Urban water sustainability in Australian cities: using the National Water Account to indicate the resilience in water systems

Abstract

Securing water in Australia is particularly challenging in the context of the country's high natural hydro-climatic variability, population growth and implications from emerging changes of climate pattern. To make informed decisions about Australia's future water security, sound and independent information is needed about the balance of supply and demand across the country. Under the Water Act 2007, the Bureau of Meteorology (the Bureau) was legislated to provide standardised water information across the country; information that previously was not readily available to the public in Australia. The Bureau's annual National Water Account, with its first publication in 2010, provides water resource management information across ten regions in an independent, accountable and reliable form. The accounts are built through close partnership with reporting partners from a wide range of organisations in each State and Territory, as well as other Australian Government agencies, to gather the best available water related physical and regulatory data. This paper discloses information on urban water availability, allocation and use in six major cities in Australia from the National Water Account perspective and emphasises the balance between water supply and demand over the past six financial years (2010-11 to 2015-16; 1 July to 30 June). Past accounts have shown that total water use in urban centres has steadily increased at the rate of 2-3 per cent annually. Water security across Australia relies mostly on surface water, particularly for the Canberra, Sydney, Melbourne and South East Queensland regions. In Perth, groundwater and desalinated water supply are now the major sources of water due to low surface water availability. In Adelaide and Melbourne, water supply through interregional transfers assist in mitigating poor storage inflows. Using data from the National Water Account, in an analogy to financial indicators, we have developed a number of indicators for water systems under the themes of sustainability and liquidity. This paper presents these indicators for the six urban centres, and shows how the indicators can be useful for a comparison of water supply stress, flexibility, security and resilience between regions as well as for highlighting emerging issues, prioritising and targeting resources.