Sewer main renewal can be unglamorous at the best of times, but can prove even tougher when undertaken in a public setting that requires pedestrian access. In situations like these, expertise, effective planning and consultation with stakeholders is critical to project success.
Regardless of the project type, areas with a high flow of traffic are challenging to manage and maintain. Sewers present unique challenges, with works often requiring heavy machinery that poses a risk to both public access and the integrity of existing infrastructure such as concrete paths.
A recent project at popular tourist location Mooloolaba, involved the relining of six consecutive lengths of DN450 and raising one access chamber, as well as cleaning and coating eight existing access chambers. Interflow worked with Unitywater and the local council to successfully manage the large numbers of pedestrians requiring beach and park access, and to undertake the works on steep, inaccessible bushland.
The relining process
In order to reline the existing pipes effectively, the lines were first cleaned using a recycler. To reduce cartage and use of water, cleaning was undertaken by a one position set up, incorporating two dingos which were positioned up the line. These were moved into position using a 100-tonne crane, along with the relining Kubota.
Because the site was located on a large area of parkland, multiple site setups were established, each requiring careful coordination and effective communications with stakeholders. The coating works and relining were undertaken in tandem, which made the most of the arranged closures and permits.
The importance of planning
Proving the importance of planning, the significant amount of preparation meant that there was minimal impact to members of the public and the environment. Environmental considerations such as species and habitat management are important in any renewal project, and were made a high priority, meaning that no harmful effects resulted from the works.
Flexible traffic and environmental controls are also critical to the success of renewal projects. With public footpaths impacted by the works in Mooloolaba, bog mats were required to control the subsidence of equipment. This protected the ground from recent rain, and protected the concrete paths from the weight of heavy machinery and equipment.
With effective planning, and using the right equipment for the job, the project was completed both on time and budget, without any impact to the Unitywater network.
For more information on Interflow’s sewer, stormwater and potable water capabilities, visit www.interflow.com.au.
Lauren Butler is the assistant editor for Utility Magazine. She’s based in Melbourne, Australia.