Sustainability

Sustainability is at the heart of the design and delivery of Suburban Rail Loop (SRL) and is embedded across all parts of the project – from planning and construction all the way through to operations.

With major construction of SRL East between Cheltenham and Box Hill now underway, here are just a few of our sustainability objectives and actions already in place to help build a greener future.

Leadership

Ratings systems

SRLA uses the Infrastructure Sustainability Council and Green Building Council of Australia rating systems to drive, verify, and benchmark progress in sustainability during planning, design, and construction.

SRL East contractors are working to achieve an IS v2.2 - Gold rating from the Infrastructure Sustainability Council (ISC) for the tunnelling packages, and we continue to work with the Green Building Council of Australia (GBCA). The SRL East stations have been registered with GBCA since 2021, and all stations will target a 5-star Green Star rating.

Ground freezing

An innovative ground freezing technique is being used to build some of the safety passages between the twin tunnels, avoiding the need for ground treatment from the surface. This will reduce disruption to residents and roads on the surface by more than 90%. This approach also reduces emissions and material requirements.

The ground freezing technique involves pipes drilled deep underground and injected with chilled brine (salt and water). The brine will temporarily freeze the surrounding soil – stabilising it and making it safe for our teams to build the safety passages.

Energy and carbon

Electric plant and vehicles Powered by renewable electricity, our crews carpool in electric vehicles on site, cutting noise and air pollution. Across Tunnels South and North, electric vehicles, machinery and equipment have saved over 60,000 litres of fuel
Powered by renewables All tunnel boring machines used on SRL East will be powered by 100% renewable electricity. All trains will be powered by 100% renewables, and all 6 new stations target a 5-star Green Star rating

Water

Reducing water use

During initial and early works, polymer dust suppressants were used to stabilise soil and reduce dust during works on site. This technique is non-toxic, biodegradable and reduces water use.

We’re also reducing the need for water carts to control dust on SRL construction sites by using polymer binders on excavated soil – keeping dust from blowing around in dry and windy conditions.

Where possible, non-potable water is being used during construction and operation – including additional targets for use in station buildings and the train stabling facility.

Materials & Waste

Concrete hardstand

Recycled concrete hardstand – a type of pavement – is being used at the TBM launch site at Clarinda to reinforce the ground so it can withstand heavy loads from trucks and equipment. Each layer of pavement is made from recycled materials including asphalt, ceramics and crushed concrete.

Noise Walls

Walls made from recycled plastic milk bottles are helping reduce noise from ventilation fans at the tunnel boring machine launch site in Burwood. The walls and acoustic materials inside them can also be recycled.

Drainage pipes

Made in Australia from 100% recycled plastic, these drainage pipes have been installed at our Clarinda site. One 630mm RPM pipe is made from up to 5000 milk bottles.

Guard barriers

In an Australian first for a major infrastructure project, 100% recycled ‘crumb rubber’ barriers are being used at our Heatherton and Clarinda sites. The barriers are made from recycled tyres – each one is made from approximately 56 passenger tyres.

Recycled surface

A recycled 'crumbed rubber' underlay was used to build the new Clayton community play space surface. The rubber underlay was made using 28.8 tonnes of recycled tyre material.

Image shows recycled rubber guards on SRL worksite — Recycled rubber guards

Large recycled rubber guards being used on SRL worksite. — Recycled rubber guards

Image shows recycled concrete hardstand being used on SRL site — Concrete hardstand

Image shows recycled and reusable noise walls being used at SRLs Burwood site — Noise walls

Image shows recycled drainage being used at SRL Clarinda site — Recycled drainage pipe

Kids playing basketball in Claytons new open space. — Recycled surface

Transport & mobility

Traffic safety

In preparation for major construction, we built and upgraded streets, traffic signals, and walking and cycling paths in the neighbourhoods around the new SRL East stations. This will improve traffic, pedestrian and cycling safety during major construction of SRL East.

Sparkles on a bike sustainability

Community & social legacy

Aboriginal cutterhead art

A proud Wurundjeri and Dja Dja Wurrung man, Hayden Roberts is an emerging artist whose piece ‘Footsteps of the Past’ features on the cutterheads of 2 tunnel boring machines (TBM) [link to web story and video] set to build a section of the SRL East twin tunnels through Wurundjeri Woi Wurrung Country – between Glen Waverley and Box Hill.

Hayden is the owner of Fast Lane Designs, and works for Wurundjeri in the Narrap Unit at Wurundjeri Woi-wurrung Aboriginal Cultural Heritage Corporation as a Bush Ranger Trainee, with his work on Country informing his art – weaving together culture, heritage, connection to environment and storytelling.

Panku Safety Solutions

Panku Safety Solutions is an Aboriginal-owned business supplying SRL workers on Tunnels South between Cheltenham and Glen Waverley with specialist personal protective equipment (PPE) and tailored support – including gloves and PPE vending solutions.

CareerSeekers partnership

CareerSeekers is a social enterprise addressing employment barriers faced by refugees and asylum seekers. Five employees who arrived in Victoria as refugees are now working for Tunnels North contractor Terra Verde, which is building the twin tunnels between Glen Waverley and Box Hill.

Yahya is an experienced and qualified HR professional from Eritrea, with extensive professional experience overseas, including as a Senior Human Resource Manager. After arriving in Australia and working part-time in a warehouse, production line and as a cleaner, he’s now a Supplier Mobilisation and Reporting Coordinator on Tunnels North and about to develop his career through further study.

Australian Spatial Analytics

Tunnels South contractor Suburban Connect has partnered with social enterprise Australian Spatial Analytics (ASA) to create jobs and career pathways for neurodivergent people in the data sector. The 12-month supported work placement on SRL provides entry-level roles in geospatial and digital engineering, supporting neurodivergent people to apply and develop their unique skills and strengths on-the-job.

All women tunnelling crew

The world’s first all-women tunnel boring machine crew is already breaking down barriers and creating new pathways for women in construction.

More than 900 women applied, and the crew is now on board. Successful applicants – including those new to construction – receive specialist training from the Victorian Tunnelling Centre in Chadstone, as part of a 3-year TAFE course.

The all-women crew is one of several crews working for Tunnels South contractor Suburban Connect to build the twin tunnels between Cheltenham and Glen Waverley.

Social procurement

SRL East delivery partners have minimum targets for the employment of women, First Peoples, priority Jobseekers, and apprentices, trainees and cadets. Targets are also set for their procurement from social benefit suppliers including Aboriginal-owned and managed businesses, and social enterprises. This is in alignment with Victoria's Social Procurement Framework, Building Equality Policy and Local Jobs First Policy.

So far, we have engaged more than 100 certified Victorian social benefit suppliers in areas including civil construction, surveying, traffic management, and training and education services – including 67 Aboriginal owned and managed businesses, and 42 social enterprises.

Environmental protection & enhancement

Tree planting

More than 4000 trees are being planted as part of SRL East to create cool, green and inviting spaces in the areas around the new SRL East stations – with planting already underway.

As part of initial and early works, Kooyongkoot Alliance planted 500 native plants along Gardiners Creek in 2025 – supporting biodiversity and restoring habitat.

Buzzing burbs

'Buzzing Burbs' is a program to create more friendly places for native pollinators including birds, bees, bats, butterflies, and other wildlife in the SRL East neighbourhoods.

This will support healthy ecosystems, biodiversity, climate resilience and habitat connectivity.

Resilience and climate change

SRL East will be designed to be resilient to climate change and natural hazards and to support a resilient transport network.

Our tunnelling contractors for SRL East have completed a Climate Change Risk Assessment and prepared a Climate Change Resilience and Adaptation Action Plan, with ongoing integration of risks and mitigation measures. These plans ensure we are future proofing the infrastructure Victorians will use for decades to come.

Want to learn more about sustainability on SRL?

Check out our latest sustainability report

Clayton March 2025 render sustainability