Central Interceptor celebrates breakthrough

Micro-tunnel boring machine (mTBM) ‘Domenica’ has finished its first drive, successfully breaking through at the Haycock Ave shaft on 10 December.   

Domenica was placed in a 2.1 m diameter pipe for the link sewer that will run between Miranda Reserve in Avondale to the main Central Interceptor wastewater tunnel, connecting up at May Rd in Mt Roskill. 

Once complete in 2026, the Central Interceptor will store and transport both stormwater and wastewater to Watercare’s Māngere Wastewater Treatment Plant, preventing wet-weather overflows and significantly cleaning up Auckland’s waterways.

Watercare delivery manager Chris McCarthny said the process has not been the post seamless for the team. 

“We started tunnelling from our 55 m deep May Rd shaft on this first section of the link sewer in June,” said McCarthny. 

“Domenica was making great progress, working 24 hours a day, five days a week and laying up to 15 metres of pipe a day. And then Covid-19 threw a spanner in the works.”

Work was placed on hold for one day as Auckland entered alert level 4 in August before the project received a crucial exemption.

“With this method of tunnelling called pipejacking, where the micro-TBM and all of the pipes are pushed along from the base of the launch shaft, the machine can get stuck if it sits stationary for too long,” McCarthny explained.

“When we entered lockdown, Domenica was in almost the worst possible position – more than 70 m below the ground and in the middle of residential Mt Roskill – so it was critical to get her up and running again so she didn’t get stuck.” 

The Central Interceptor project operated under a skeleton crew during level 4 restrictions to keep the mTBM moving forward, covering just half a metre a day. 

“Thanks to the incredible people on the project, we were able to implement our level 4 protocols within 48 hours of the announcement and continue tunnelling, avoiding the potentially disastrous consequences of a stuck machine.”

This is the first of many anticipated breakthroughs on the five-year tunnelling project, and according to executive program director Shayne Cunis, the team is pleased to have completed the milestone ahead of Christmas. 

The mTBM will now be retrieved from the shaft at the Haycock site and serviced before it is launched again next year. 

From there, ‘Domenica’ will begin a 720 m journey back to Haycock Ave from the Dundale Ave site in Blockhouse Bay. 

Meanwhile, the Central Interceptor’s main mTBM ‘Hiwa-i-te-Rangi’ launched back in July has laid more than 145 rings and traveled more than 240 m of its 14.7 km journey. 

Hiwa-i-te-Rangi is expected to start tunnelling deep beneath the Manukau Harbour in winter next year.

For more information visit the Watercare website. 



Ballarat Sewer Build Stage 1 complete

Central Highlands Water (CHW) has successfully completed Stage 1 of the Ballarat Sewer Build. 

Stage 1 of the project commenced in April 2021 and required an investment of more than $25 million into the Ballarat region. 

The team at CHW faced many challenges throughout the project including construction interruptions due to COVID-19 and severe weather events, and the company thanked the community for its ongoing patience and understanding. 

“The understanding shown by both our business community and residents has made a highly complex project achievable,” a spokesperson for the company said. 

Stage 1 of the project saw the installation of around 1 km of sewer pipe, between4 and 6 me beneath the CBD, along Peel Street, Eastwood Street and Anderson Streets and East and West. 

The construction process involved the compaction of more than 13,000 t of rock and two micro-tunnels bored beneath critical traffic intersections. 

Microtunnelling techniques were used where possible to minimise ground disturbance; however, attempts at Little Bridge Street were unsuccessful due to unstable ground conditions and open-trench methods were necessary. 

Around 220m3 of concrete was poured in the three large sewer connections made into the existing network.

The project took the CHW a total of 22,000 working hours. 

Stage 2 of the Ballarat Sewer Build will cover White Flat Oval to Rest Street, and is expected to commence in 2022. 

When all stages are complete, the Ballarat Sewer Build will duplicate the existing sewer line from Ballarat East to South. 

According to CHW, the pipeline duplication will service the community for another 100 years. 

For more information visit the Central Highlands Water website. 

Rob Carr's fleet of tunnel boring machines

Rob Carr: Flexibility is the key to success

Backed by more than 30 years’ experience, Rob Carr has become a reputable name for utilities infrastructure and a market leader in microtunnelling and complex underground works. 

Since it joined VINCI Group, the company has been able to improve its financial capability to bid, design and construct bigger and more challenging projects. 

One of the keys to the company’s success is its fleet of 30 microtunnelling machines, with the largest diameter being 2,180 mm, covering all ground conditions.  

“With our fleet of 30 microtunneling machines, we cover a range of pipeline diameters for trenchless construction,” a spokesperson for the company said. 

The machines are supported by a wide ranging ancillary equipment fleet in the form of control cabins, jacking frames, slurry separation tanks and systems, gantry cranes, and more. 

“These tools are fundamental when it comes to trenchless construction as it improves accuracy,” the company said. 

Rob Carr uses trenchless techniques to successfully construct tunnels for pipeline infrastructure beneath major roads, railways, runways, waterways and environmentally sensitive areas. 

The company uses two main techniques for mirotunnelling: slurry pressure balanced micro tunnelling, and pilot auger soil displacement tunnelling. 

Recently, the company also invested in German  Herrenknecht AVN technology to facilitate the growth of the business into larger scale tunnelling projects.

For more information visit the Rob Carr website. 

Iplex Restrain

Restrain Sewer Pipe – made in Australia by Iplex

Since 1938, Iplex has worked with asset owners and contractors to find solutions for effectively repairing, rehabilitating or replacing existing pipelines while protecting the environment and local residents. 

Restrain™ Sewer Pipe  was specifically designed by Iplex for both new sewer networks and for the repair and replacement of underground gravity sewer infrastructure.

The need for a watertight, instantly restrained joint motivated Iplex to design and deliver Restrain – a PVC-U thread joint pipe with a rubber ring seal.

It is not your everyday threaded connection: it was designed for both trenched and trenchless installation.

Restrain is designed to keep boring diameters small while maximising flow, for long shot length with high push/pull strength and instant retention with a positive seal in the joint.

Restrain capitalises on the characteristic of PVC-U and is suitable for use in deep installations. The unique qualities of Restrain maximise the use of existing maintenance shafts as launching pits. 

Restrain is suitable for many different installation methods, including open trench and trenchless installations: such as horizontal directional drilling (HDD), auger boring or guided boring, micro-tunnelling and more. 

While previously imported, Restrain is now proudly manufactured in Australia, and meets strict national and product standards, and also has a positive WSAA appraisal.

Iplex has been recognised for its exceptional customer support and end-to-end capabilities and will be holding a technical webinar to allow customers to hear from the Iplex product & technical experts and also ask questions about Restrain.  The webinar will be hosted on Thursday 25 November at 11:00 am AEDT and will run for approximately 40 minutes.

Click here to register. 

For more information visit the Iplex website. 

watercare wastewater scheme upgrade

Watercare upgrades wastewater scheme in north Auckland

According to Watercare, Warkworth is expected to grow significantly in population, with up to 20,000 people migrating to the area over the next few decades.

The utility is undertaking a number of significant wastewater infrastructure projects to accommodate this anticipated growth, one of which is the Warkworth to Snells transfer pipeline. 

Watercare is tunnelling more than 5 km of new pipeline from Lucy Moore Memorial Park to the new wastewater treatment plant in Snells Beach.

Tunnelling will be carried out deep underground by direct pipe tunnelling — a method that was successfully deployed on the Snells-Algies wastewater outfall. 

The Snells-Algies wastewater pipe and outfall was constructed back in 2020 as the first phase of a three-stage scheme to supply the Warkworth and Mahurangi East communities north of Auckland. 

Warkworth wastewater map. Image: Watercare
Warkworth wastewater map. Image: Watercare

Micro-tunnelling expert McConnell Dowell was awarded the design and construct contact by Watercare in March 2019. 

The project set a new world record for the longest direct pipe drive by a micro-tunnel boring machine (MTBM), reaching 2021 m – a whole 92 m further than the previous record set by McConnell Dowell in 2018. 

The Warkworth to Snells pipeline will be delivered in conjunction with the Lucy Moore Memorial Park wastewater pump station and the Snells Beach wastewater treatment plant. 

The Warkworth wastewater scheme is expected to be completed in 2024. 

For more information visit the Watercare website. 

85 years of Interflow

Interflow celebrates 85 years

Throughout its history, Interflow has pioneered technologies and renewal methods that have been well received for their innovation.

The company was founded in 1936 by Harold ‘Bill’ Weaver, whose mission it was to support the growth of budding communities along the east coast of Australia.

Weaver and his original team at Interflow constructed water, sewerage and drainage systems for developing towns, earning him a reputation as a change maker.  

His ability to identify gaps in the market and develop services to meet the needs of his customers allowed him to expand the company’s operations across the country. 

Since the 30s, Interflow has been generation-led and family owned, with leadership handed down from father to son now over three generations 

From proactive asset management to emergency repairs, the company is dedicated to developing bespoke solutions that satisfy its customers’ needs: robust, sustainable pipeline infrastructure that will service the growing requirements of the community for generations to come.

As early as the 1990s, interflow pioneered the use of trenchless technology to improve efficiency, reduce costs and minimise impact to the environment and community. 

Interflow 1991
In 1991, Interflow signed its first 20-year exclusivity deal with partners Rib Loc.trench

In 1991 – 30 years ago – the company signed its first 20-year exclusivity deal with partners in innovation Rib Loc. 

Together, the companies provided hundreds of local councils and water authorities with industry-leading pipeline infrastructure services, restoring assets for an expected period of 50 years. 

The companies continue to share a working relationship today. 

Today, managing director and Bill Weaver’s grandson, Geoff Weaver, is responsible for the company’s operations, establishing an international foothold in New Zealand, and negotiating two twenty-year exclusive Australasian licenses for spirally wound rehabilitation products. 

At 85 years, Interflow is Australia’s largest provider of Trenchless pipeline solutions, establishing itself as the preferred delivery partner within Australian markets. 

Geoff Weaver said the company’s ongoing success has been guided by the core values laid out by his grandfather. 

“My grandfather’s ethos was simple. He was committed to challenging the status quo and finding new and better ways to do things,” he said.

“Each generation of leadership has been responsible for refining these methods and developing new technologies to further improve the experience of our customers and communities.”

Interflow now employs over 600 people across Australasia, and the company continues to expand the range of services it provides. 

“As we celebrate this incredible milestone, we look forward to the next 85 years of supporting our customers and uplifting communities with pipeline infrastructure solutions for generations to come,” Weaver added.

For more information visit the Interflow website. 

Lockerbie Sewer Mains Project

YVW works with elders on Lockerbie Sewer Main

Construction activities commenced in March 2020 for the 9 km sewer pipeline between Donnybrook and Beveridge, with the sewer expected online by the end of the year. 

The Victorian Planning Authority is predicting that by 2050 the area will be home to around 300,000 people , and the pipeline is expected to cater for this population growth. 

The Lockerbie Main Sewer will collect and transfer sewage flows from a majority of the proposed new developments and communities in the Donnybrook, Beveridge and Lockerbie area.

The joint venture (JV) has engaged extensively with the Wurundjeri Woi Warring Cultural Heritage Aboriginal Corporation to identify the potential impact excavation may have on culturally sensitive areas. 

The collaboration included a 12-month cultural salvage program involving a combination of hand and mechanical archaeological digs to identify, record and preserve artefacts and ensure the area remained protected for generations to come.

Nina Braid is the Aboriginal partnerships manager at Yarra Valley Water. 

“At Yarra Valley Water we are committed to reconciliation and building the trust understanding with Traditional Owners as part of our commitment to helping communities thrive,” said Braid. 

Darren Wilkins is the delivery manager of capital projects and utilities with Ventia. 

“This area has high level ground wanter content, so the communities traditionally used to meet in these areas,” said Wilkins. 

“Before we even started onsite, those areas of potential significance were roped off – they’re no-go zones for us.”  

Wilkins said that if the operators were to find anything of potential significance in areas deemed to be clear, the team must stop work immediately and notify the local elders. 

The pipeline will be constructed along the western side of the Melbourne-Sydney railway line north of Minton Street, then crosses the railway line and hugs the eastern side of the rail line to its southern end in Donnybrook.

Yarra Valley Water said the Traditional Owners’ connection to country influences the way the company works and engages with the land. 

Construction is expected to be completed in late 2021 and the completed Lockerbie Main Sewer will begin operating in late 2021.

For more information visit the Yarra Valley Water website. 

Construction site closure

Melbourne construction set to resume 5 October

Major trenchless and tunnelling works have ground to a halt across Melbourne since the Victorian Government’s announcement of the mandatory closures last Tuesday. 

Victoria’s Big Build has suspended works across some of the state’s biggest projects in metropolitan Melbourne, City of Ballarat, City of Greater Geelong, Surf Coast Shire and Mitchell Shire. 

These include works on the West Gate Tunnel Project as well as the Metro Tunnel Project, set to be completed in 2025. 

Big Build said it would be working closely with its building parters to comply with construction-related public health orders for when works recommence. 

This includes implementing strict measures to minimise workforce close contacts, such as staggered shifts and industry consultation to implement COVIDSafe meal and rest-break arrangements for our workforce.

Limited exemptions have been available to enable some workers to attend sites to respond to emergency or perform urgent and essential work.

Across town, Central Highlands Water (CHW) been issued an exemption for the Ballarat Sewer Build, which was declared a critical water infrastructure project. 

CHW said workers on the Ballarat Sewer Build are subject to the same requirements as construction workers across the entire industry regarding vaccination. 

All sites will be required to demonstrate compliance with the Chief Health Officer Directions prior to reopening on 5 October, including evidence of first vaccine dose. 

For more information visit the Victorian Health Building Authority website.