Trinity Stage 30 Civil Works and Stage 31 Earthworks

Engaged on the Trinity Development for LWP after a successful tender bid with consultant GHD. The contract was for the construction of ongoing subdivisional stages over a twelve month period.

  • Client:

    Northern Corridor Development Ltd (LWP)

  • Location:

    Alkimos WA

  • Construction Period:

    Jan 15 – Aug 15

  • Key Elements:

    • Project management
    • Civil construction
    • Subdivision construction
    • Earthworks
    • Remediation
    • Clearing
    • Demolition
    • Underground services
    • Sewer reticulation
    • Stormwater installation
    • Water main installation
    • Roadworks
    • Concrete
    • Client Liaison

Project overview

DM Civil was engaged on the Trinity Development for LWP after a successful tender bid with consultant GHD. The contract was for the construction of ongoing subdivisional stages over a twelve month period. The first stage undertaken in this agreement involved the construction of two separable portions, Stage 30 civil works with earthworks and the earthworks component for Stage 31 with the civil works to follow at a later date. The site was spread over one kilometre with the main site office located an additional kilometre from the work site.

The tight programme required completion within twenty four weeks. This included earthworks comprising 14.4 hectares of clearing and 145,500 cubic metres of cut to fill with 35,000 in rock. There were 1.9 kilometres of retaining walls and 400 metres of decorative fencing. The services included 1.2 kilometres of sewer, 1.1 kilometres of stormwater drainage, 2.1 kilometres of water reticulation and 2.3 kilometres of common trenching for gas, communications and electrical services. The roads were spread from one end of the site to the other and included 18,500 square metres of pavement and 4,800 square metres of footpath.

DM Civil completed this subdivision to a high standard while working to a very tight construction programme with challenging conditions.

Significant achievements and benefits

DM Civil strived to accommodate the client’s requests to carry out miscellaneous minor works outside of the original scope of work. This included additional retaining walls, multiple carparks for the nearby sales office and display village and additional footpaths and earthworks in the previous stages surrounding the site.

With a much larger than anticipated volume of rock encountered, the project team was under pressure to perform to maintain programme. Considerable additional resource was mobilised to site to deal with the rock and the site team pushed hard to maintain the already tight programme. With persistence and good planning, the delay due to the additional rock was managed by the site team and delays were minimised. The completion of the main stage of subdivision was not impacted by the additional rock encountered.

The project team worked to keep the disturbance to the neighbouring properties to a minimum and through consistent communication and prompt responses to complaints received, were able to maintain a good rapport with the nearby residents. This liaison was key to the success of
the project where the client and consultant were relying on DM Civil to maintain a harmonious relationship with existing residents subjected to close proximity construction activities.

Significant liaison with service authorities was required to effectively manage a total of 35 changes and connections to existing live services across the project. This included 8 live connections by the Water Corporation to each sewer and water main and 19 changes or live connections to the electricity network by Western Power. These elements added to the pressure on the programme critical path which required innovative measures to be implemented by site management.

The client expressed appreciation of DM Civil’s readiness to mobilise additional resources as and when required to undertake additional minor works in the surrounding completed stages whilst still delivering the required results on the main contract stages.

Download the Trinity Stage 30 Civil Works and Stage 31 Earthworks project report