Maxibor, Lamb Island 330x500

Good practices for HDD project management

Overarching this platform is a strong project management process which is applied across the full lifecycle of the horizontal directional drilling (HDD) projects it undertakes.

“Applying good practices to the management of HDD projects is essential from when the project information becoming available through to close out meetings,” says Maxibor CEO Rodney O’Meley.

“Getting it right from whoa to go is a big part of the success of Maxibor and is reflected in the respectful relationships we have been able to widely build across the trenchless industry and broader infrastructure sector.”

So, what are the key elements of good practice project management in the HDD world? They are really no different to those in other parts of project land.

However, it is important to have the experience to identify and understand the key matters you need to manage. The vision to identify and realise opportunities will also help optimise project outcomes for all stakeholders.

The key areas of good practice project management on HDD projects include:

Geotechnical data

Ground conditions are a high-risk area for HDD projects.

The ability to interpret geotechnical reports, proximity of bore sampling to designed bore hole alignment and rock strength testing methods used are just some of factors which need to be considered before design and delivery commences.


Most value can be added here. A good design engineer who can understand the relevance of geotechnical data and trenchless calculations is an essential part of the project team.

Extensive in-field delivery experience on challenging complex HDD projects is even more valuable.

Stephen Loneragan of HDD Engineering ably fits this description and has been a big part in helping successfully deliver HDD projects across the globe.

“Understanding client’s needs, technical information and resources to be used to deliver the project are essential to developing and communicating a design and construction methodology which minimises risk and optimises value,” says Mr Loneragan.

“By combining extensive field experience to design and engineering at the early project development phase, it has the ability to greatly improve constructability, which ultimately provides lowest cost and importantly, lowest risk outcome for clients.”


The key areas of contractual focus include ensuring the scope reflects what has been priced, time limits and liquidated and other damages are reasonable and causes of delay and latent conditions are either allowed for in the price as risk or will be allowed causes for time and/or cost variations.

Maxibor prepares a contracts departures schedule for each project which facilitates early conversation and a smoother project management process.

Risk and opportunity management

Maxibor has developed a comprehensive risk and opportunity register which covers the safety, environment, quality and HDD design and delivery risks.

The register of risks and opportunities is considered for each project and those more relevant to the project are actively managed.

Safety and environment

The inclusion of HSEQ personnel in the project management process is essential from the start to the finish.

Significant productivity gains can be achieved on the delivery of projects through having people safe, the environment protected, and plant and equipment well maintained and safely operated.

Scheduling of works and project tasks

The construction schedule is the roadmap to the delivery of the project. Knowing what needs to be done and when and by whom is a big part of the project.

Maxibor uses a project task register to capture key activities which need to be undertaken on each project.

Critical tasks are closely managed and regularly considered by the project management team. Understanding critical tasks and progress facilitates informed communication with the client and other stakeholders.


The main delivery resources for an HDD project are people and plant – Maxibor manages availability of staff through having multiple drill crews who can work across the maxi and other rigs.

Having one of the largest HDD fleets in Australia – four maxi-rigs, two midi-rigs and five smaller rigs along with cleaning systems, pumps and vac units overcomes many of the challenges of having the right plant available to deliver a project.

Supply chain

Having well established relationships with the supply chain overcomes many of the scheduling issues which can arise around material supply and provision of services such as pipe welding.

These relationships also help when unexpected or unusual issues arise with ground conditions, and urgent supply of special drill fluid ingredients is needed.

Stakeholder engagement 

Communication with stakeholders is easy if good project management practices are being applied throughout the project.

Applying all the above key good practices will strengthen the relationship with key stakeholders as communication can be both timely and informative.

This creates an environment which address challenges in a cooperative manner and helps to optimise outcomes for all.


The project management process needs to be conducted in a manner which has a view to attracting future business.

“It is important that trenchless industry promotes its capabilities through demonstrated successful delivery of projects,” says Maxibor National Business Development Manager David Turner.

“This is best achieved if there is a close connection between the client, project team and marketing/business development people to ensure that useful marketing content is captured and disseminated.”

Lesson learned

Steve Gibson of Devonian Group Projects has managed some of the largest infrastructure projects in Queensland and has been assisting Maxibor in further strengthening its project management framework.

“Every project has an end but we should never lose sight of that we are all on a continuous improvement path,” he says.

“Stakeholders taking time to reflect on the delivery of a project provides the means to make the next project even better.”

As a knowledge company Maxibor is more than happy to discuss its good practice HDD project management practices with others across the infrastructure sector.  

For more information visit the Maxibor website. 

Boretech D24x40S3 for Vermeer WA & NT

Boretech leading WA’s HDD utility installations

WA-based Boretech Contracting started as an installer of underground services for Telstra and the National Broadband Network but has since expanded and secured long-term horizontal directional drilling (HDD) contracts for a range of utility projects.

Read more

construction workers closing site with hazard tape

Victorian Government shuts down construction

Due to concerns about COVID-19 case numbers and transmission risk, the Victorian Government has announced a two-week shutdown for construction in metropolitan Melbourne and other local government areas currently in lockdown.

Read more

900 mm concrete pipe on Ashburton drain diversion

Pezzimenti completes drain diversion

The company uses its own Pezzimenti-developed laser-guided microtunnelling systems and specialises in free boring, sleeve boring and pipe jacking methods. 

Last week, Pezzimenti Trenchless completed a job for Transcend Plumbing, having been engaged to construct a council drain diversion at Markham Ave in Ashburton. 

The project was tendered by the City of Boroondara to divert flow to allow for a new government housing estate to be constructed on the site.

The team used a Pezzimenti Laserbore with 1,050 mm diameter to bore through clay ground conditions to a depth of 3 m, before installing a 900 mm reinforced concrete pipe using the free bore method. 

This was the company’s first project for Transcend, and according to Pezzimenti Director Joe Pezzimenti, it set a great precedent for future working relations. 

“The project was a successful collaboration between Transcend and Pezzimenti,” he said.

“All OH&S requirements were catered for and Transcend provided a great working site with good access and conditions.” 

For more information visit the Pezzimenti Trenchless website. 

Hard hat image

Featured company: Prime Drilling GmbH

For more than 20 years, the company has been recognised for its expertise in the HDD field, for using first-class materials in the development of low-maintenance and robust drill rigs. 

Prime Drilling’s offerings include astute knowledge-how in drilling techniques, high production quality, and excellent service.

Today, there are more than 110 Prime Drilling HDD rigs in successful operation around the world. 

Alongside a comprehensive product range of HDD and MDD technologies, Prime Drilling also offers a range of professional services, including remote maintenance and product advice backed by a qualified team. 

Click here to view the company’s directory listing. 

For more information visit the Prime Drilling GmbH website. 

Auckland city skyline

Upgrades to Auckland stormwater outfall

McConnell Dowell has announced construction on the new Ports of Auckland Outfall Upgrade Project will begin in late 2021. 

The company was awarded the contract by Auckland Council in 2019 because of its extensive track record in marine outfall construction using trenches methodologies. 

The project will construct the last and most challenging section of the Stanley Street catchment network to mitigate future flood risks. 

Works will include culvert strengthening, excavation, chamber and outfall construction, and tunnelling to a maximum depth of 20 m. 

The new outfall will increase the stormwater capacity and provide greater resilience to Auckland’s downtown infrastructure, particularly for the Britomart Railway Station. 

A new 270 m inverted siphon pipeline will be installed using microtunnel boring machine (MTBM) with a diameter of 3 m. 

The outfall alignment will run under Quay Street behind the Port of Auckland and the old stormwater culvert will also be repaired and reinstalled.

Once completed, the new outfall will improve the resilience of Auckland’s downtown infrastructure. 

For more information visit the McConnell Dowell website. 

Herrenknecht sponsors No-Dig Down Under

Through innovation and development, Herrenknecht has expanded its equipment range with specialised pipeline installation technologies to become one of the most significant companies in the industry.

Its AVN microtunnel boring machines (MTBMs) are the world’s most common machine for the installation of 400 mm to 4 m pipelines via microtunnelling and have facilitated thousands of projects.

Herrenknecht MTBMs can be applied in almost all ground typologies with precise control, even with small radii in vertical and horizontal curves.

The company’s horizontal directional drilling (HDD) rigs offer pull forces from 80 to 600 t, along with a range of HDD tooling including full face hole openers (FFHO) for single-pass large diameter reaming stages, weeper subs and downhole jet pumps. 

Herrenknecht’s Direct Pipe technology is used the world over for the single-pass installation of steel pipelines from 20 to 60 inches (508 to 1,524 mm) in difficult ground conditions, while its Pipe Thruster offers 300 to 750 t push/pull force to assist challenging HDD installations of longer pipelines and larger diameters.

Another patented technology, Herrenknecht’s Pipe Express® method works as a rapid, semi-trenchless, cross country pipeline installation system for 30 to 60 inches (762 to 1,524 mm), while the company also offers the E-Power Pipe® technology, which uses a microtunnel boring machine with jet pump (AVNS) for longer drives in small diameters.

Herrenknecht will sponsor the Official Exhibition Opening at No-Dig Down Under on Tuesday 8 March 2022.

For more information visit the Herrenknecht website.

To plan your attendance, visit the No-Dig Down Under website.


Featured company: D.J. Mac Cormick Contractors

Its specialist team of personnel has more than 40 years of experience and a reputation for excellence, substantiated by its numerous awards Australia-wide and internationally.

The company has a successful history having completed thousands of projects for government utilities, local authorities and private industry.

Whatever location, contractual arrangement and challenges, D.J. Mac Cormick Contractors aims to consistently deliver a safe, high-quality and cost-effective product on time and to budget.

Click here to view the company’s directory listing. 

For more information visit the D.J. Mac Cormick website. 


CRL under Auckland city

Works on hold for Auckland supercity

Watercare commenced works on the Central Interceptor project in Māngere last month, with the 14.7 km sewer tunnel to run from Grey Lynn to the Māngere Wastewater Treatment Plant and expected to be completed in 2025. 

Once completed, it will be the longest bored wastewater tunnel in New Zealand. 

According to the Executive Program Director Shayne Cunis, the project came to a  halt in recent weeks due to recent COVID-19 outbreak. 

Mr Cunis said that under the public health response legislation, basic operations were still permitted, but expects the project’s operations to be able to return to “normal” when Auckland shifts to alert level 3.

Greater onsite restrictions for staff will still be in place after the alert level is downgraded, with workers having to maintain social distancing and onsite “bubbles”.

He said the latest lockdown will affect the time it takes to complete the project, but he remains confident it can still be delivered on budget.

Across town, developments on the $4.4 billion City Rail Link have also been stalled. 

A spokesperson from the Ministry of Business, Innovation and Employment (MBIE) said they were unable to confirm what operations will look like for the CRL and Central Interceptor projects under level 3 restrictions. 

For more information visit the Watercare website. 


Ballarat CBD sewer line installed

Ballarat’s two largest sewer lines, Ballarat East and Ballarat South, were constructed almost 100 years ago.

These sewer lines are now in the process of upgrade, where both will be duplicated over the next 3-5 years with the new lines installed parallel to the existing sewer.

Central Highlands Water (CHW) has invested $25 million into the major project, and the upgrade is intended to service the Ballarat community for another 100 years.

Stage one of the project commenced in mid-Aril 2021 with open excavation and microtunnelling in the CBD area.

Microtunnelling techniques were used where possible to minimise ground disturbance; however, attempts at Little Bridge Street were unsuccessful due to ground conditions and excavation was instead necessary.

CHW was to install a 600 mm diameter sewer pipe 4.5 m beneath Peel Street, from Scott Parade to Little Bridge Street.

CHW announced the completion of the CBD section on Friday 8 August, with construction now continuing on Peel Street heading south.

CHW Project Manager Mick Dwyer said the work on the CBD section had been both crucial and challenging.

“This critical section through the Ballarat CBD was always going to be one of the most complex, due to the proximity of Peel Street businesses to the sewer path plus the difficult ground conditions beneath the surface.”

“The need to change our approach at the Little Bridge Street intersection was unforeseen, even with the significant amount of investigation works completed prior,” he said.

For more information visit the Central Highlands Water website.

Planning approval granted for desalination plant, pipeline

This week, the New South Wales Government approved Hunter Water‘ s plans for a desalination plant at Belmont as a drought response measure.    

The plans are a reaction to water storage levels in the Lower Hunter, which recently reached its lowest point in nearly 40 years.  

The plant is designed to produce up to 30 million L of drinking water per day in response to drought.   

This follows in the wake of the most recent drought of 2019-2020, which saw the introduction of water restrictions for the first time in decades.   

The Hunter Water team worked closely with the NSW Government, key stakeholders, and the local community, and planning approval was issued yesterday by the Department of Planning, Industry and Environment.  

The desalination plant, once constructed, will receive direct ocean seawater intake by piping seawater from 1 km offshore.  

The intake structure would be installed at a depth of approximately 20 m, extending 5 m above the ocean floor, and the pipeline will be installed under the ocean floor via a trenchless tunnelling method. 

Hunter Water Managing Director Darren Cleary said desalination is one of the few water supply options that is not dependent on rainfall.  

This would mean that with the construction of a desalination plant, Hunter Water could continue to supply communities irrespective of changes in weather or climate.  

While the likelihood of having to construct the plant is low, it was imperative that Hunter Water sought planning approval, should it need to build in the near future.  

“Planning approval for the Belmont desalination plant gives us an additional tool to help close our supply gap during periods of drought, providing Hunter Water with the capacity to provide up to an additional 30 million L of water each day,” said Mr Cleary.  

Hunter Water said the project approval was supported by comprehensive environmental impact investigations, which evaluated the potential impacts that could be mitigated through detailed design and delivery.  

These assessments found that a trenchless method would have the least significant impact on marine life, while the intake would also be designed to reduce the chance of marine life being drawn into the pipeline.  

Construction of the desalination plant could take three years.  

For more information visit the Hunter Water website 

Rob Carr TBM

Rob Carr delivers keynote presentation

Recently, representatives from highly regarded contractor Rob Carr gave a keynote presentation at the Victorian Tunnelling Centre, located at Holmesglen Institute’s Chadstone campus.  

 The speakers included Rob Carr Managing Director Damien Maitre and Construction Manager Andrew Scarr.  

The session welcomed more than 100 attendees, made up of students from Nossal High School and representatives from all five Level Crossing Alliances (South Eastern Programs Alliance, Metropolitan Roads Program Alliance, North Western Program Alliance, Western Program Alliance, Southern Program Alliance).  

The Level Crossing Removal Project comprising these alliances was established in 2015 and is forecast for completion in 2025.   

The Victorian Tunnelling Centre trains approximately 5,000 workers each year in underground construction and maintenance, including the operation of tunnel boring machines.  

This will support the thousands of apprentices, trainees and cadets who will deliver Victoria’s pipeline of infrastructure projects. 

The recent presentation was part of an invitation extended by Fulton Hogan to participate in their Communities of Practice seminar.  

Rob Carr operates around Australia and New Zealand as a contractor and subcontractor in underground infrastructure capabilities and was recently contracted to complete work in difficult ground conditions for Fulton Hogan.  

For more information visit the Rob Carr website. 


Adept microtunnelling works on track

Adept specialises in the supply and installation of water and sewerage drainage pipelines around Victoria.  

The company said it has dedicated months in planning to major water, sewer and drainage upgrades in Truganina in consultation with clients Becon Constructions, BP, Charter Keck Cramer and City West Water.   

‘Our highly advanced microtunneling equipment and highly skilled team [were] the reason Adept were chosen to deliver this project,’ Adept said on social media.  


The civil and water infrastructure specialist provides contracting services within the water and sewer industry and is the only company in Victoria delivering civil and microtunneling projects on a large scale.  

Previous projects by the company have included the West Gate Tunnel sewer relocation, the construction of Plantation Road storage bypass tank, and the sewer relocation as part of the redevelopment of St Kevins College.  

Truganina is located 22 km west of Melbourne’s CBD.  

The upgrades will include the use of microtunneling techniques to construct a new large sewer and water mains 500 m from the new development in solid basalt rock.   

For more information, visit the Adept Civil Group website. 

McConnell Dowell gets creative on NZ storage pipeline

The complex project involves the construction of a new stormwater storage pipeline which will help provide a better life for people, birds and marine life in the region. 

The St Marys Bay Area Water Quality Improvement project secured another win with the completion of the last tunnelling drive at the end of 2020.

Hinehōaka, the project’s microtunnel boring machine (MTBM), successfully completed more than 1 km of microtunnelling in less than six months. 

The 1,120 m storage pipeline, which includes a marine outfall, was constructed in three separate tunnelling drives using pipe-jacking methods.

The new pipeline will reduce wastewater overflows to St Marys Bay and Masefield Beach by 95 per cent. 

The high flows after rain events will be stored in the new larger capacity pipeline and pumped back into the sewer network for treatment when there is capacity.

As well as reducing overflows, once complete the new marine outfall will discharge to a location far away from places where people swim. 

Two shafts were constructed in council parkland at the bottom of the cliff face to accommodate each tunnelling drive and a third shaft needed to be constructed in the narrow streets around St Marys Bay.

This shaft was carefully and cleverly designed to be able to retrieve the MTBM from a 3.8 m diameter shaft, 25 m below ground.

”We couldn’t have asked for a better result after the completion of our last tunnelling drive at the end of 2020,” said McConnell Dowell Senior Project Engineer Grant Maclean .

“We set a bold target of getting the drives finished and machine out of the ground before Christmas, so it was a great team effort to complete it in time.

“The team comprised of some really experienced members, as well as some new ones who were eager to learn. 

“It was great seeing them help each other out and pass on some of that knowledge to the younger ones.

“The crew should be proud of what they achieved, especially finishing the job in a highly sensitive area, with almost no noticeable effect to stakeholders.”

The London Street shaft under construction.

Responding to challenges

Each tunnelling drive had its own unique challenges but one of the major challenges the project team faced was tunnelling very close to, and underneath, restored villas worth millions of dollars in one of Auckland’s oldest suburbs.

To mitigate stakeholder issues and concerns, the project set up a ‘SiteHive’ unit to collect data while the MTBM was operating. 

The unit continuously collected noise, dust and vibration monitoring readings from the worksite and this data helped proactively manage consent compliance, as well as record the impact of the operations.

When noise reached predetermined levels a photo and sound recording were taken to capture the activity onsite. 

This constant monitoring meant the team could ensure construction activity operated within the consent conditions and any exceedances were investigated to see what could be done differently to ensure compliance in the immediate future.

Another technical feat on this project has been the design, construction and sinking of the marine outfall pipe.

The outfall, constructed by McConnell Dowell’s New Zealand marine team, had been cleverly built to withstand the 12-hour pipe-tow journey from Kaiaua, Firth of Thames to Auckland. 

What made this significant milestone a challenge was the on-water installation of the ballast blocks.

Although on-water installations have been done before, the Creative Construction™ difference on this project had been the design and construction of the custom-made frame attached to the side of the barge. 

This meant there was less pipe bending during the installation, while ensuring sufficient space on the barge to store the 70 ballast blocks and the crane that was carrying out the operation. 

Once the ballast blocks were installed, the 460 m HDPE pipe was floated around from its temporary mooring off Westhaven Marina to its final position adjacent to Masefield Beach.

Although the sinking of the pipe was an effortless seven-hour procedure, the accuracy of the sinking was mainly due to the measurements taken by site engineers two days prior. 

Starting from 3am, the team started measured the pipe every hour for two days to see how it expanded and contracted in different temperatures and they noted the pipe dimensions that were recorded at the beginning of the day were different at the end of the day.

By using these calculations, they could give a close-to-perfect hypothesis of where the pipe would land at completion of the sinking. 

As a result of these studies, there was only a slight discrepancy of 50 mm off the predicted landing.

According to McConnell Dowell Project Manager Matt Beswick, sinking the pipe and connecting it to the end of the newly built stormwater tunnel was quite a technical feat. 

“It had been twelve months of meticulous preparation and design.

“Sinking the outfall pipe was very impressive and precise work requiring both large scale machinery and human involvement, and we’re very proud of everyone who worked on this project,” he said.

Health and wellbeing has also been a huge focus on this project, as all three tunnelling drives were carried out by the team working in shifts over a 24-hour, five days per week work period.

To educate the team around mental health, McConnell Dowell invited Mates in Construction, a program aimed at improving mental wellness and reducing suicide in the construction industry, to run sessions onsite with the crew. 

An overhead shot of the Pt Erin shaft with the MTBM ready to bore.

The St Marys Bay Area Water Quality Improvement project is the first McConnell Dowell site and fourth site in New Zealand to be Mates in Construction accredited. 

The scope of works includes:  

•Building a new 1.2 km long, 1.8 m diameter stormwater storage pipeline and 500 m of additional wastewater pipeline connections from 900 to 1,050 mm internal diameter.  

•Constructing three shafts at Pt Erin, St Marys Road Park and the corner of London and New Streets. 

•Performing three tunnelling drives to connect the shafts (and manholes) and create a tunnel to the pump station and out to the outfall location in the Waitemata Harbour. 

•Assembling a 468 m long 1,600 mm diameter high-density polyethylene (HDPE) marine outfall assembled in Kaiaua, Coromandel then towed 90 km to Auckland.  

•Building a new pumping and screening station and odour control unit in the Pt Erin Park shaft.

Construction began in January 2020 and is scheduled for completion in mid-2021.

For more information visit the McConnell Dowell. 

This article was featured in the June 2021 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

WATCH: New Melbourne sewer pipeline on track

The Yarra Valley Water (YVW) project involves the construction of a 9 km sewer pipeline between Donnybrook and Beveridge in Melbourne’s north.

On completion, the pipeline will incorporate up to 14 branch sewer connection points to service future developments and collect and transfer wastewater from the existing Wallan Sewage Treatment Plant.


JAYDO reported this week that the microtunnel boring machine has just completed the fifth of six drives, marking another significant milestone for the project.

The pipeline is being constructed along the western side of the Melbourne-Sydney railway line north of Minton Street, then crossing the railway line and hugging the eastern side of the rail line to its southern end in Donnybrook.

Construction is on track for completion later this year with the new sewer pipeline to be in operation shortly after.

For more information visit the Bothar website.

Vale Aurelio Pezzimenti

He passed away peacefully surrounded by his beloved family.

Aurelio was a truly remarkable man and a claimant to the title of ‘The Father of Australian Microtunnelling’.

In the mid to late 1980s, in partnership with his brothers Gilbert and Frank, Aurelio developed the vacuum extraction microtunnelling system which is ideally suited to Australian ground conditions.

If imitation is the sincerest form of flattery, then many flattered Aurelio over his life time. Many have built their own vacuum microtunnelling systems based on Aurelio’s original ideas and concepts.

In 2013, Aurelio was awarded the ‘Person of the Year’ by the ASTT for his outstanding contribution to the industry.

The 1981 film ‘Chariots of Fire’, tells the story of Eric Liddell, who won a gold medal at the 1924 Paris Olympic Games.

In the film, Liddell is credited with saying ‘God made me for a purpose, but He also made me fast, and when I run, I feel His pleasure’.

 Aurelio was not gifted to run fast but was given a brilliant mind and using his mind gave him pleasure.

Aurelio’s passion and joy were evident when he got on a roll and outlined his latest idea, innovation or project.

The words flowed as he grabbed the nearest piece of paper to sketch out his thoughts.

He was able to envision components assembled and the end product at work long before the drawings were started.

Aurelio was also a problem solver.

He was never stuck for a solution to a site problem.

I knew Aurelio as a friend for 30 years and for 25 of those I worked closely with him.

In all that time Aurelio never lost his temper, raised his voice nor blamed others for mistakes made.

Eric Liddell saw his purpose NOT as a runner but to serve the people of China, the country of his birth.

After the Olympic games, Eric rarely mentioned the gold medal to his wife or his young family. On reflection, Aurelio’s purpose was not primarily to use his gift of a brilliant mind.

His primary life purpose was as a son, brother, husband, father, family member, community member, friend and one of his greatest joys of all-as a grandfather.

Aurelio was greatly loved and admired by his family and friends. Aurelio well fulfilled his life purpose as well as exercising his giftedness.

Aurelio is survived by his wife Norina, their children Joseph, Angella and Louise and their families. The cost of great love is deep grief.

Joseph will become the Managing Director for the group of companies having been in executive management for the company for over 20 years.

– Jim Shooter, NSW State Manager, Pezzimenti Tunnelbore 1994-2019

Sydney Water project wins global award

The project included laying 4.2 km of wastewater pipes and 650 m of stormwater pipes in dense urban areas, connecting more than 200 properties, and the construction of 140 maintenance manholes, as well as repair to vent shafts.

Full completion of this project was achieved in March 2020.

The project was extremely high-impact as a result of the densely populated location, as it affected more than 30,000 customers in Woolloomooloo, Potts Point, and Darlinghurst areas.

The location challenges led the team to adopt advanced technology, such as prefabricated manholes, reducing installation times from 21 days to 3-5 days.

State of the art trenchless construction techniques such as bed bored, stitch boring, and microtunnelling were deployed, reducing noise impacts and minimising the impact on the environment.

The now-improved system can capture and transfer wet weather wastewater overflow in the Woolloomooloo catchment into the Bondi treatment plant.

It has also eliminated wafted odours during the dry weather, which were a main cause of complaint in the community.

The new separated system improves the liveability of the area, minimises the contamination of the Sydney Harbour and Bay, enhances its water quality, and improves marine life.

Sydney Water took an integrated team approach, taking on GHD to lead planning and design, and Diona Civil Engineering for the construction stages.

Pezzimenti and UEA Australia were responsible for the trenchless pipe installation and technology, and Rocla supplied the prefabricated manholes.

For more information visit the Sydney Water website.

MTBM extracted in NZ

Known as ‘Piper’, the MTBM was extracted from 3 m under the seabed using specialist mass flow excavation equipment during a rare weather window in Hokitika, on the west coast of New Zealand’s South Island. 

Piper was then slung under a custom-made pontoon and towed 18 nautical miles (33 km) back to Greymouth.  

McConnell Dowell said the pontoon was designed by the company’s in-house temporary works team and fabricated by its mechanical team. 

The pontoon was also used by McConnell Dowell on the recent Snells Algies Outfall and Army Bay Ocean Outfall projects 

The Westland project involved the construction of 800 m of new trenchless pipeline using the Direct Pipe® system, with the pipeline part of the overall scheme to re-direct waste flows from discharging into the Hokitika River and into a more acceptable location. 

For more information visit the McConnell Dowell website.  

Subsurface engineering solutions leader becomes No-Dig Platinum sponsor

Bothar (part of the Bothar Group of Companies) has built a reputation as the go-to-provider for complex utility tunnelling projects globally. 

Some of the company’s primary capabilities include precision subsea microtunnelling for outfall and intakes, design of complex river crossings, in-house tunnelling equipment manufacturing, pipe manufacturing, shaft construction, auger boring and Direct Pipe® installation, in addition to having its own in-house specialist crane fleet up to 500 t.

Established in Sydney more than three decades ago, the company commenced the execution of high-profile infrastructure projects initially with Bothar-built auger boring machines, and later also with larger Bothar EPB machines.

By early 2000, the company was established across a number of locations throughout Australia and had become one of the most skilled and diverse providers of utility tunnelling solutions in the country.

Building on its strong foundations and home market reputation, Bothar expanded into the Middle East in 2010 to take advantage of the market opportunities in the region.

The company began to offer microtunnelling services as a construction technique and was awarded and successfully completed several high-profile microtunnel sewer and cable projects in Kuwait and the United Arab Emirates. 

Bothar has continued to expand its operational base in the Middle East and is a major player in the region where it has successfully delivered numerous high-profile projects.

In 2015, the company acquired Coleman Microtunnelling to broaden its capability in both scope of operations and geographical spread. This acquisition provided Bothar with further shaft construction experience and immediate access to the wider African market and the European region.

Following a review of potential global opportunities, Bothar opened its first office in Singapore in 2017 and later acquired North America’s leaders in Direct Pipe installation – Innovative Pipeline Crossings Inc. (IPC) in 2018.

Bothar has been, and are involved in, significant microtunnelling projects in the Australasian region, including the first stage of City West Water’s Spencer Street Sewer Main and the North East Link Early Works in Melbourne, Gold Coast Seaway, Cross River Rails – Northern Canopy Tubes, Queens Wharf, the construction of all road and rail crossings on all three CSG 42 inch (1,066 mm) export pipelines in Queensland, and the Hunua 4 Project in Auckland, New Zealand for the Watercare Alliance.

Today, Bothar owns one of the largest fleets of Herrenknecht AG microtunnelling equipment globally with some 42+ machines ranging from 400 mm to 4 m OD and executes projects in diverse locations as the CBD of Melbourne, the desert of Kuwait (+55°C) to near the Arctic Tundra of Northern Canada (-40°C).

For more information visit the Bothar website.

One opportunity left to join industry leaders

One sponsorship opportunity remains for No-Dig Down Under 2021, the Gold tier, which includes sponsorship of the official opening of the exhibition, as well as 36 m2 of premium booth space.

If you’re interested in positioning your company alongside the industry leaders who are already supporting the event, contact Business Development Manager Nick Lovering at

If you have news you would like featured in Trenchless Australasia contact Editor David Convery at

WATCH: MTBM gets ready for launch

The project is being delivered by the Ghella Abergeldie Joint Venture (GAJV) and will comprise nearly 20 km of tunnels, more than 17 shafts, a major pump station and significant wastewater management and network infrastructure works.  

MTBM Domenica will be launched at May Road in Mt Roskill and dig two link sewers that will connect to the main wastewater tunnel totalling 4.2 km. 

The machine has a length of 12 m and a diameter of 2.5-2.8 m. 


The Central Interceptor will run underground from Western Springs, near the Auckland Zoo, to the Māngere Wastewater Treatment Plant.  

The project will result in cleaner waterways for central Auckland and is scheduled for completion in 2025.  

For more information visit the Watercare website.  

Airport opts for underground construction

Sydney Airport is upgrading its Northern Pond Apron Bays 83, 84 and 85 from layover positions to serviced active bays, which will be capable of bussed arrivals and departures.  

To support the operations of active bays, the current infrastructure in these locations required an upgrade for refuelling capabilities, aircraft ground power and preconditioned air.  

To facilitate this refuelling ability, an existing 450 NB fuel feed feedline was extended from its existing termination point to a new junction pit at Bay 83, and Rob Carr was contracted to complete these complex installation works.  

A trenchless solution  

Rob Carr Construction Manager Andrew Scarr said the project included constructing a 523 m long DN900 reinforced concrete jacking pipeline using slurry pressure balanced microtunnelling to install it in three separate drives.  

These drives were carried out predominately through saturated ground conditions consisting of silt, sand and fill.  

To complete the tunnelling and allow for the installation of the 450 NB fuel pipeline within the DN900 concrete pipe, Rob Carr also constructed in situ concrete caissons.  

“The project also included the construction of two 9 m ID caissons and two 4 m ID caissons, which provided a dry and safe working environment for the tunnelling crews to conduct operations,” said Mr Scarr.  

“Caissons were also chosen to minimise dewatering”.  

Mr Scarr said the construction of the second 4 m ID caisson was challenging due to its location, being adjacent to the runway, which required all plant and equipment within the obstacle limitation service; however, at this location it was only 1.4 m above ground level.  

To overcome this challenge, Rob Carr locally lowered the ground level, reduced lift/pour heights on the caisson and only worked while the runway was closed from 11pm-5am and mobilising and demobilising required plant and equipment for each shift.  

Additionally, Mr Scarr said some challenging drilling conditions were encountered with large amounts of foreign material being encountered on the second line.  

“This was able to be dealt with due to the correct selection of microtunnel boring machines (MTBMs), a highly experienced MTBM operator and the perseverance of the MTBM crew enabling the line to be finally completed on line and level.”  

Mr Scarr adds that Rob Carr was also responsible for the management and treatment onsite of assets, the management and disposal of drilling water and the establishment of compounds. 

Working alongside Mr Scarr was Rob Carr Operations Manager Justin Croucamp, with the two men responsible for overseeing the overall construction program and management of the works.  

Additionally, Mr Scarr and Mr Croucamp provided support to both the project’s Project Engineer and Supervisor, being Jamie Leal and Damian Coward respectively.  

“Though the conditions were quite challenging, the project was completed successfully and well ahead of the contract schedule.”  

For more information visit the Rob Carr website. 

This article was featured in the March 2021 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

funding for water business cases

Melbourne Water targets century-old sewer

The Hawthorn Main Sewer transfers sewage from the city’s east to the Western Treatment Plant in Werribee and has been in service for more than a century.  

Now reaching the end of its service life, the brick sewer will be replaced with two glass reinforced plastic pipes, with the project team to construct a shaft on each side of the Yarra and tunnel underneath the river.  

Stage one of the upgrade was the now-completed relining of a 1.7 km stretch from Power Street in Hawthorn to Burnley Street in Richmond.  

Melbourne Water General Manager of Program Delivery Eamonn Kelly said it was crucial the asset continued to function properly.  

“It will provide the community with a world class, secure and reliable sewerage service for the next 100 years,” he said. 

“The Hawthorn Main Sewer has always been an integral part of Melbourne’s critical infrastructure and to this day is one of the principal sewers in Melbourne Water’s 400 km network.” 

The project is targeted for completion in early 2023.  

For more information visit the Melbourne Water website.  

Rob Carr completes complex installation

Rob Carr employed its Iseki slurry pressured balanced machines to install 98 m of 470 OD GRP pipe under Evelyn Street and Fletcher Road in Frankston in record time for FHDB. 

The works were undertaken in water charged and soft silty sand ground conditions that had seen two previous contractors’ efforts to complete the job prove unsuccessful 

In a social media post, Rob Carr said FHDB had entrusted Rob Carr only with the works and both groups had collaborated to ensure the operation was completed successfully. 

“Given the works’ criticality, Rob Carr had one of its most experienced TBM operators on the job Jason Shirtcliffe, who, along with his crew, used every ounce of their experience to ensure the completion of the line,” the company said. 

FHDB is a team of constructors, designers and planners delivering works for South East Water in Victoria. 

Established more than 30 years ago and now a part of Soletanche Bachy, Rob Carr has specialist capabilities in microtunnelling, deep shaft and caisson construction and complex service installations.  

For more information visit the Rob Carr website. 

Edge Underground’s guide to safety

At Edge Underground, safety begins with using the best equipment available – such as the AXIS guided boring system.  

Consideration of safety issues is an integral part of the initial stage of the planning process for any construction project and helps to shape the tendering process.  

Equipment plays a key role in creating this safe worksite, as older machines will not have as many of the in-built safety mechanisms that newer equipment does.  

Edge Underground Managing Director Stuart Harrison said the Edge Underground team uses the best equipment available, including the AXIS guided boring system, as it is equipped with the best operator safety features of all the microtunnelling equipment in the market.  

“It’s designed with a Falling Object Protective System (FPOS) which is a safety enclosure that the operator sits inside, ensuring they aren’t exposed to the outside environment and protected from anything that might fall into the pit from above,” he said.  

“The FPOS is unique to the AXIS – no other microtunnelling machine available has a safety enclosure at all.”  

In addition to the FPOS, the AXIS has several noteworthy internal safety mechanisms to help keep personnel safe while completing the drill, including pressure gauges and strike alert.  

“The pressure gauges, including a vacuum gauge at the rear of the machine, feed information to the operator to notify them of changes in ground pressure,” said Mr Harrison.  

“It’s important to be alerted to these pressure changes as it could signify contact with a trench, which could be housing live wires that weren’t located by Dial Before You Dig (DBYD) services or pre-project geotechnical surveys.”  

The AXIS’ in-built strike alert mechanism alerts the operator if the drill has encountered a power cable and the machine has become live.  

If this occurs, the operator can remain safely within the machine until the power source has been deactivated.  

Mr Harrison says the risks posed by changing in ground pressure are also further mitigated by the AXIS’ ability to retract and complete a pilot line.  

“This allows us to confirm the ground conditions and when we start drilling, any discrepancies that are picked up by the pressure gauges ensures the team can avoid any problems,” he said 

Going trenchless  

Mr Harrison said that specifying a trenchless method of pipeline installation such as microtunnelling in a tender, rather than open cut, can further improve safety outcomes onsite.  

According to Safe Work Australia, excavation work is considered dangerous due to the risk of sudden excavation failures that limit the abilities of workers to escape if a collapse were to occur – with construction work being undertaken in or near shafts or trenches considered particularly high risk. 

This risk increases the deeper the shaft or trench, with those deeper than 1.5 m considered high risk. 

“While some trenchless methods such as microtunnelling and pipe jacking do require excavation of a shaft, the risks are much less than open cut,” said Mr Harrison.  

“Compared to open cut which requires long lengths of trenches to be dug along the length of the pipeline, there is much less excavation needed for the shaft and site supervision is contained to smaller areas.  

“This not only reduces the number of man hours and therefore the incidence of accidents are less, but there is also a reduced risk of public interference.”  

For more information visit 

This article was featured in the March 2021 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.