Keidges Road Reservoir

Project Scope

DWW Engineering was engaged to design, fabricate, and install a new aluminium roof structure, access stair tower, roof top platform and Davit Arm for Queensland Urban Utilities, Keidges Road Reservoir. This project was part of a wider plan to rehabilitate the reservoir and repair significant leaks to improve the water supply to the surrounding community.

Although DWW had designed and fabricated aluminium structures in the past, a structural project on a water reservoir was both a new and exciting challenge for the business.

Challenges and Approach

Constructed in 1990, the ground-level 15 megalitre tank, with an impressive 45m internal diameter, presented the team at DWW with several problems to solve.

Notwithstanding its bespoke, aluminium structural design specifications, the brief stipulated that the roof system is a conical or 4-way sloping roof, as opposed to triangular ‘pizza-like’ segments. Furthermore, the design also had to prevent any contamination risk from water ingress or vermin entering the reservoir.

Due to the aluminium material specification and complex geometry of the final design, the drafting of this project proved to be extremely challenging. Standard libraries and automation provided by modern CAD packages were not able to be used in this design, as every connection was unique.

Adding to the complexities, the aluminium sections were not available in the lengths required, so they had to be extruded specifically for this project. With manufacturing boundaries being pushed, this meant design lead-times were also compromised. To meet the project deadlines, materials had to be ordered before the detailed design was fully completed.

Outcome

The design was a performance-led initiative. The tank was surveyed using 3D laser scanning and the design model was checked against the actual tank dimensions. This process proved to be an invaluable exercise, as we identified several irregularities in the tank which were then accounted for during fabrication. A high level of fabrication accuracy was achieved with the assistance of an in-house CNC Beam Line. This resulted in the structure fitting perfectly, eliminating any variances and costly overruns during installation.

Despite the challenges faced in solving complex design issues, the project was successfully executed with zero safety incidents.  With continuous stakeholder engagement and high-quality standards throughout, DWW successfully met the project’s primary objectives of reduced contamination risk and an extended service life of the asset through enhanced design and quality construction.

Both our client and Queensland Urban Utilities were extremely satisfied with the inclusive design management process, along with the final roof aesthetics and overall project outcomes.