17th - 18th September 2025
New Installation Stream Schedule
Registration and Welcome Coffee (Foyer)
Kick off No-Dig Down Under 2025 with a warm welcome! Join us for registration and a coffee to start your day right, connect with fellow attendees, and get ready for a full day.
Opening Address (Auditorium)
A welcome from ASTT Secretary Trevor Gosatti.
Trenchless Technologies for a Resilient Future: Decarbonizing, Digitizing, and Deploying Smarter Infrastructure (Auditorium)
As urbanisation accelerates and climate resilience becomes imperative, trenchless technologies are emerging as essential tools for modernising underground infrastructure. This talk explores a transformative approach to utility design and deployment, centered on a “Triple Mandate” to decarbonise, digitise, and deploy smarter systems. Through case studies and global best practices, we examine how digital twins, AI-driven simulations, and next-generation construction methods can dramatically reduce emissions—up to 90%—while enhancing operational efficiency, safety, and adaptability. We also spotlight the role of trenchless innovation in enabling underground electrification, supporting smart cities, and mitigating disruptions from extreme weather events and cyber threats. With policy support, workforce development, and continued R&D, trenchless technologies are poised to redefine how cities build resilient, future-ready infrastructure.
Local Water Authority Panel (Auditorium)
This panel brings together leaders from local water authorities to discuss current challenges, emerging opportunities, and the strategies shaping the future of water utilities.
Modern Jacking Pipe Design and Liners – Optioneering for longer service life, reduced installation risk, and lower carbon footprint for both pressure and gravity applications
Modern jacking pipe design has evolved to meet the increasing demands for cost efficiency, durability, and risk reduction in trenchless pipeline installations. A critical aspect of this evolution is the selection of appropriate liners, which play a key role in enhancing structural performance, corrosion resistance, and overall service life. This paper explores the benefits and trade-offs of various jacking pipe liners, including Glass Reinforced Plastic (GRP), High-Density Polyethylene (HDPE), Polyvinyl Chloride (PVC), and Cement Mortar Lined and Epoxy Lined Steel. Through a comparative analysis, the study examines the impact of these materials on life cycle costs, hydraulic performance, installation complexity, and long-term reliability. The concept of "optioneering" is introduced as a structured approach to evaluating liner selection based on project-specific requirements, balancing technical, economic, and environmental considerations. By integrating modern materials and engineering best practices, this paper provides valuable insights into optimizing jacking pipe designs for improved performance, sustainability, longer drive lengths, curved alignments, fewer shafts while reducing installation risk.
Drilling solutions for offshore wind foundations and export cable landfalls
The development of renewable energies is the focus for future energy supply. Large offshore wind farms are to be constructed and connected to the grid. Due to the public environmental awareness, smart installation methods are required for fast and safe installation of foundations and cable landfalls. In addition to limitations in certain ground conditions, conventional pile-driving has a deep environmental impact and reaches its limits with increasing turbine sizes and water depths. Today, the Offshore Foundation Drilling (OFD) technology provides a completely drilled installation of offshore foundations. Both full-face cutting systems and partial-face excavation concepts are utilized, depending on the foundation type and diameter to be installed. While partial-face excavation solutions are primarily used for drive-drill-drive installations, the OFD full-face (FF) machines are mainly considered for socket drilling, providing high drilling performance and considerably reduced acoustic emissions. For the connection of offshore wind farms to the onshore grid, microtunnelling methods offer considerable environmental and safety benefits and a high degree of flexibility for project planners and contractors. Landfall sections of export cables are usually located in sensitive coastal areas with high environmental regulations. Re-mote-controlled microtunnelling methods like Pipe Jacking and Direct Pipe are used to safely install protective pipes and tunnels with subsequent pull-in of the export cables. Drilling works are carried out underground, from onshore to offshore, in or-der to reduce marine construction costs and to preserve marine wildlife and sea-water quality. This presentation will share different technological approaches for trenchless landfall construction and offshore foundation drilling.
Horizontal Directional Drilling Delivers Positive Outcomes for the Gold Coast Light Rail Stage 3 Project
The Gold Coast Light Rail Stage 3 (GCLR3) project involves the construction of a new light rail from Broadbeach in the north, along the Gold Coast Highway, to Burleigh Heads in the South. The 6.7km extension includes new dual-track light rail, 8 new light rail stations, new bus connections, and new and upgraded intersections and crossings. The alignment is through the high-density urban area of the Gold Coast, and is surrounded by commercial and residential properties, with the Gold Coast Highway providing a major north-south thoroughfare along the coast. The extensive stakeholder constraints for the project where a key driver for the selection of construction methods. Trenchless technologies have been adopted for a number of service relocations and new service installations across the project to minimise the impacts (and reduce risks) associated with the various external stakeholders, including road users, businesses, residents, and asset owners. Horizontal Directional Drilling (HDD) was determined to offer the least impact solution for much of the service crossings given the relatively small construction footprint. However, the high-density urban nature of the project presented many challenges still for HDD construction. Each crossing of the Gold Coast Highway required entry and exit pits, laydown areas, and pipe stringing areas. The successful delivery of more than 40 HDD road crossings within the 6.7km stretch of the Gold Coast Highway, including bore diameters up to 700mm in challenging sand geology, has proven the benefits of the methodology, particularly with key third party asset owners in busy urban environments.
Carrier Pipe Selection - High external / Low internal pressure application finding pipe's ugly duckling
Water pipe, High voltage power cables and Fibre Optic Cables (FOC) need to be run between two sides of the project, with the most difficult section being a large elevation drop dividing the two adjacent sites. The eastern and lower site or “Lower pad” and the western or “Upper pad”. Three HDD (Horizontal Directionally Drilled) Boreholes have been drilled connecting the two sites, Lower pad is at 630mAMSL (metres Above Mean Sea Level), Upper pad is at 1194mAMSL, boreholes are 2240m long, starting at the Lower pad at 5 degrees inclination increasing to 18 degrees then returning to 14 degrees at the Upper pad. Challenges include length of the boreholes, internal/external pressure head (54.9Bar), conductivity of 33kV power cable, pressure head of water and time. Pipe materials considered: HDPE, Steel and GFRP. HDPE is user friendly, non-conductive, non-corroding, low cost, however it has inadequate pressure bearing capacity. Mild steel is cheap, user friendly, strong, however it corrodes. GFRP is non-conductive, corrosion resistant, heat tolerant, and has a high-pressure bearing capacity (both burst and crush). It does have drawbacks, it is not user friendly (difficult to thread together), and it is relatively delicate requiring manual handling. The boreholes were lined using steel casing grouted into the ground. This sacrificial steel casing was proposed to protect the Glass-Fibre Reinforced Polymer (GFRP) carrier pipe from abrasion during installation. GFRP pipe is a good carrier pipe material to run HV power cables and water down a steel cased HDD borehole in a high-pressure environment.
A Case Study in Direct Pipe® Thrust Load Prediction
The Direct Steerable Pipe Thrusting (DSPT) technique, which includes Direct Pipe®, is considered a hybrid of horizontal directional drilling (HDD) and microtunnelling methods. It is a surface-to-surface trenchless method that involves thrusted installation of steel pipe along a typically curved vertical alignment, similar to HDD. Like microtunnelling, soil excavation is performed using a remote controlled closed-face slurry tunneling machine located at the leading end of the thrusted pipe. Publications addressing the prediction of DSPT thrust loads have used calculation methods that are commonly either used to predict HDD installation pull loads or those used to predict linear pipe jacking thrust loads. The paper presents measured thrust forces for five (5) DSPT installations completed in North America in silty and sandy clay and till material with gravels and cobble conditions. The paper compares these measured thrust forces to estimates made using the HDD calculation approach and provides commentary on the appropriateness.
Jansz IO HDD Project
The Jansz IO HDD Project is one of the largest HDD projects completed in Australasia. Completed between 2020 to 2024, it presented challenges throughout the planning and execution process. This project consisted of the new installation of 3x 600m DN630 HDPE conduits for Chevron Australia as part of the Jansz IO Subsea Compression Project and Barrow Island Upgrade Project. From the initial stages of the project, constraints were identified with the mobilisation and planning due to the classification of Barrow Island as a Class A Nature Reserve. Additionally, the geotechnical composition of the ground was highly fractured with frequent and significant changes in composition, along with full losses of drilling fluid. The experienced drilling conditions deviated from the interpolated borehole data leading to challenges with steering and installation. This paper will provide a summary of the challenges experienced and the actions taken, along with their effectiveness, when drilling in such challenging conditions. The project resulted in successful installation of two of the critical casings for gas plant continuation and subsea connection, and one abandoned installation. This paper will provide an insight into working in some of the most challenging HDD conditions experienced in Australia, and cover the lessons learnt and improvements from engineering to construction.
Welcome Coffee and Networking (Foyer)
Start Day Two off on the right foot by connect with peers, catching up on yesterday’s highlights, and fuelling up for another day.
Latest International Trenchless Trends Panel Session (Auditorium)
Discover what’s shaping the future of trenchless technology by joining industry experts as they discuss the latest international trends, innovative techniques, and emerging solutions that are transforming the way we plan and deliver underground projects.
Application of Tunnelling Technology to the HDD Sector for Full Loss of Drilling Returns Crossings
This submission will detail the customisation and innovation associated with utilising a modified tunnelling mixing system for HDD applications where full drilling losses were predicted. It outlines the process from concept design through to testing and implementation throughout the Jansz IO HDD Project. Three 36-inch 600m crossings were drilled in highly fractured ground, leading to complete losses from MD60 to MD600. Given the constraints associated with working in a Class A Nature Reserve, saltwater bio-degradable drilling fluids were required. This required a mixture of two polymers (Xanthan & Guar) and 3 additives (Soda Ash, Defoamer & Biocide) to be mixed at high volumes with predictable and repeatable compositions. The project team consulted with suppliers of a tunnelling mixing system and composed a customised solution to modify tunnelling technologies for the HDD industry These modifications were field tested in Italy to ensure the system was suitable for use on the critical project. The resulting outcome was a mixing system capable of high volumes (2x 100kL / hour systems) with +/- 1kg accuracy on additives using load cells on dosing. Additionally, through augured loading of polymers, the requirement for manual handling was eliminated, along with the risk of spills and environmental contamination. This solution can now be utilised on upcoming major projects in the Australasian market and demonstrates a solution for the HDD industry for drilling with full losses. Additionally, it highlights the capability for increased crossover within the trenchless industry for collaboration on unique and challenging problems.
HDD - Real World Pipe Pull Forces
Specialist HDD contractor CDS New Zealand Limited recently completed multiple water pipeline crossings beneath the Taihiki River, linking Glenbrook Beach and Clarks Beach in Auckland. Commissioned by Watercare Services Limited, the project replaced a failed marine-laid watermain serving the growing Glenbrook Beach community. The solution involved three horizontal directional drilling (HDD) crossings over a 760-metre alignment, installing one 140mm and two 280mm OD SDR7.4 PE100 pipelines. The alignment was shifted westward from the original route to avoid unstable, eroding cliff faces and the alignment kept deep to protect the historically and culturally significant Waiau Pa area. Geotechnical investigations informed drill profiles reaching RL -19m beneath the riverbed, targeting the East Coast Bays Formation. Due to logistical constraints—specifically the 45-minute trip between the HDD rig and pipe stringing sites—the 140mm pipeline was repurposed as a drilling fluid return line. One key challenge was pulling small-diameter polyethylene pipes over long distances. CDS conducted stress analysis using ASTM F1962, which informed the SDR7.4 pipe selection. For academic comparison, the team also used the PRCI method. Variations in predicted stresses between the two raised concerns, prompting the use of a smart strain gauge between the pulling head and swivel. This enabled real-time monitoring of pull forces and annular pressures during pullback. The project allowed CDS to evaluate three long HDD installations simultaneously. Real-time data from the strain gauge supported adaptive strategies and offered valuable insight into the accuracy of HDD stress prediction models, contributing to ongoing industry refinement.
Structural Design of GRP Jacking Pipes
Glass Reinforced Plastics (GRP) jacking pipes are now very commonly installed throughout Australia and New Zealand. These pipes are supplied with a very large range of stiffness classes, but design methods are not well established or well understood. This paper examines how the stiffness class should be selected based on both temporary and permanent design loads. Specifically, the paper considers how permanent loads should be designed for and whether the GRP jacking pipe should be considered as a flexible, rigid or even semi-rigid pipe. It also examines whether existing standards such as AS/NZS 2566.1 or even AS/NZS 3725 can be used for the design of such pipes and if so, what design criteria should be adopted and how design to these standards might compare with the German Standard DWA-A 161. The paper includes a number of design examples. Many km of such pipelines are constructed every year and it is very important to the industry and asset managers alike that pipes with appropriate stiffness classes are selected for both a cost-effective installation and that the installed asset continues to adequately perform for its intended design life.
The Evelyn Street Trunk Stormwater Upgrade project
The Evelyn Street Trunk Stormwater Upgrade project consists of approx. 300m of DN1200 concrete drainage pipe to be installed via microtunnelling methods in Newstead, QLD. The project includes modifications to existing pit structures at the upstream location, a new, large custom networks structure and discharge to the Brisbane River. The project includes a number of challenges, including: • Large number of internal and external project stakeholders; • Bespoke delivery and contract model, and challenging procurement factors; • Geotechnical and groundwater conditions; • Significant alignment constraints based on discharge requirements and existing services. The project construction environment is within a dense urban area. The conditions of council approval for an age care facility required construction of the trunk drainage line. Due to design and procurement issues, the works were initially placed on hold by the developer, and construction of the drainage line has commenced in May 2024, following completion of the high-rise age care residence. This paper provides details associated with the specific technical and procurement challenges associated with both the pre-construction and construction aspects of the project. This includes the impacts of design suitability during tendering, third-party asset owner interfaces, procurement, local assess and space-proofing, and community and special interest group management.
Snowy 2.0 – Marica Road West HDD: Elevating Engineering and Innovation in the mountains
The Marica Road West Horizontal Directional Drilling (HDD) project is a critical component of the Snowy 2.0 renewable energy initiative in Kosciuszko National Park, New South Wales, Australia. The project involved the design, drilling, installation and securing of three separate 2,240 metre long steel casings via HDD for power, water, and communication lines. The Marica Road West HDD is notable for its technical complexity, primarily due to the environmentally sensitive escarpment, with a 580-metre elevation change between the entry and exit points, making it one of the most challenging HDD projects attempted and completed in Australia. This extreme elevation difference presented significant engineering challenges, including managing downhole pressure fluctuations, ensuring bore stability across variable geological formations and controlling high groundwater inflows. To overcome these challenges, Michels Trenchless implemented innovative techniques, including a dual-rig intersect method for enhanced control and reduced stress on the drill string and the deployment of custom rotary diverters for effective groundwater management. The project was executed within the environmentally sensitive Kosciuszko National Park, necessitating strict environmental controls and a custom-designed groundwater containment system to prevent ground disturbance, fluid migration, and ecosystem impact. Zero-spill execution protocols were enforced through secondary containment barriers and real-time fluid pressure monitoring. The successful completion of the Marica Road West HDD demonstrates significant advancements in HDD capabilities, particularly in managing extreme terrain and complex geological conditions within highly sensitive environmental areas. These findings are important to the trenchless industry as they provide valuable insights and methodologies for tackling similar challenging projects.
Direct Pipe Developments in New Zealand: Hybrid and Short Pipe Launch
Since its introduction to New Zealand in 2018 McConnell Dowell has keep its equipment busy having now completed six Direct Pipe drives, installing over 14Km of pipeline. Including three wet recoveries and two world records for drive lengths (1.9Km and 2.1Km). Lessons from previous drives have driven change and since no two projects have the same ground conditions, restraints or client requirements the methodology today has been adapted and now used differently to the first Direct Pipe drive in 2018 at Arm Bay. Pushing the boundaries of what can be done with has led to the development of a “Hybrid” methodology to install GRP pipe, and “short pipe” launches for constrained sites. Techniques that will have relevance in Australia. This presentation will briefly cover the projects that have led to these developments and hopes to widen the industry understanding of Direct Pipe. A trenchless method often perceived as an HDD competitor when it actually fits between HDD and micro-tunnelling. It aims to reduce risks for client and contractor by doing things smarter, not necessarily cheaper. Using a decade of experience in New Zealand and Asia, combining operational lessons, internal Engineering review and leveraging a strategic relationship with Delve Underground. We have developed a pragmatic, collective approach to both technical and client issues. This has implications for the wider trenchless industry as it is an example of an evolving methodology and as an industry that must evolve. Other methodologies will come along its important that our industry challenges the norm.
Vacuum Microtunnelling: Creating a New Trenchless Horizon
Vacuum microtunnelling is reshaping the future of pipeline installation. Traditionally, trenchless methods have been reserved for specialist crossings, while open cut dominated broader pipeline works. However, advances in systems like AdaptX and modified AXIS machines — which combine high-performance microtunnelling with vacuum extraction — are now tipping the scales. This paper explores how vacuum microtunnelling is expanding the capabilities of trenchless technology, delivering cost competitiveness with open cut at depths beyond five metres in greenfield environments, and at even shallower depths where excavation complexity increases, as is typically the case in urban settings. It highlights how trenchless construction can now offer superior accuracy, speed, and minimal ground disruption across a wider range of projects. Drawing on field data, equipment testing, and project comparisons, the paper demonstrates why trenchless methods should increasingly become the default choice for pipeline installation. It also examines how this shift is giving contractors greater confidence to invest in advanced trenchless equipment, knowing that trenchless construction will capture a growing share of future infrastructure work. By embracing vacuum microtunnelling, the trenchless industry can drive better project outcomes, reduce environmental and community impact, and bring lasting value to the broader community — paving the way for a future where trenchless reigns supreme.