1.6 kilometre triumph an Australian first
The largest horizontal directional drilling installation of its kind in Australia, successfully completed on the Sunshine Coast.
22 January, 2018
Pipeline Drillers has accomplished the highly anticipated 1.6 kilometre Nicklin Way section of the new Caloundra Sewerage Pipeline, said to be the largest and longest horizontal directional drilling (HDD) installation in Australia.
In March, a small specialist HDD crew began working six days a week from an entry site located behind Industrial Avenue, drilling adjacent to Nicklin Way and extending north towards Beerburrum Street.
Unitywater Engineer Project Manager Louis de Groot said this part of the project had the greatest risk of impacting on residents and major roadway users, which led Unitywater to opt for horizontal directional drilling for its ability to construct and install pipelines with minimal disruption.
“Hundreds of residents live in Aroona including 100 properties within proximity to Nicklin Way, by choosing a trenchless installation method we were able to reduce the number of residents directly impacted by 70 percent,” Louis said.
“Working from the surface at one entry and exit site, the small footprint required to construct this pipeline almost eliminated disruption to road users of Nicklin Way, and greatly reduced the number of trees cleared within the corridor, allowing Unitywater to improve the performance and capacity of the sewerage network while minimising disruption to both the community and environment.”
The Sunshine Coast crew together with the new Herrenknecht HDD250t and American Augers DD1100, powered a dual-rig operation to drill through extremely hard rock at depths as great as 35 metres and using a multi-pass method enlarged the borehole in increments to its final diameter of 1200 millimetres. While this took place, the 900 millimetre high-density polyethylene pipes were poly welded together into six 270 metre strings and laid along the back of Industrial Avenue.
Enduring harder than expected rock, a mammoth effort saw work continue into early November before preparation for pipe pull-through began. The 500 tonne American Augers pulled in 550 metres per day which included a three-hour pause to position pipe on rollers, weld strings together, and position ready to go, with the entire pipeline successfully installed within 72 hours.
Pipeline Drillers not only employed a high performing HDD crew but also a number of new technologies for this landmark drill, including the $1.4 million new generation Herrenknecht HDD250t, a new downhole tool, and the Kemtron 1500HD2 fluid recycling cleaning system.
Next month, construction partner Dormway will return to site just south of Beerburrum Street to tie-in the new pipelines, while Pipeline Drillers commence the last horizontal directional drill of the project at Caloundra Road to complete the 2.5 kilometre pipeline.