Drought-proofing an entire city, reducing its storm water pollutants and adapting the city to climate change requires more than a building-scale solution. It requires a city-wide strategy addressing the sustainability of our city’s existing infrastructure and assets. We call it green infrastructure and the decentralised water master plan provides a blueprint for a water-smart and water-sensitive city.
More than half of the water infrastructure in the City of Sydney is over 70 years old. It’s time to rethink how we deliver the city’s drinking and non-drinking water supplies for the 21st century.
The water story so far…
Currently, our water strategy is to build remote large holes in the ground called dams, hope that it rains, treat all water to drinking water standards, pump it long distances to the city and then only drink two per cent of the water received.
Even if we take into account uses where we may drink the water, such as catering, showering or bathing, drinking water requirements amount to no more than half of our total water consumption.
The other 50 per cent of our water is used for non-drinking purposes such as toilet flushing, air conditioning cooling towers and irrigation of our parks and gardens. Put simply, uses that don’t need such a high quality of water. The current set up is inefficient, unsustainable and highly vulnerable to climate change.
What is decentralised water?
Decentralised water is about finding local solutions for our water needs, rather than rely solely on large-scale remote solutions. The plan for Sydney is an integrated and localised management of water, wastewater and stormwater – the three key elements of the urban water cycle within the City of Sydney.
This means planning and developing projects that achieve multiple objectives and working on the synergies of the three water cycle elements. Decentralised water is about improving water efficiency of the buildings and operations within the city, providing recycled water, stormwater and other locally available water resources for non drinking purposes and reducing stormwater pollution to improve the quality of our waterways.
The creation of the master plan
The Master Plan provides the best path for Sydney based on water efficiency, recycled water options, stormwater pollution reduction and cost. Ultimately the plan describes how best to configure these solutions, where they should be located and how they will perform.
The City of Sydney worked with GHD, the Institute for Sustainable Futures and P3iC to analyse water metering data, detailed floor space and comprehensive scenario planning that allowed a new understanding of the city’s urban water cycle. The City of Sydney consulted with a broad range of industry partners including Sydney Water as well as a community reference group during the development of the water master plan.
Key details of the Master Plan are:
Detailed layer analysis which helped to determine the best water solutions
Detailed graphics show the robust spatial layers and data analysis which formed the strategy. This includes maps of boundaries, catchment areas and floor space, water consumption, growth in water demand by 2030, stormwater, wastewater and groundwater volume and finally land use and type.
Decentralised water solutions
These solutions include reducing water amounts through improving water efficiency, developing local water supply options through recycling stormwater, rainwater, wastewater, sea water and groundwater for non-drinking needs and integrating more vegetation in our streets to slow down and filter pollutants from running into our waterways through water sensitive urban design.
Opportunities were first mapped to understand how much potential existed in which locations. Solutions were then designed to capture as much of these opportunities as practicable and cost-effective.
Twelve enabling actions
Implementing decentralised water solutions on a city-wide scale requires the City of Sydney working in co-operation with State and Federal Government.
The Master Plan details twelve enabling actions that would assist the implementation and delivery of the decentralised water master plan. They are included not as barriers that would prevent implementation but as enablers, to ensure the Decentralised Water Master Plan delivers its full potential.