In mid-2014, South Burnett Regional Council, located about two hours north-west of Brisbane, issued its largest ever sewer main relining and junction sealing contract over 18 km of relining works. The works were to be completed in the 2014-15 financial year with a preference for the relining portion of the project to be finalised before Christmas.
Laying it on the (re)line
One of the key challenges for the council was to ensure these works were delivered safely, quickly and to budget. Queensland-based Abergeldie Watertech Project Manager Christian Dummett said the scope of works and timeline was daunting. “We realised early on that to deliver all the relining works by December we would need to use both of our Queensland crews and additional resources from New South Wales,” he said. “Having access to additional skilled operators meant that in the early stages we could have three lining crews working concurrently. This ensured the target was met.” The scope of the work incorporated approximately 300 assets, and, like any job of this size, there were a range of challenges. These included keeping residents informed, keeping the crews fully utilised and ensuring safe and high quality works.
Bye-bye blockages
Abergeldie Watertech Queensland Operations Manager Paul Hymas oversaw the operation, noted that the company completed the relining works with multiple crews in multiple locations with no variations. “All customer questions were addressed promptly and efficiently,” said Mr Hymas. “Strong on-site supervision by Rob Alexander ensured any site risks and customer or council needs could be managed, including letter drops and door knocking to keep the end customer fully informed. The council was very supportive and provided great visibility of works and known issues which meant we could plan to succeed.” South Burnett Regional Council Services & Project Coordinator Matt Wyvill, who coordinates water and wastewater, said the project ran smoothly and with few issues. The project also highlighted the council’s commitment to ensuring long term sustainability and efficiency of wastewater infrastructure. “We have begun to decrease the number of blockages, surcharges and overflows while also decreasing infiltration and exfiltration of sewage into surrounding soils and significantly extending asset life,” said Mr Wyvill. “Trenchless Technology was determined as the most appropriate and cost-effective method to undertake this work. The benefits of trenchless relining technology for the council include the increased cost effectiveness of renewal instead of replacement, the low impact on surrounding areas, the ability to gain access via existing access chambers and minimal disruption to connected sewerage services.”
The trenchless lining method
Abergeldie Watertech offers a full suite of trenchless renewal methods including, UV-cured, cured-in-place pipe lining, spiral wound lining and the company’s EX fold-and-form method. Due to the nature of the works, and with pipe diameters ranging from 150-300 mm, the EX method was recommended. A PVC no-dig structural lining system manufactured in Australia exclusively for Abergeldie, the soft and folded EX is winched into the existing pipe and expanded using steam to form and fit tightly with the host pipe. The new EX pipe has no joints and provides the same strength, durability and long life of a new PVC pipe. Importantly, EX is able to line through displaced joints which significantly reduces the need for any civil works.