Doka completes Queensland water security project
Doka Australia has delivered its engineering and formwork contract on Australia’s newest major water infrastructure asset, which has a storage yield capacity of 86,000 ML. The project was delivered by Sunwater, a government-owned corporation that supplies bulk water to over 5,000 customers across regional Queensland.
The Queensland and Australian governments have each contributed $191.6 million to the total project budget, with Sunwater funding the remainder.
Working with Acciona Construction Australia and McCosker Contracting, Doka supplied a complete formwork solution for the main spillway monoliths, abutments, and complex fishlock structure. Doka supplied design, materials, site supervision, and engineering support from concept to completion. The full supply level was set at 16.2 metres above the riverbed, the weir further included an impoundment length of approximately 60 kilometres, a spillway length of 202 metres, and a structural length of around 350 metres. The fishlock is approximately 26 metres in height, with complex chambers for valves, water intake, and fish passage.
In addition to its scale, the project was also located approximately an 11-hour drive from Doka’s closest yard, meaning workers were required to stay on-site, while logistics needed to be carefully calculated in order to maintain progress, particularly in terms of the pouring sequence, without incurring unnecessary costs.
By working closely with the client from the early stages of the project, Doka carefully calculated a formwork solution based on planning and overlapping the different areas to understand the required number of products, equipment, and manhours needed to deliver the project in the shortest possible time. This included using approximately 2,500 m2 of Framed formwork Framax Xlife panels and 440 single-sided Dam formwork D22 brackets at the project’s peak. By opting for a crane-operated solution in terms of repositioning, the combination of the Framax panels and the D22 provided enough adjustability to match the pour sizes and bracket distances, while taking into consideration the low concrete strength to allow for the pour sequence, while also ensuring fast repositioning. As a result, Doka utilised three-metre-high shutters and a 2x1.5 metre pour, prior to each reposition.
With the early involvement between Doka’s engineering team and the client’s construction team, the client met the objective and had a clear picture of the approach, resources, logistics, and engineering from the very start. As a result, the project team was able to adhere to the proposed workflow, while having the flexibility to change strategy around challenges as they arose. The site construction team confirmed, from a supervision standpoint, that Doka’s team provided all the support required from beginning to end, particularly in terms of compliance with the permanent and temporary works design. From a product perspective, the client was particularly impressed with the durability of the Framax Xlife panels, which remained in complete working order throughout the duration of the project.
Having started the project in July 2021, Doka was proud to complete its work on Rookwood Weir in November 2023, contributing to the countless projects that will support agricultural, industrial, and urban growth throughout central Queensland.
