McConnell Dowell speeds towards project completion in NZ

Microtunnel Boring Machine (MTBM) Hinehōaka completed the boring for the 1,120-m storage pipeline, which includes a marine outfall, late in 2020, with construction taking place in three separate tunnelling drives using pipe-jacking methods.  

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 designed to be capable of retrieving the MTBM from a 3.8-m diameter shaft, 25 m below ground.  

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.  

Once complete, the new marine outfall will reduce overflows and discharge to an outfall far away from places where people swim.   

McConnell Dowell said 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.   

This 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 monitoring meant the team could ensure construction activity operated within the consent conditions and any exceedance was investigated to see what changes could be made to ensure compliance in the immediate future.  

The project is scheduled for completion in 2021. 

For more information visit the McConnell Dowell website.  


Decoding pipe choices for microtunnelling

Contractors and asset managers alike should ask themselves the question – are they selecting or inheriting the right pipe?  

CivilCode Managing Director John Bower can help with the answer.  

Along with founding and managing the software development company CivilCode, Mr Bower is also a consulting engineer and the Principal of Independent Civil Solutions.  

With extensive experience in the industry, Mr Bower offers expert advice for pipe selection that is second to none.  

MDG-S Mr Bower said the recent release of the Microtunnelling Design Guidelines for Sewers (MDG-S) has provided an opportunity to revisit some important design fundamentals.  

Plus, with the increasing capability of methods of installation often involving installation of relatively low stiffness pipe, it has become even more important to understand what strength of pipe is required for the permanent design loads.  

“Whether it is installing a steel pipe under a major highway or a GRP jacking or sleeve pipe in a microtunnel under a railway line, understanding the minimum required strength or stiffness of pipe is fundamental,” said Mr Bower.  

“Over the past few years, I have written a number of papers on this subject, and I was verypleased to have been able to contribute to the MDG-S.”  

The MDG-S explains that most pipes can either be classified as rigid (such as concrete or clay) or flexible (such as PE, PVC, steel, GRP and polypropylene).  

For rigid pipes, the existing design standard provide equations for calculating the relevant permanent design loads for bores or trenchless installations.  

“The only difference between the loads for a conventional (trench or embankment) or a trenchless installation, is how the soil loads are calculated,” said Mr Bower.  

However, in recent times, more and more flexible pipes are being installed using microtunnelling, particularly for sewerage installations.  

“The relevant design standard for structural design of flexible pipes is AS/NZS 2566.1, although this standard does not provide guidance on bored or jacked installations.  

“But, as stated in the MDG-S, the commentary to AS/NZS 2566.1 (Supp. 1) does provide details as to how soil loads can be calculated for “bores”.  

“Other loads can then be determined using the other sections of AS/NZS 2566.1.”  

Mr Bower said, ultimately, the main differences between a trenchless and a conventional trenched installation are how the soil loads should be calculated, what side support can be expected and how the design equations can and should be applied.  

“As explained in the MDG-S, effective grouting of the annulus can be an important part of the design to ensure side support from the native soil can be relied on,” he said 

“Although not included in the MDG-S, it is also possible to carry out a design based on the pipe stiffness alone if the grouting is unlikely to be effective or cannot be completed for some reason.”  

FlxPipe Software  

“If you are thinking that this all sounds a bit complicated, fortunately CivilCode has made it easy for both designers and contractors alike,” said Mr Bower.  

In 2020, CivilCode released a trenchless design option for its FlxPipe design software, being an online application for structural design of buried flexible pipes to AS/NZS 2566.1.  

The new trenchless option allows for the design of both new pipe installations and pipeline renovation.  

With a company-wide aim to produce civil engineering design software to remove the drudgery of manual calculations while retaining transparency at all stages of the process, CivilCode will guide users every step of the way including training on design theory and using FlxPipe 

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.

Rob Carr wins WA sewer contract

The works will allow wastewater to flow from the Ellenbrook, Jandabup and Neerabup main pump stations into the Alkimos Wastewater Treatment Plant as the existing conveyance infrastructure lacks sufficient capacity.

The project involves the installation of 1,931 m of DN1800 sewer main, with 1,167 m to be delivered via microtunnelling, as well as 6 and 25 m deep vortex chambers and 6 more sewer manholes.

Rob Carr said it was looking forward to working closely with its design partner SMEC and Water Corporation to deliver the important infrastructure.

For more information visit the Rob Carr website.

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

An Australian HDD success story

Its proven experience and cooperative knowledge sharing approach is winning many friends across the infrastructure and mining sectors.

The success of Maxibor has been underpinned by building relationships, gaining respect and providing responses. The company sees its cooperative approach as the right model for others to follow, especially in these challenging economic, environmental and social times, saying knowledge sharing is vital to such an approach.

“It is something that has held societies together for untold generations – and it is even more important in these difficult and changing times,” says Maxibor Owner and CEO Rodney O’Meley.

The knowledge sharing concept is embodied in the logo of Indigenous business Native Earthworks, which is one of several Indigenous businesses Maxibor is assisting to better participate in the civil construction sector.

“The symbol of two people sitting together to share knowledge has its origins from societies 12,000 years ago,” says Native Earthworks Owner and proud Torres Strait Islander Chris Young.

“I really like the Maxibor culture of sharing knowledge and cooperating with all stakeholders across the project delivery process. It is certainly helping to make a difference for Native Earthworks.”

In the specialised area of horizontal directional drilling (HDD), it is unlikely the entirety of HDD knowledge will be within asset owners, design engineers or Tier 1 contractors.

“Maxibor is living and breathing HDD at a design, estimation and delivery level each day,” says Mr O’Meley.

“We are more than happy to readily share that knowledge at the right stage of a project so that the best decisions can be made at a concept, design and delivery level for the benefit of all.

“The benefit of Maxibor’s HDD knowledge and, just as importantly, the willingness to share that knowledge, is able to add value at the design, bid and delivery stages of clients’ projects.”

HDD Engineering Special Projects Director Stephen Longeragan is also a strong advocate of HDD being able to solve complex infrastructure project challenges.

“The Maxibor approach is something which the HDD industry needs more of,” he says.

“There are so many benefits to be realised if we all get together early on complex projects to share our HDD knowledge. This will get the right design and therefore provide the optimised delivered outcome.”

Maxibor Senior Project Manager Guy Angus says, “Maxibor’s access to the full suite of HDD knowledge and our cooperative approach in the bid process is helping more and more principal contractor clients to be best positioned in the bid process.”

“They are not only getting a fair and reasonable quoted price but a well thought out design and drilling methodology which fully addresses time, quality, safety, environmental and heritage issues.”

Building relationships

Guy Angus and James Hand developing design and drilling methodology for another HDD project at Maxibor’s new offices at Beresfield, NSW.

Another key driver in Maxibor’s approach is the creation of strategic relationships across the various infrastructure sectors. This requires developing relationships, respect and response at all levels including asset owners, Tier 1s, major contractors, engineering design, suppliers and industry bodies.

Matt Watkins, who has worked on many Tier 1 bids from inside and now consults to the infrastructure sector through Pioneering Consultancy on business strategy, business development and strategic procurement, says “those contractors like Maxibor that are well connected across the whole delivery chain and with wider industry professionals will benefit substantially from that level and style of engagement”.

With bases now established in Queensland, New South Wales and Victoria, Maxibor can mobilise to anywhere in Australia. Its fleet of 12 rigs, including maxi-rigs, mid-rigs, rock drills and other medium drills, means there is no HDD project that Maxibor can’t complete.

Maxibor’s cooperative approach has also seen it develop a close business relationship with HDD provider CT Civil. Based in Victoria and with project experience in NSW and Tasmania, CT Civil’s fleet of three drills includes a Ditch Witch AT40, which is ideal for high strength rock.

“Cooperation with Maxibor is enabling a smaller HDD company like ours to quickly move to another level – the amount of knowledge inside of Maxibor and its well-established network of connections is just amazing,” says CT Civil Managing Director Cam Stevens.

“Our three Ditch Witches and Maxibor’s Vermeer 330×500 and American Auger 660 maxi-rigs plus its two Vermeer 100×120 mid-rigs and five other medium rigs provide a formidable combination with which to provide HDD services in the southern regions of Australia and elsewhere.

“I like what Maxibor is doing on social procurement, especially through the collaborative Indigenous business model. CT Civil was proud to be part of helping Native Earthworks get its website off the ground and is looking forward to utilising their drainage and other civil expertise on the delivery of future infrastructure projects.”

Maxibor National Business Development Manager David Turner says it is important for Maxibor to get the message out there about its knowledge sharing and cooperative approach.

“Being a regular contributor Trenchless Australasia and its sister publication The Australian Pipeliner is all part of that process,” he says.

“The Australasian Trenchless Directory 2020 recently released by the ASTT is an ideal source of information for those involved in the infrastructure sector – it is the who’s who of infrastructure asset owners and suppliers (with Maxibor proudly highlighted on pages 96-97).”

This article was featured in the September 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

For more information visit the Maxibor website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Metro Tunnel hits tunnelling milestone

Metro Tunnel said major construction is continuing in Domain at the site of the future Anzac Station in its most recent tunnelling update report.

In a key milestone for the project, tunnel boring machine (TBM) Alice has now joined TBM Millie on the drive to the CBD after launching from the Anzac Station site in late January,

Metro Tunnel said TBM Alice has already completed 50 m of permanent tunnel, while TBM Millie has completed a total of 650 m.

“Excavation to the concourse level of the station is continuing under the roof slab, whilst on the St Kilda Road side of the acoustic shed, site crews continue digging to base slab level for the tram interchange station entrance,” the update said.

“On the other side of the shed, works have started to build the Shrine of Remembrance entrance back up from the newly constructed base slab level, with columns and internal walls being installed in preparation for roof construction.”

Metro Tunnel also outlined works that will extend beyond February to provide a long-term lookahead, including the ongoing tunnelling of TBM Millie and TBM Alice, excavated soil removal at the tunnelling support site, south box construction, and the construction of Anzac Station entrances at the Shrine of Remembrance and the tram interchange. 

For more information visit the Metro Tunnel website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Tunnelling completed on NZ project

The MTBM has recently been used in the Snells Algies Ocean Outfall project in the North Island, where it had a achieved a new world record of 2,021 m for the longest single drive by a Direct Pipe® MTBM earlier in 2020.

After Snells Algies Ocean Outfall, the MTBM was quickly re-mobilised at the Westland Milk Products project.

McConnell Dowell said its project team used its world leading experience to complete the 845 m of tunnelling and install the 832 m steel outer casing for the wastewater pipeline in just over one month, two weeks ahead of the expected constructed program.

“The Direct Pipe tunnelling method was chosen to mitigate the impact of work on the delicate coastal ecosystem,” the company said.

The scope of works included constructing a 60 m long, 6 m wide and 7.5 m deep sheet piled MTBM launch trench; completing the 845 m micro tunnel Direct Pipe drive; installing 832 m of steel casing pipe through the Direct Pipe thrusting technique that remains buried and submerged at the seaward end; and sliplining installation of the HDPE carrier pipeline into the steel casing pipe.

McConnell Dowell said an ocean recovery of the MTBM followed by installation of the marine diffuser will also be required, as was construction of an onshore deaeration chamber and carrier pipe connection.

“To retrieve Piper the MTBM, specialist excavation equipment sourced from Malaysia will be used to expose Piper under the seabed,” the company said.

“A dive team will then disconnect Piper and tow her to Greymouth Port where she will be lifted from the water. 

“Once complete, this project will be the first ocean outfall on the west coast of the South Island and will provide a new ocean discharge point for the treated wastewater from the Westland Milk Products facility.”

The company expects final marine operations will be completed early this year.

For more information visit the McConnell Dowell website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

A leading BRANDT for HDD solutions

As market leaders in oil and gas, National Oilwell Varco (NOV) has been manufacturing shakers and centrifuges, its flagship products, for more than five decades – longer than many companies have even been in operation.

With 70 per cent worldwide offshore market share in conventional oil and gas field supplies, NOV Regional Sales Manager for the Far East Alec Cochrane says its equipment and services easily translate to the horizontal directional drilling (HDD) and microtunnelling industry and has for some time.

Intersected technologies

“We’ve actually always been involved in the HDD industry, more so in Europe,” says Mr Cochrane.

“For the past 15 years, we’ve been involved in supplying equipment mainly to rig builders like Herrenknecht, and also offering our equipment as a complete service by renting our equipment and supplying operating personnel.”

NOV’s experience in the oil and gas sectors carries through to the trenchless industry and Mr Cochrane says the equipment, technology and methodology are often intertwined.

“Equipment we provide to oil and gas can be transferred into HDD and is a really good fit because the HDD companies face the same challenges that the oil and gas companies face, just in a different environment.

“Instead of being offshore, you are onshore somewhere and, sometimes, it can be really remote. So, it’s very important that the equipment is reliable and that it doesn’t break down, which can cause financial penalties to our customers.”

COE Drilling continues to operate a wide range of machinery and equipment, manufactured and supplied by NOV.


NOV’s industrial segment, BRANDT Industrial Technologies, focuses on the equipment trenchless companies need to separate drilling solids by designing, manufacturing and selling its renowned BRANDT solids control and waste management products and services.

Mr Cochrane says the company is an enabler of technologies for the industry by offering high performance equipment to save operators time and money, improve overall drilling performance and lower its customers’ bottom lines by efficiently separating solids.

“By focusing on the performance of the equipment and getting the best out of the equipment from the design, [our equipment] can process more fluid volume and we can process it more efficiently, which means we can save the customers money on their fluid and waste disposal bill,” says Mr Cochrane.

“We are trying to reduce the amount of waste generated and reduce the amount of fluid wasted by helping reclaim drilling fluids for re-use.”

The company manufactures and supplies high performance equipment that can process faster, more efficiently and down to a much finer spec with regards to cut point than competing machinery.

Mr Cochrane says although some HDD companies in Australia may not have heard of BRANDT, its long-term involvement in the drilling industry makes it one of the most experienced manufacturers in the field.

Comprehensive service

NOV retains its position as an industry pioneer by not solely being a manufacturer of BRANDT equipment, but also supplying and renting the equipment and providing experienced personnel.

“We provide a service, we don’t just sell,” says Mr Cochrane.

“We can also rent the equipment and we can provide competent people to optimise the equipment, which ultimately means they will drill faster.”

Long-term customer COE Drilling can attest to this comprehensive service, with COE Drilling Operations Manager David Newitt saying its projects are always planned to use the correct equipment and personnel.

“With this we engage NOV trained personnel to operate and run our mud systems,” says Mr Newitt.

“We have found this works very well as we have the support of NOV with their personnel knowing the equipment and have been able to get direct information on any issue that may arise.”

Mr Newitt adds that NOV’s vast knowledge of the work, not only in running and renting the systems, but also designing and building mud systems, pumps, shakers and more is reassuring.

“Knowing we can pick up the phone and have access to an abundance of support from NOV is priceless.

“Dealing with them onsite or over the phone is also easy; you know that if you have any issue and you need advice, support or parts, NOV will do their utmost to help you.”

NOV has also supplied machinery to Australian HDD specialist HDI Lucas, with transactions dating back a whole decade; HDI Lucas is still using the equipment on NOV’s rigs today, posting on social media that the VSM300 Shaker was “running well” while taking a cut on the pipe-side of a project.

This long-term, ongoing relationship demonstrates not only NOV’s commitment to its customers, but the incomparable quality of its design and manufacturing process. Among its global network of sales, service, manufacturing, distribution and waste treatment facilities, NOV has operations across both the western and eastern coasts of Australia.

This article was featured in the September 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

For more information visit the National Oilwell Varco website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

View the latest trenchless technology tenders

View the latest trenchless technology tenders

Sydney Metro Western Sydney Airport – Advanced and Enabling Works (AEW)
Issued by: Sydney Metro (NSW Government)
Closing date: 22 January 2021
Location: New South Wales
Description: Sydney Metro advises that an upcoming invitation for registrations of interest associated with the installation and commissioning of construction power, construction water and stormwater diversions for the Sydney Metro Western Sydney Airport project is scheduled to be advertised on or around 22 January 2021. It is expected the works will include construction water supply and stormwater diversion.

Cross River Rail – Tunnel and Stations – Directional Drilling Contractors
Issued by:
Cross River Rail Delivery Authority
Closing date:
31 March 2021
: Expression of interest is sought from directional drilling contractors for utilities relocation packages, under boring works for various potential packages of work.

Nyngan Water Supply-Off River Storage 1B
Issued by:
Public Works Advisory (NSW Government)
Closing date:
19 January 2021
New South Wales
: The works under this contract consists of supply of all materials, plant, equipment and labour and construction of an in-ground storage including spillway and drainage, road access, and pipework.

McAlister Street Watermain Renewal
Issued by: Whakatane District Council
Closing date: 29 January 2021
Location: New Zealand
Description: Tenders are invited from suitably qualified contractors for the works as described in the document. Below is the summary of the scope for this contract:

  • Supply and installation of approximately 630m of DN280 PE100 SDR11 pipework.
  • Supply and installation of approximately 70m of DN200 Ductile Iron PN20 (or SS316 SCH10) pipework.
  • Supply and installation of approximately 210m of DN180 PE100 SDR11 pipework.
  • Supply and installation of approximately 230m of DN125 PE100 SDR11 pipework.
  • Supply and installation of short lengths of DN63 PE100 SDR11 pipework.
  • Construction of pipework connections (tee’s, bends, valves, hydrants, thrust blocks).
  • Construction of approximately 50 property connections.
  • Pressure testing, flushing, chlorination, and commissioning of works.
  • Decommissioning of existing valves, hydrants, and property connections.

Construction and Rehabilitation of Transport and Drainage Infrastructure
Issued by:
Brisbane City Council
Closing date:
3 March 2021
Description: Council is seeking proposals for the establishment of a corporate procurement arrangement for the construction and rehabilitation of transport and drainage infrastructure.

Buchan Water Treatment Plant Raw Water Storage
Issued by:
East Gippsland Water
Closing date:
12 February 2021
This tender is for the supply and installation of a new raw water storage tank including a new raw water pump station at the Buchan Water Treatment Plant. Tender documentation will be available for collection by arrangement from East Gippsland Water’s office at 133 Macleod Street, Bairnsdale (telephone 1300 720 700), on USB memory stick ($12.00 fee applies per tender document) or hard copy ($35.00 fee applies per tender document). This project is being funded as part of the Victorian Government’s $2.7 billion Building Works stimulus package.

Herdsman Main Drain to Perry Lakes Drainage Diversion Project (Design and Construction)
Issued by:
Town of Cambridge
Closing date:
27 January 2021
Western Australia
The town is seeking a suitably qualified and experienced Contractor to undertake the design and construction of the Herdsman Main Drain to Perry Lakes Drainage Diversion Project as stated in RFT 2021-02.

Each fortnight, the Trenchless Australasia e-newsletter includes a list of tenders relevant to no-dig contractors, suppliers and manufacturers.

The information is provided by Australian Tenders, which is renowned for being an Australia-wide locally owned and operated tender notification service.

Australian Tenders is also offering readers of Trenchless Australasia three months free on their subscription plans.

Email for more information.

For more tender information visit the Australian Tenders website.

If you have a tender you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

D.J. Mac Cormick completes Townsville microtunnel

As part of the Water Security Infrastructure – Stage I Project for the Haughton Pipeline Duplication, the City of Townsville required a pipe installation comprising of 35.6 km of DN1800 GRP pipeline.

The pipeline alignment included microtunnelling under the Flinders Highway and between rail lines and rail corridors, requiring a 2.5 m outside diameter enveloper pipe to be installed 120 m in length by pipejacking.

To undertake the project, D.J. Mac Cormick Contractors selected one of its Herrenknecht tunnelling systems with a mixed cutting wheel, which was chosen as ground conditions ranged from stiff sand and clay to granodiorite rock.

Launch pit design. Image courtesy of DJ Mac Cormick Contractors.

A detailed temporary design was completed for the launch shaft shoring, thrust block, concrete pad, entrance wall and receival shaft for tunnel boring machine removal, while the chosen jacking system is capable of up to an 850 t safe jacking load.

The DN1800 GRP carrier pipe was installed inside the 2.1 m, 12.2 t jacking pipe – supplied by Humes – following the grouting of annulus outside of pipe.

Using trenchless construction, the pipe was installed in 11 days, with a total tunnelling drive length of 120 m.

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

This article was originally published on 31 March 2020.

If you have project news you would like featured in Trenchless Australasia contact Head of Production Chloe Jenkins at

McConnell Dowell sets world record

McConnell Dowell completed the drive on Watercare’s Snells Algies wastewater pipe and outfall project with the MTBM setting a record of 2021 m, surpassing the previous mark set in New Zealand by record 92 m.

The Herrenknecht machine bored through challenging geology and a curved alignment to complete its work during the COVID-19 lockdown after being deemed an “essential” project.

McConnell Dowell Project Manager Brent Whiting says the record achievement demonstrates the depth and skill of experience in the company’s tunnelling teams and its dedication to working through challenges.

After its breakthrough, the MTBM was driven into a trench off the coast of Martins Bay where it will be separated, lifted and transported to a local harbour.

The project is the first phase of Watercare’s three-stage scheme to supply the surrounding communities with reliable wastewater services.

For more information visit the McConnell Dowell website.

This article was originally published on 5 August 2020.

If you have news you would like featured in Trenchless Australasia Assistant Editor Sophie Venz at

McConnell Dowell sets another record

McConnell Dowell said its AVN2500 MTBM has once again set a new pipe-jacking record for the longest single drive in the southern hemisphere by a TBM greater than 2.6 m in diameter.

The project recorded 1,216 m upon completion of the second drive for its pipeline earlier in the year, before breaking that marker with a 1,296 m drive on 20 November 2020.

Hunua 4, Section 11 Project Manager Richard Atkin said he could not have asked for a more experience tunnelling team to successfully navigate through Auckland’s challenging volcanic fields, which comprise of hard basalt up to 160 MPa.

“To gain another record for this project after 18 months of tunnelling, across three individual drives, has put the team in good spirits as we near the finish line,” said Mr Atkin.

The record is a hard-earned achievement while the team delivers the 3.5 km watermain upgrade for Watercare.

The project’s record-breaking drive consisted mostly of basalt rock and tough clay ground condition, which the crew worked through to complete the final drive in less than three months.

McConnell Dowell Tunnelling and Underground Group Technical Director Justin Shepherd has praised the project efforts.

“McConnell Dowell challenges both the norm and ourselves by thinking creatively, engaging our multi-discipline specialists, embracing new technology, and driving continuous improvement through our teams and projects,” said Mr Shepherd.

“This project, which we believe to be the longest large diameter pipe-jacked drive through ‘continuous hard-rock conditions’ in the world, exemplifies McConnell Dowell’s approach to successfully delivering award-winning, and record-breaking, tunnelling and underground work.”

The next step for the project team is the installation of the 1,575 mm diameter concrete-lined steel watermain pipes inside the tunnel, planned for early 2021.

For more information visit the McConnell Dowell website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Lonsdale Street Sewer Upgrade complete

The Lonsdale Street Sewer Upgrade is the second stage of City West Water’s (CWW) four-stage $80 million program to expand Melbourne CBD’s sewer system capacity, with the new pipe linking to a new sewer under Spencer Street that was installed as part of stage one in December 2018.

Contractor Rob Carr installed the new 1.5 m diameter sewer pipe under Lonsdale Street using a 6.3 m, 16.3 t microtunnel boring machine (MTBM), which worked at depths ranging between 10 and 23 m.

The MTBM had tunnelled 24 hours a day from March to September this year and encountered a variety of hard and soft ground conditions throughout.

To support tunnelling activity, a 23 m deep launch shaft was excavated at William Street as well as two 10 m deep retrieval shafts at Elizabeth Street and Spencer Street.

Each of the three shafts have now been filled in, closed and replaced with manholes.  

CWW Managing Director Maree Lang said the new pipe formed part of the biggest upgrade to Melbourne CBD’s sewer network in more than 120 years.

“With the existing sewer over 120 years old, the new sewer pipe will help cater for the growing demands of the Melbourne CBD now and into the future,” she said.   

“We sincerely thank the thousands of city residents, workers and commuters who adapted to the changed conditions while we carried out construction along Lonsdale Street.

“Your patience and understanding allowed us to provide this vital piece of infrastructure for Melbourne’s CBD.” 

The next phase of works will include a new sewer along Elizbeth Street, with construction expected to begin in mid-2021.

For more information visit the CWW website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Cross River Rail TBM ready for transport

The Cross River Rail will connect the northern and southern rail networks in Brisbane’s CBD via a 10.2 km line from Dutton Park to Bowen Hills, with 5.9 km of the alignment being tunnelled under Brisbane River.

The two TBMs are currently being built at Herrenknecht’s northside facility where the first machine is undergoing final checks before it will be dissembled and transported to Cross River Rail’s Woolloongabba site.

The second TBM is expected to arrive onsite by early 2021, at which point crews will launch both machines to begin tunnelling by the middle of the year.

The TBMs are both 164 m long, with cutterheads weighing 106 t and measuring 7.2 m in diameter.

While tunnelling, the TBMs will also install 4.2 t precast concrete segments to line the tunnel and will work at a rate of 20-30 m per day.

The Cross River Rail project will deliver four new underground stations at Boggo Road, Woolloongabba, Albert Street and Roma Street, as well as upgrades to eight above ground stations at Salisbury, Rocklea, Moorooka, Yeerongpilly, Yeronga, Fairfield, Dutton Park and Exhibition.

Three new stations on the Gold Coast line at Pimpama, Helensvale North and Merrimac will also be constructed.

The project is expected to be operational in 2024.

For more information visit the Cross River Rail website.

If you have project news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Pezzimenti Tunnelbore completes rail works

Pezzimenti Tunnelbore shared images of the project on social media, saying the completion had “exceeded expectations”.

The team had five days to complete the works, including the initial site establishment and the re-instatement of work areas upon work completion.

Over the shutdown period, the team successfully undertook vacuum extraction microtunnelling, the installation and removal of 32 m of DN540 mild steel casing and the installation of 32 m of DN400 RCP Class 4 jacking pipe.

Pezzimenti Tunnelbore said despite the five-day shutdown, the project was delivered on an accelerated program.

For more information visit the Pezzimenti Tunnelbore website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Major project requires Adept solution

The six-month project was awarded in April 2020, with the sole contractor – Adept Civil Group – having to work through tough lockdown conditions in Victoria during the COVID-19 pandemic. 

At the beginning of October, Adept announced the project’s completion, saying the entire team came together to reach the milestone on what was a major infrastructure upgrade contract. 

The works comprised a microtunnelled rock bore under the Geelong to Melbourne V/Line VicTrack Rail Line and Armstrong Road at Windermere, which allowed for a new power feed. To carry out the microtunnelling, Adept excavated both launch and retrieval shafts at approximately 10 m deep in solid basalt rock. 

The 10 m deep launch shaft.

The rock bore then consisted of 105 m pipe jacking of a 427 mm GRP sleeve for the installation of two 180 mm and one 125 mm PE power conduits. To complete the bore, Adept used and supplied the Vermeer Axis Micro Tunnelling Machine. 

Adept says constant support of the bore was necessary during the project, including while piloting the 350 mm diameter tri cone head, jacking the 427 mm GRP pipe and backreaming with a 440 mm diameter rock head. 

“The Axis machine was chosen for this project due to the crucial scope of having a fully supported bore at all times under the rail,” the company says. 

“Our microtunnelling machine and our companies unique advanced technology was the reason we were selected by all stakeholders to carry out these critical works.” 

While the team kept busy on the Windermere Railway Services Crossing project and numerous other jobs across Victoria during the COVID-19 pandemic, Managing Director Anthony Panozzo said he “couldn’t be prouder”. 

“With a high level of global uncertainty at the moment, the fabric of our team is showing,” says Mr Panozzo. 

“Our objective is to get through these difficult times together and come through the other side of this united as one and hopefully all stronger.”

A committed team

While working through COVID-19 restrictions, many companies have strengthened their approach to safety. For Adept, safety has always been an absolute priority. 

Renowned for its 100 per cent commitment to safety, Adept ensures its in-house training and careful site management keeps it on track for its goal of zero workplace injuries. 

“We achieve this by giving our employees a safe workplace, complying with health and safety legislation and making sure our employees know the details of our health and safety policy,” says Adept. 

The company also holds numerous Quality and OHS Certifications, provides clear work instructions and procedures for each project and then audits its projects to ensure the team complies with health and safety legislation. 

Along with its commitment to safety, the Adept team also works with the organisational philosophy of environmental management by consistent education, communication and improvement. 

“By embracing these principles, we aim to minimise pollution created during any works process and continually monitor our impacts on the environment through ongoing reports, audits and inspections,” says Adept.

This article was featured in the December 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

For more information visit the Adept Civil Group website.

If you have news you would like featured in Trenchless Australasia contact Journalist Sophie Venz at

Successful microtunnelling breakthrough in NZ

March Construction Business Development Manager Edward Rushe said the breakthrough marked “great work” by the team.

The team has been working with Rob Carr on the project, which is located in Ponsonby, NZ, near Auckland.

March Construction is a subsidiary of Soletanche Bachy and has more than 40 years of operational experience across NZ.

Conversely, Rob Carr has operations primarily across Australia, although it works as both a head contractor and sub-contractor on diverse projects across the entire Australasian region. 

For more information visit the March Construction website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Rob Carr wins excellence award

Sharing the news on social media, Rob Carr congratulated its team, led by Barry Crowley and Paul Lee, which won the award in the $5-10 million project value category.

“The team recently delivered the very successful Dunsborough Infill Sewerage Project Sections 5C & 9A,” said Rob Carr.

The Dunsborough Infill Sewerage Project.

The project was part of Water Corporation’s Infill Sewerage Program and consisted of more than 5.2 km of gravity sewer constructed by microtunnelling and conventional techniques.

Rob Carr also completed 36 access chambers, 41 maintenance shafts, 215 property connections, 1.5 km of pressure main pipelines by horizontal directional drilling and two Type 40 pump stations.

The company said it completed all works while minimising impact to the local community, environment and conservation areas.

“Another example of Rob Carr delivering project excellence for its clients.”

For more information visit the Rob Carr website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Construction to return

WATCH: Adept microtunnelling success

In a social media post, Adept Civil Group shared the video and said it is “extremely proud to be able to share with you what an amazing machine [is] capable of achieving”.

“Being one of a few companies around the world that is fortunate to be able to deliver complex microtunnelling projects for our clients and partners with our Axis is humbling,” Adept says.

“We are very proud with the work we did with Vermeer Corporation and RDO Equipment Australia in making this happen.”

Vermeer says its Axis Guided Microtunnelling Machine is a pit-launched boring system designed to achieve pinpoint, on-grade accuracy and can meet a wide range of product pipe, sizing specifications and other jobsite requirements.

For more information visit the Adept Civil Group website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Webinar puts microtunnelling on the agenda

Titled Unpacking the ASTT Microtunnelling Design Guidelines for Sewers, presenters Jim Shooter, Robert Loncar and John Bower examined how the microtunnelling design guidelines for sewers were created, with the three basic microtunnelling sections and how the design for each differs.

The webinar also covered the role of geotechnical information and the difference between designing a rigid and a flexible pipe.

“No matter where you go, you’re going to hear that the geotechnical information is critical,” said Mr Shooter.

“To work with the ground, you’ve got to know what it is. The amount of preparation required for trenchless is enormous compared to open cut work.

“There are many geotechnical methods that are now available, and they have progressed enormously over the years.”

The ASTT has been holding webinars in place of its in-person trenchless forums this year due to restrictions on gathering brought about by the COVID-19 pandemic.

For more information on the society or upcoming webinars visit the ASTT website.

If you have an event you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Ticking every box

The company has completed countless underground infrastructure projects throughout New Zealand, often using its own custom-made trenchless tools to ensure elite performance.

Pipeline and Civil attributes its success to both its outstanding project expertise as well as its strong company culture of collaboration and inclusiveness. The company places a significant emphasis on the values of safety, quality, honesty, care and success when delivering each project and takes great pride in delivering results for clients on time, on budget and with a low impact on the surrounding community.

Pipeline and Civils’ custom built telescopic conveyor can be used for backfilling trenches from the end where access is not possible to backfill from the side of the trench. This is particularly relevant in constrained urban areas where local authorities demand that traffic lanes remain open, reducing lateral safety zones and preventing equipment from accessing the side of the trench.

Although it can now claim expertise in many areas, Pipeline and Civil was originally founded on its ability to deliver high quality water infrastructure. The company has constructed some of New Zealand’s largest water mains and has the capability to undertake many different construction and rehabilitation works, including installing high-density polyethylene rising mains, pump stations and associated pipe works, water treatment plants and storage tanks.

Pipeline and Civil sees immense value in using trenchless technology due to its environmental, practical and cost benefits, with the company saying most of its projects now use at least one trenchless method.

Pipeline and Civil is an expert in slip lining, having installed pipe strings up to 400 m in length and 1,400 mm in diameter, while its horizontal directional drilling (HDD) knowledge is also top level and its in-house welding team ensures only the highest quality welds are performed on a project. Pipeline and Civil also boasts expertise in pipe bursting, pipe ramming, microtunnelling and structural lining – the result of many years of experience across its teams and its involvement in some of NZ’s largest and most complex trenchless projects.

Additionally, the company has strong relationships with subcontractors that are experts in these methodologies, ensuring clients have the sharpest minds in the business on hand for their works.

 The image above shows work in progress on a 7 km of 710 OD PE pressure wastewater pipe in northwest Auckland.

Custom linear winch

In addition to its project expertise, the company’s leading technical and engineering knowledge has allowed it to develop its own custom-made tools to use onsite. Recently, a project with Hastings District Council and Stantec provided the opportunity to use a custom hydraulic winch, designed and built by Pipeline and Civil.

The hydraulic linear winch was developed for the specific purpose of pulling polyethylene (PE) pipe through a host pipe and can be adjusted to suit different sized pipes. Capable of pipe pulls up to 400 m in length and applying up to 45 t of force to overcome internal friction, the winch has now been successfully tried and tested across five projects by Pipeline and Civil.

The works included the installation of 1,460 m of DN355 PE pipe that was relined, using the hydraulic winch, through the existing 375 concrete pipe, which was very deteriorated in places and had recently required several repairs. To properly rehabilitate the asset, relining had been chosen as the optimal solution.

Relining an existing host pipe greatly extends the life span of the pipe and in this case also allows it to withstand more pressure and more flow. The Pipeline and Civil team also shut down three pump stations and installed three new valve connections and two 90° bends over the 1.5 km stretch.

The upgrade will allow the sewage system to operate with more efficiency at full capacity and the overall project was completed in just under 10 weeks.

This article was featured in the September 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

For more information visit the Pipeline and Civil website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Forward HDD thinking for positive outcomes

Watercare’s Northern Interceptor project, using a specialist HDD solution by HDI Lucas, demonstrates how advanced planning combined with trenchless technology can deliver results in highly populated areas, while minimising impacts to community and environment.

Auckland is New Zealand’s economic powerhouse, located in the North Island with a population of 1.7 million. The city is undergoing rapid growth and is seeing major infrastructure investment, including the Northern Interceptor wastewater project. With a new wastewater pipe designed to redirect flows from the northwest areas of the city to the Rosedale Wastewater Treatment Plant in Albany, the Northern Interceptor will be completed in stages as population increases. The first phase will involve combining construction work with a new watermain across the Upper Waitematã Harbour.

As a council-controlled organisation, Watercare provides water and wastewater services to the people of Auckland and Project Manager Dave Moore says forward thinking was vital in relation to planning major infrastructure such as Northern Interceptor.

“Forecasting shows that Auckland’s population is set to increase by 700,000 people in the next 30 years, and our networks need to be prepared well in advance to continue to provide reliable, safe and efficient services,” he says.

“Commencing major projects like Northern Interceptor in advance of demand ensures we are able to plan and manage the project effectively, consulting with local iwi and our wider communities and prioritising sustainability. It also really exemplifies that we are living Watercare’s vision: “Better tomorrow than we are today – Pai ake apõpõ atu i tenei rã.”

Workers onsite overseeing the pipe pulling operations.

Clear objectives, but many considerations

While project objectives were clear, the best way to achieve them was less obvious. Project location presented limited existing infrastructure options and major obstacles, with waterside position meaning access to North Auckland was only available via two options: a marine trench or a trenchless solution across the Upper Waitematã Harbour.

Along with all areas in the vicinity of the pipeline being either densely populated urban environments or pristine waterways, identification of a suitable pipeline path and construction methods were key to optimising outcomes. Principal contractor Fletcher Construction recognised the benefits of incorporating horizontal directional drilling (HDD) into the project at the design stage, engaging HDI Lucas to provide specialised trenchless engineering and construction.

HDI Lucas General Manager John Stuart-Robertson says the challenge was to design the large-scale pipeline and associated installation methods, balancing functional requirements with environmental and stakeholder impacts, engineering constraints and cost.

“We knew what infrastructure was required to be connected by the pipeline, but there were a range of options for what path the pipeline would take, and how it would be installed, as well as significant obstacles – the most obvious being the Upper Waitematã Harbour,” he says.

After exploring several options, a final pipeline design was decided upon, incorporating 500 mm HDPE PN 16 sewage rising mains under the Upper Waitematã Harbour and Te Wharau Creek.

HDD solution in complex circumstances Mr Stuart-Robertson says the incorporation of HDD opened major efficiencies and benefits for the pipeline.

“Fletcher Construction had options to construct the pipeline without using HDD, but marine trenching was not the preferred option in the Watercare tender, as it meant potentially a much longer path around the harbour and a lot more impact on the community and environment via trenching along roads and other properties,” he says.

“By using HDD, the pipeline was able to take a much more direct and optimal path, passing directly underneath the harbour and coastal creek, avoiding excessive disruption of highly populated areas and a key transport waterway.”

Mr Stuart-Robertson says the project presented several engineering difficulties that were overcome by effective planning and preparation.

“We completed the maxi rig HDD crossings in challenging rock and clay conditions, and detailed planning and preparation was required to ensure the crossings were constructible and risk was as low as possible,” he says.

“We engineered the crossings to be completed at maximum depth and drillable angles to prevent hydrofracture, without any risky compound curves. Additionally, our bottom hole assemblies were manufactured with variable jet configurations to overcome the East Coast Bays Waitematã rock and sticky clay.

“We also needed to complete detailed planning and negotiation to secure a suitable stringing area, as the urban location of the pipeline meant that options large enough to be safe and suitable were severely limited.”

Wide project benefits, both short and long term

HDI Lucas’ HDD rig at the Northern Interceptor project.

Mr Stuart-Robertson added that advanced planning and use of HDD for the project also allowed for effective prioritisation of the culturally significant waterways and wider environments.

“As well as being ecologically and environmentally significant, detailed archaeological assessment carried out for the project showed that the banks of Te Wharau Creek were a significant ancient Mãori burial ground,” he says.

“By using trenchless methods, those culturally important areas remained untouched and unaffected by the project. This is just one example of how use of HDD, along with effective planning, allowed the project to be completed with great regard and respect for the environment and local communities and stakeholders, maximising project support and positive outcomes.”

Fletcher Construction Project Manager Mike Wall says the project brought benefits to the community on both an initial and ongoing basis.

“Local crews were employed in every aspect of construction, bringing new jobs to New Zealanders,” he says.

“But the real benefits of Northern Interceptor will be felt in the future. Communities in north Auckland will benefit directly from additional wastewater capacity of the Rosedale plant, and the strain will also be taken off the Mãngere plant, optimising its lifespan and minimising the need for works in surrounding areas.”

With the overall stage one of the project nearing completion, additional stages will be completed based on population growth.

This article was featured in the September 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

For more information visit the HDI Lucas website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Creative collaboration beats challenging conditions

The Gold Coast, Queensland, offers a wide-ranging appeal to locals and tourists alike, demonstrated through its influx of visitors all year round and steadily increasing local population. Recognising this growth, the City of Gold Coast has taken a proactive approach in upgrading its civil infrastructure to ensure the city remains both liveable and a popular tourist destination.

Isle of Capri Bridge Project

The Isle of Capri Bridge Project is indicative of this desire, comprising the construction of a new four-lane bridge, along with road and intersection upgrades and the relocation of underground services including the sewer rising mains.

Serving as a major connection between the east and west areas of the coast, the project aims to minimise congestion and increase network capacity while avoiding disruption to more than 18,000 vehicles and users traversing the area daily.

As a vital aspect of the project, Pipeline Drillers Group was engaged by the City of Gold Coast to construct the sewer rising mains aspect of the project utilising trenchless methodology, including more than 500 m of horizontal directional drilling (HDD) of high-density polyethylene sewer lines and crossing the Nerang River.

The use of HDD allowed the project’s proponents to avoid short-term options like attaching services to the old bridge, and the limited capacity and life that these types of solutions present.

A challenging task

Pipeline Drillers Group Director John Whitbread says the challenges of the project were evident from the very start.

“If the Gold Coast looks busy on the surface, the same can be said for underground,” he says.

“We had our work cut out for us, with the large quantity and density of existing services; very small entry and exit work areas adjacent to the Gold Coast Highway, combined with the need for a maxi size HDD rig; and the need to maintain suitable depth of cover under the Nerang River and near the neighbouring tidal wall. And we needed to do this while minimising disruption to users of the area, as well as locals neighbouring the construction sites, all in dense sand conditions.”

However, there were significant advantages throughout the project as well, with Mr Whitbread saying the City of Gold Coast – as the client – demonstrated it had a great understanding of the project constraints as well as a creative and innovative attitude.

“This provided the perfect platform to work together really effectively, incorporating constraints and minimising risk, while coming to a really clever, modern HDD solution,” he says.

“We still knew that with the right design, risk mitigation, and correct tooling and equipment, the job was achievable.”

Conventional is not the key

Due to the existing services, obstacles and space constraints under the waterway, a conventional HDD design was not feasible.

“Knowing this from the start, we engaged our preferred HDD designer, Future-Proof Solutions, to review and improve the client’s design undertaken by SMEC. Together we were able to plan and conceive an innovative solution,” says Mr Whitbread.

The first issue faced was the limited depth of cover at entry, where a hydrofracture analysis showed the initially designed profile area was a high risk for drilling fluid release and bore hole collapse.

Mr Whitbread says to mitigate drilling construction risks, a hammering technique was used to install the sacrificial conductor pipe that minimised the disturbance to the sand conditions and stabilised the surface area of the bore hole prior to the commencement of HDD operations.

The next major hurdle was the excess of the existing services – including other HDD crossings – in the section under the river.

“We had to avoid the services, but we couldn’t risk introducing a compound curve, with their potential for doglegs, tooling snap-off and other HDD nightmares,” says Mr Whitbread.

“So, we worked with Future-Proof Solutions to conceive an innovative solution incorporating a combined radius for the section under the Nerang River, with the profile curving horizontally and vertically in the same section, with the same tangent points.

“With the modified design, and our construction experience and expertise, we were able to drill a much more consistent profile, steer pattern and borehole, with limited directional changes and the problems they introduce.”

However, the challenges continued once the profile had crossed the waterway, as the project partners still needed to target a suitable exit location while avoiding more existing services. To do so, a horizontal radius was incorporated into the 12° exit section, allowing a successful execution of this section of the hole and a punch out in the tight exit area as had been planned.

A community collaboration

Mr Whitbread says the project was supported by both internal cooperation and the wider Gold Coast community.

“The City of Gold Coast construction teams were sensible and committed to good outcomes for their communities,” he says.

“Their commitment to community engagement was sincere, and due to these efforts, the community was understanding and supportive of what we needed to do during HDD.”

Throughout the HDD project, the Pipeline Drillers Group team provided construction advice to guide the City of Gold Coast to a positive outcome.

“We delivered the project on time and on budget, allowing the larger Isle of Capri Bridge Project to progress without impact. It was a phenomenal success, especially considering the difficulties we had to overcome,” says Mr Whitbread.

“This project had so much going on that we really had to be creative. But this was only possible with the trust and collaboration of the City of Gold Coast. They let us do our job, thinking outside the box, and without that cooperation and innovative attitude from both contractor and client, there’s no way we could have achieved the great outcome that we did.”

This article was featured in the September 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.

For more information visit the Pipeline Drillers Group website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

Rob Carr project named award finalist

Held each year, Engineers Australia’s Australian Engineering Excellence Awards showcase achievements in the industry that exhibit excellence, distinction, merit and quality as well as inspiring and encouraging these qualities through teamwork and innovation.

Named as a finalist for 2020, Rob Carr said its Green Square Stormwater Drain project represents an outstanding achievement in engineering and demonstrates the invaluable contribution engineering makes to the economy, community and the environment.

Delivered by the Drying Green Alliance, Rob Carr was subcontracted to deliver a new 2 km stormwater drain to reduce hazardous flooding in and around the Green Square area.

In the project delivery, Rob Carr microtunnelled nearly 4 km of DN1800 concrete jacking pipe, construction five caissons, constructed complex civil structures within these caissons and completed eight convention shored shafts.

As Green Square is located on a floodplain, Rob Carr had to work through extremely difficult conditions, including working in a high water table ground classified as restricted and hazardous.

The team also had to contend with sites full of buried industrial waste that would repeatedly stall works, increase program demands and add to the constrained project site pressures.

The winner of the award will be announced during virtual award ceremonies across each Engineers Australia Division commencing Monday 14 September. 

For more information visit the Rob Carr website.

If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at

WATCH: MTBM breaks through

The challenging bore was part of the M205 Carlton Water Main Renewal project, with the MTBM breaking through to the other side of the Pigdon Street roundabout on Canning Street, Carlton North.

Edge Underground was required to complete the bore without interfering with or damaging the complex underground infrastructure network and said the site’s ground conditions – a complicated mix of rock and clay with a small section of previously excavated ground – also provided an interesting challenge for its team.

“However, with the team’s expertise and using the AXIS laser guided microtunnelling system, the bore was a success,” said Edge Underground.  

City West Water said the complex network and the presence of a significant tree on the roundabout meant the project required a special approach.

“The micro-tunnel bore has been hard at work in order to feed in the final lengths of water main pipe to be installed on Canning Street instead of the more traditional digging methods.”

Edge Underground was awarded the contract by JAYDO Construction.

For more information visit the Edge Underground website.

If you have news you would like featured in Trenchless Australasia Assistant Editor Sophie Venz at