UEA was awarded a Design and Construct Pipe Bursting package for a local council in the Central Coast region of New South Wales, approximately 1.5 hours north of Sydney. The scope of work was spread over five sites throughout the region and included the supply of all materials, design and construction of new water mains using trenching and pipe bursting methods. More specifically, works included, but were not limited to:
- Preparation and submission of detailed designs for acceptance by the principal
- Replacement of five pipe bursting sites with lengths of 120 metres, 190 metres, 277 metres, 195 metres and 370 metres
- Installation of 84 new copper services from the new main to the property water
- Installation of 13 new mains connection points
The design process involved a number of meetings with the Council’s operational staff, ensuring that UEA could design and construct a system with the client’s genuine input. UEA’s previous experience in designing pipe bursting works in this way have ensured a smooth and swift approval process.
Before each pipe bursting operation commenced the Council shut down each water main for approximately five hours, and during this five hour window UEA also installed all connection details. The connection detail involved installing hydrants and isolation points on either end of the project. Temporary mains were installed to maintain water supply to all residents impacted by the main being taken out of service. Once the temporary main was made live, the existing main between the isolation points was then shut down and the pipe bursting process of replacing the old main commenced.
Pipe bursting is a process in which solid rods are inserted through the existing pipe and connected to an expanding head and new PE pipe above ground at the end of the section. The pipe bursting rig then pulls the rods back out of the pipe and at the same time, the expander head ‘bursts’ the existing pipe and installs the new pipe in its place. On this project, UEA used a Grundoburst 800G which has a pullback force of 769kN.
Upon completion of the bursting process each house service was connected to the new main. Tees, additional hydrants and link ups were also completed. Once complete, all new mains were then tested, cleaned, flushed and commissioned.
UEA has a commitment to protecting the environment, and managing the potential environmental impacts from the Water Mains Renewals Package was top priority. UEA provided an Environmental Management Plan for the project highlighting potential environmental risks presented by the project and the relevant risk mitigation and management procedures. UEA also created site specific Sediment Control Plans for the five locations, identifying key areas to be affected by the works and associated control measures.
The newly installed main was pressure-tested, swabbed, flushed and ultimately passed water sample testing, meeting all applicable standards without issue. Overall, UEA’s management and crew worked in conjunction with all stakeholders to provide a successful and environmentally sustainable project.