The importance of setting targets
The water sector in Australia is in a unique position to decarbonise – while utilities have different regulatory bodies, customer sizes and diverse technical challenges, it is a non-competitive market with water and sewage prices largely being set by economic regulators, and the vast majority of utilities are state and/or local government owned. This enables open information sharing that is not seen in many other industries, which can accelerate the adoption of best practice solutions to decarbonise the sector, including identifying pathways for carbon reduction target setting.
“There has been a rapid escalation in the number of water utilities adopting net zero targets in the last two to three years, and an acceleration in the timeframes of existing targets,” explains Matt Lyon, WSP’s National Decarbonisation Lead – Water.
“This has led to utilities moving past historical challenges – such as regulatory approval barriers for higher cost, lower carbon initiatives in locations where state governments had non-legislated net zero targets – and has now progressed to where there is widespread endorsement of carbon reduction targets at the water utility board level.
“The methods used by utilities to move past historical challenges vary, with studies for consumers’ willingness to pay being a key driver for some. Regardless of location, there is a clear pathway for utilities to set carbon reduction targets, as demonstrated by most major Australian Water utilities now having Net Zero commitments or in the process of finalising them.”
To date the majority of water sector commitments (with the notable exception of Sydney Water’s 2040 target for net zero emissions across their value chain) have focussed on scope 1 and 2 emissions. This includes the fugitive emissions associated with their operations (such as wastewater treatment methane and nitrous oxide, and the consumption of fuels in fleet vehicles) and emissions from indirect energy consumption (such as electricity consumption from grid power).
Matt adds, “While a focus on scope 1 and 2 emissions is a great start, this doesn’t capture scope 3 emissions – sources outside of the direct control of water utilities – such as biosolids disposal, chemical manufacture, and construction related emissions. These scope 3 emissions sources can be significant, and while the facilities where these emissions occur are not in the direct control utilities, it is within their control to quantify the emissions sources, and assess alternatives to their operations, designs, or suppliers to influence the impact of these emissions.
“When working on designing water related projects, we need to shift our focus to considering whole of life emissions, rather than scope 1, 2 and 3 emissions. This could be best achieved through the adoption of carbon accounting frameworks such as PAS2080 and additional sector specific measurement guidance.
“Quite simply, we need to start measuring all major emissions sources associated with the lifecycle of assets. A significant step towards water utilities achieving this, could be to insert a clause in tenders for whole of life carbon to be measured as early as possible in the project phase and submitted at project stage gates. This would enable options phase carbon comparisons for inclusion in multi-criteria analysis, and structured reporting frameworks to update forecasts and targets.”
The barriers to measuring carbon
At present there is not a single comprehensive national guideline for estimating all emissions sources in the water sector in Australia.
“The current industry adopted measurement tools are largely limited to ad hoc calculators produced by utilities and consultants, and a national tool published by the Clean Energy Regulator – the National Greenhouse and Energy Reporting (NGER) Schemes’ Wastewater Domestic and Commercial Calculator,” explains Matt. “This calculator, while useful for federal government national reporting, is extremely limited when being used at a project level to look at whole of life emissions.
“A better alternative would be the creation of a sector guideline similar to that of Water New Zealand (NZ), who in collaboration with industry consultants including WSP, has released a NZ specific carbon accounting standard for methane and nitrous oxide.”
Another hurdle to measuring whole of life emissions is knowing what emissions data sources to use for specific products in construction. There are various lifecycle assessment tools and industry measurement tools available that estimate these sources, but emissions data is also now freely publicly available on various supplier products used in the water sector (such as concrete, steel and pipelines) through EPD Australasia.
“We have been encouraging all suppliers to develop Environmental Product Declarations (EPDs) for their products, as it is becoming a global standard for consistently publishing product specific emissions,” adds Matt. “I can see a future where the development of EPDs becomes a mandatory requirement for certain products as part of sustainable procurement policies developed by water utilities. We’re not there yet, but ultimately, we need industry to help drive suppliers to measure the carbon emissions associated with their products, which will inevitably lead to competition in developing lower carbon solutions.
“At WSP we put a line in the sand, having committed to halving the carbon emissions of our designs by 2030. To this end, we are are actively investing in being Future Ready™ by developing the way we measure carbon on projects, and the tools and processes we use to do so.
“We want to work closely with our clients and the water industry on the best way to consistently measure whole of life emissions, and to identify practical carbon reduction pathways and lower carbon design options for the sector.
“When evaluating emissions on projects, the value of carbon is also an important aspect. As our Advisory team has shown, Australian guidance on the impact of carbon for use in cost benefit analysis for infrastructure projects has historically been valued much lower than other countries. This may impact the viability of business cases or option selection, and requires careful consideration.
Focus areas for decarbonising
No two water utilities are the same, so quantification of emissions is an important step for utilities to complete before they begin to develop an emissions reduction strategy.
Matt says, “The level of emissions from sources will vary between utilities, depending on their assets and operations, and progress in decarbonising. I see six emissions areas that account for the majority of the carbon emissions in the sector – power consumption, wastewater treatment fugitive emissions, biosolids management, construction activities (particularly for new assets), chemicals, and fuel use.
Power consumption
Energy efficiency programs should be implemented (noting higher power consumption may be necessary to reduce fugitive emissions).
Renewable energy installations should be investigated as should the changing operational processes to be optimised for consuming renewable energy (e.g., through attenuation of flows overnight). Where renewables on site are not practical, green power purchasing agreements should be considered.

Wastewater treatment fugitive emissions
Investigation of physical measurement through established research programs, and subsequent process optimisation of nitrous oxide and methane emissions should be prioritised.
Over time these investigations will likely be expanded to sewer methane – potentially a large source of emissions not yet tackled by the industry in Australia.

Biosolids treatment, transport and disposal
Investigation of treatment technologies to reduce whole of life bisolids fugitivie emissions, transport volumes and to enable alternative reuse options and locations.
This may include established technologies such anaerobic digestion with energy recovery, and the re-emergence of thermal treatment systems such as pyrolysis and gasificaiton (which may also alleviate concerns on PFAS management).

Construction emissions
Quantification of emissions sources should be prioritised, and industry should work with suppliers and contractors to find lower carbon solutions.
This will likely lead to review of design standards for primary construction materials (such as concrete, steel, pipelines).

Chemical production, use and transport
Quantification of chemical emissions sources on relevant projects.
Reduction of chemical use where practical, and engaging with suppliers to identify decabonisation pathways.

Fleet fuel use
Optimisation of fleet operations.
Conversion of fleet vehicles to cleaner fuel sources where practical.