Supporting the circular economy across Victoria

The Water Minister’s Climate Innovation Challenge had three Victorian water utilities collaborate on a unique circular economy solution to reduce the industry’s carbon footprint.

The water industry in Victoria is well-known for its collaborative approach to innovation, which is reflected in the Water Minister’s Climate Innovation Challenge. This challenge provided a unique opportunity for water corporations to demonstrate their commitment to creating positive outcomes in the face of climate challenges and the circular economy. The goal was to strengthen Victoria’s climate resilience and shape the water industry’s future through collective effort. Winners of the challenge received funding to support the aims of their projects.

Intelligent Water Networks (IWN) was entrusted by The Hon. Harriet Shing, Minister for Water, and collaborated with the Department of Energy, Environment and Climate Action (DEECA) to run the program. Thirteen submissions were made to the Climate Innovation Challenge, and six progressed to the final stage.

One of the winning submissions came from three water utilities: Yarra Valley Water, Barwon Water, and North East Water (NEWater). The combined project was titled “Meta-analysis of low-carbon cement alternatives for water industry applications.” It sought a new approach for water utilities to focus on lowering the greenhouse gas emissions associated with cement used in the water industry, forming part of a broader examination of the circular economy.

Dr Lisa Ehrenfried (Yarra Valley Water), Hayley Vinden (Barwon Water) and Dr Jill Fagan (NEWater) presented their project to the awards ceremony.

“Cement generates about eight per cent of global carbon emissions,” said Dr Ehrenfried. “As a country, it would have the third largest carbon footprint in the world.”

The group estimated that if the Victorian water corporations used low-carbon cement alternatives, they would eliminate the equivalent of 25,300 cars from the road over the next five years.

Carbon emissions in construction

Dr Ehrenfried’s background in materials science led her to the water industry. Her expertise has given her a unique perspective on increasing the use of recycled materials in construction and maintenance processes, forming a vital part of the circular economy.

“When pipes are installed underground, they are usually embedded in gravel or sand,” she said. “It’s important to note that the gravel or sand doesn’t have to be brand new. We now have approval to use recycled aggregate, sand, or crushed glass to secure our sewer pipes. Given the high carbon emission from concrete, we are also interested in how to make this ubiquitous material more sustainable, thus reducing its carbon footprint and environmental impact overall.” Several low-carbon concrete products on the market utilise waste material such as slag or fly ash.

One of the industry’s major challenges is understanding scope three emissions, which are separate from scope one and two emissions. When the team investigated scope three emissions, they found that water utilities tended to have significant emissions.

“A considerable part of these emissions come from cement,” Fagan said. “Since cement contributes a substantial portion of global carbon emissions, the water industry’s extensive use of cement and concrete presents a significant opportunity to lower emissions by using environmentally friendly concrete products.”

The team understood that the market existed for these products, but there had yet to be much uptake within the water sector. That’s why they wanted to set the industry on a path to an increased uptake of low-carbon products, particularly cement.

“Early last year, I hosted a discussion on green concrete with other water corporations,” Vinden said. “The discussion was initially focused on Victorian water corporations but grew to include many water corporations nationwide. During that meeting, I realised we were all working to reduce our carbon footprint. Still, there was no one-stop shop to showcase innovative and sustainable products for water and wastewater infrastructure.

Outcomes of the project

“We wanted to create a comprehensive list of low-carbon products suitable for water infrastructure so that the entire Victorian water sector could benefit,” Vinden said. “This would help to drive the entire sector towards zero net emissions.”

“We know that these low-carbon concrete products are already in use in other industries, such as transport and office buildings.,” said Fagan. “We wanted to understand the alignment of these products with the water sector-specific codes and standards.”

“The consultants have produced a pathways document to guide widespread uptake of low-carbon concrete within the sector, as well as a tool to support all users in determining the best low-carbon product to utilise,” said Vinden.

In addition to low-carbon concrete, opportunities for using recycled products are rapidly expanding within the water industry. For example, water utilities are using recycled materials to promote the circular economy in the creation of access tracks to assets.

“We are using recycled aggregate to build site access tracks,” Dr Ehrenfield said. “We are also using bollards made from recycled plastics. One specific contractor we work with uses recycled car tyres to make protective ramps over temporary pipes that many people would see during water main replacement works in their local area. This way, we are protecting the temporary pipes without generating additional plastic.”

These products, alongside many others, are collated in the Recycled Products Database, a separate project funded by DEECA, which will benefit all Victorian water corporations.

What was learned?

One of the most important things I learned is what low-carbon concrete is available for which water industry applications and how the industry needs to evolve to maximise the the use of alternative materials.

“It’s good to have that rigour and assessment around what we know, what we don’t know, and where we need to go next. We now have an excellent overview of all the materials we should consider when it comes to low-carbon cement,” said Dr Ehrenfried.

“There are still meetings to be had with DEECA and IWN, as well as the Water Services Association of Australia (WSAA), to show the water sector how they can make best use of and progress in concrete alternatives.

Fagan said the project delivered exactly what they sought. She was pleased with the outcome and was surprised by the interest levels from across the country.

“We heard many fantastic stories from overseas,” she said. “Some of those organisations are not only using low carbon construction materials but have also started intentionally using construction methods that lower emissions, such as trenchless techniques. They are a couple of steps ahead. There is so much for us to learn. We have set up ongoing knowledge exchange and discussions every six months.”

Industry interest in this circular economy project

The industry has embraced this project, and receiving $30,000 from the Water Minister’s Climate Innovation Challenge has helped it get off the ground.

“We had an incredibly interactive workshop,” said Dr Ehrenfried. “The project shows real momentum building within the water sector to think more deeply about the carbon footprint through construction. The Climate Innovation Challenge saw us focus on low-carbon cement and what is available on the market now. As part of that, we had some fascinating discussions with people working within the water industry in the UK. It was great to hear about some of the lessons learned so we could apply them to our own backyards.”

Fagan pointed to the wide range of conversations they had across the industry. There is considerable interest and enthusiasm for what the project could provide for different water utilities.

“We are now looking at what the best path forward is,” she said. “Part of our funding will be used for a couple of targeted presentations to water industry groups to explain what we have learned and done over the past couple of months. It allows industry stakeholders to learn about the opportunities and collaborate on next steps.”

Vinden agreed that there is considerable enthusiasm across the industry to see what products could be used in the future.

“There are many opportunities and interest in using green concrete,” said Vinden. “That’s fundamentally circular in nature, given the use of recycled fly ash and slag. This will help all water corporations to reduce their scope 3 carbon footprint. Trialling recycled or greener products will allow the industry to study them to determine whether they meet the strict quality criteria.”

For more information, visit https://www.iwn.org.au/ and https://vicwater.org.au/