The Dawson Highway connects the industrial centre of Gladstone to the Leichhardt Highway and provides a direct link to southern capital cities. CMC was awarded the contract to construct a new 4.5 kilometre, four lane road through the Calliope Range near Biloela, approximately 60 kilometres south-west of Gladstone.
Works included bulk excavation through rock requiring blasting on extremely steep terrain, installation of 19 major drainage culverts, challenging tie-ins under live traffic, unbound pavements, bituminous surfacing, and major landscaping of over 70,000 trees, including an extensive temporary irrigation system. CMC also constructed piled retaining wall, extruded concrete barrier, and two bridges during the project.
Despite the project’s complexity, CMC maintained a safe and stable batter slope through complex fractured rock strata, while still preserving the proposed aesthetic appearance of the uniform shotcrete design.
Sustainable Impact: CMC constructed in an environmentally sensitive natural vegetation reserve, which required stringent environmental controls during the bulk earthworks to eliminate sedimentation runoff on the steep grades. A combination of rock check dams, silt fences, sediment ponds and the early revegetation of disturbed areas were successfully used. Resources found onsite were reused during construction of the project to minimise waste. All trees that were cleared at the commencement of the project were mulched and reused at the end of the project in the revegetation of the site compound area.
Safety: The project contained many hazards which were successfully managed during the execution of the project. CMC’s high regard for the significance of working safely, and their rigorous management of workplace health and safety on the site, left the principal with considerable peace of mind during construction of the project, and produced an end result with a reportable safety performance that any contractor would be proud of. Examples of safety initiatives include the use of temporary water filled barriers at the base of rock cutting batters to protect plant and personnel from rock falls during slope stabilisation works, and the implementation of specific work procedures to enable the safe compaction of asphalt pavement shoulders adjacent to the edges of steep batters.
Innovation: CMC developed a blast design that enabled all hard rock to be drilled, blasted and excavated safely within 25 metres of a major high-pressure gas main.
Collaboration: CMC established a collaborative approach to resolving project challenges. CMC workshopped high risk activities with the Department of Transport and Main Roads project management team and subcontractors to ensure the construction methodology, hazards and controls were correctly identified and implemented. The workshops involved all of the project organisations and provided representation at all levels to ensure that factors such as safety, design, aesthetics, compliance with legislation and constructability of each associated task were considered.
