingency calculation
