January 1, 2022

Metronet Karnup Station

Rawlinsons were contracted to provide cost estimation and value engineering services for the proposed new railway station on the Mandurah line.

The project scope included forward works: bulk earthworks, retaining walls and some in-ground services, Station works including: Access roads, station in embankment with underpass, adjustment of rail track and services, park and ride facilities and a bus interchange. Rawlinsons provided both Class 4 and 3 estimates for the Business Case and PDP phases respectively.

A challenge Rawlinsons encountered on the project was the fact that it was proposed for the existing rail line to remain operational throughout the works with only a few minor 72-hour weekend shutdowns for major works. Rawlinsons calculated productivity rates for works that needed to be carried out at night or in short windows of opportunity. This included the mobilisation of a piling rig for the construction of the underpass. Due to the existing OLE it was programmed for these works to happen at night in 8 hour shifts. Rawlinsons (W.A) captured the cost of the temporary works including significant earth embankment for the piling rig and also extremely low productivity rates in tasks such as earthworks, piling, concrete and roofing.

Further to the estimating services Rawlinsons were part of the team that undertook a Scope and Engineering Review (SER). The purpose of the SER was to challenge the proposed design to see if better efficiencies could be achieved in the proposed design and also to clearly determine where the scope of works stopped for the new station and started for the Transit Orientated Development (TOD) as a large part of the site footprint was planned for future development opportunities. This service provided a 15% reduction in the Total Project Outturn Cost Estimate. 

Public Transport Authority | Metronet