Enabling a water-sensitive city

The population of Greater Sydney is expected to grow to eight million by 2056, and by 2060 an additional 180 billion litres of water will be required to meet growth demands.

Climate change also means that the frequency, distribution, intensity and duration of climate-related events pose potential risks to water supply.

To meet the demands of a growing population and ensure a secure water supply for Greater Sydney for generations to come, Sydney Water is working on a range of solutions with an aim to enable a water-sensitive city.

Paul Higham, Head of Strategy and Enterprise, Sydney Water, presented at the Committee for Sydney Resilience briefing recently to discuss how the water utility is navigating the challenges and opportunities that lie ahead, including climate change and a growing population coupled with increasing urbanisation.

Higham said the challenge, and therefore the opportunity, is how Sydney Water keeps providing its products and services to a growing customer base in a future of changing climate, and at the same time, how quality of life and the liveability of the city are enhanced to meet the growing aspirations of its customers and communities.

“The role of Sydney Water is changing. We are not just service provider; we also play a key role in shaping the growth and identity of our city,” he said.

“Our long-term vision is to enable a water-sensitive city, one that is nourished by and respects its waterways and water resources. This means not only having safe, equitable and affordable water, but also beautiful waterways, and green and blue spaces that sustain communities and cultural connections.

“Moving away from a traditional water management requires an appreciation that we are planning across the water cycle, and investment decision-making will have to take into account community and asset resilience.”

Sydney Water is investing in initiatives and infrastructure that will help secure a sustainable and more resilient Greater Sydney including;

The Greater Sydney Water Strategy

One priority of the NSW Government’s draft Greater Sydney Water Strategy (GSWS) is to ensure water systems are sustainable for the long-term and to build resilience in these systems to drought and climate change. Purified Recycled Water (PRW) is one of the options being considered in the strategy, alongside more traditional water sources such as dams and desalination, and one that Sydney Water sees as being able to meet both future additional water needs and sustainability and resiliency outcomes.

“PRW could meet 25% of Sydney’s water needs by 2056 and it can reduce our reliance on energy-intensive desalination plants, offset the need for expensive drinking water investments and improve environmental flows for our rivers,” Higham said.

Urban typologies

Last year, Sydney Water produced a piece of research demonstrating the benefits of innovative stormwater and integrated water management for achieving liveability and environmental outcomes.

Modelled on a range of development scenarios in the Western Parkland City, the ‘Urban Typologies and Stormwater Management Report’ demonstrates how total water cycle management can be integrated with urban planning to keep water in the landscape for greening and cooling.

“Keeping stormwater in situ through a range of measures, such as deep soil areas, permeable pavements, and irrigation and bioretention systems, can reduce stormwater run-off by up to 75% and mitigate the impacts of run-off on the health of our waterways,” Higham said.

“Our urban typologies have also addressed the broader challenge of urban heat, which we know is a major challenge in Western Sydney and one that will be compounded by rising temperatures associated with climate change.”

This modelling shows that implementing these typologies has the potential to reduce peak temperatures in the Aerotropolis by 4.6 degrees on an extreme heat day and reduce the number of extreme, very strong and strong heat stress days per summer.

Carbon Zero Plan

Sydney Water has recently released its Carbon Zero Plan, which sets out long-term directions for the business to reach zero carbon emissions by 2030 and for its supply chain to reach the same by 2040.

The corporation is working to reduce its energy use by improving energy efficiency and generating its own renewable electricity, which in turn will drive down costs for both the organisation and its customers.

“We have for some time been integrating renewable energy generation into our own operations to produce up to 20% of our energy needs primarily through biogas cogeneration and hydroelectricity. This is where the energy–water nexus comes into play as we are leveraging our existing infrastructure and materials to address both our energy needs and operational responsibilities,” Higham said.

“We are using biogas to generate our own energy at our Malabar Wastewater Treatment Plant (MWTP), producing around 53 gigawatt hours per year of electricity.”

Sydney Water has also partnered with energy infrastructure company Jemena to produce biomethane at Malabar, announced earlier this year. This will see green gas power Sydney homes and businesses within the next few years. Sydney Water will produce the zero-emission, high-quality biomethane gas at the MWTP, which will then be injected into Jemena’s NSW gas distribution network to meet the gas demand of approximately 6300 homes.

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