Rating B (Moderately Effective)
In Australia, water usage and availability have changed significantly over the last decade due to climate change as well as human patterns of water use. These two factors have resulted in shifts in rainfall patterns, temperature extremes, and community tension around the sustainable use of Australia’s water resources now and in the future. In Australia, the agricultural sector uses the most water, accounting for 72% of total water consumption in 2020-21, or 9,978 gigalitres (GL) of water, mainly for irrigation crops and pastures. The second largest water user was the industrial water supply, sewerage, and drainage services sector, which accounted for 12% of total water consumption in 2020-21. This sector used 1,646 GL of water, mainly to supply households and industries. The third largest water user was the household sector, which accounted for 13% of total water consumption in 2020-21. This sector used 1,808 GL of water, mainly for domestic purposes such as drinking, cooking, cleaning, and gardening. The mining sector also uses much water, although it is not required to report its full water use, and data is frequently challenging to obtain. Coalmining and coal-fired power in New South Wales and Queensland draws about 2,383bn liters of water, returning 1,970bn to the environment but often in polluted and processed form.
Source: Australian Government Bureau of Meteorology, “Water in Australia 2019-2020”. http://www.bom.gov.au/water/waterinaustralia/files/Water-in-Australia-2019-20.pdf
According to the Australian Bureau of Statistics, rainfall, surface water availability, and reliability vary across regions and seasons and are influenced by climate change. Australia has experienced a decline in cool-season rainfall across southern and eastern regions, which are home to major population centers and agricultural areas. According to the Bureau of Meteorology and CSIRO, southeast Australia has experienced a 15% decline in late autumn and early winter rainfall and a 25% decline in average rainfall in April and May over the past two to three decades. This has reduced the inflows to streams, rivers, lakes, and dams that supply water for urban and rural use. For example, inflows to the Murray-Darling Basin, Australia’s most extensive river system, have halved over the past 20 years. This has had a significant impact on agriculture. Agriculture depends on reliable and sufficient water supply for crop production, livestock watering, and processing. The Murray-Darling Basin, Australia’s most important agricultural region, experienced an extreme drought with the lowest rainfall on record. This reduced agricultural output as well as led to the Black Summer fires.
Source: Australian Government Bureau of Meteorology, “Water in Australia 2019-2020”. http://www.bom.gov.au/water/waterinaustralia/files/Water-in-Australia-2019-20.pdf
Another climate factor that affects water usage is temperature. Australia has warmed by about 1.4°C since 1910, projected to continue under greenhouse gas emissions scenarios. Higher temperatures increase water evaporation from soils, plants, and water bodies, reducing the amount of water available for use. They also increase the demand for water for irrigation, cooling, and domestic purposes. Higher temperatures also exacerbate the severity and frequency of droughts and heat waves, which reduce soil moisture and vegetation cover and increase the risk of bushfires and dust storms. Climate-related sea-level rise is also a substantial problem for Australia, affecting residential infrastructure, unique coral reefs, and precious cultural heritage. For example, the Torres Strait Islands, which are low-lying and densely populated, face threats from coastal erosion, inundation, saltwater intrusion, and damage to infrastructure and cultural sites. The Sydney coast in New South Wales, which has a high concentration of population and infrastructure, is exposed to storm surges, wave overtopping, and coastal squeeze. The Ningaloo coast in Western Australia is home to a World Heritage-listed coral reef system sensitive to changes in water temperature, acidity, and sedimentation due to sea level rise.
The industry and urban sectors have also been impacted by water changes brought about by climate change. Reduced water availability can affect the productivity and profitability of industrial activities and their environmental impacts. For example, reduced water availability can limit the output of thermal power plants that rely on water for cooling or increase their greenhouse gas emissions if they switch to alternative cooling methods. Reduced water availability can also affect the extraction and processing of mineral resources, such as coal and iron ore, which require large amounts of water. This has been experienced in areas of high mining activity, such as the arid semi-desert Pilbara region in Western Australia and the Hunter Valley in New South Wales.
In the urban sector, reduced water availability has led to water restrictions, higher water prices, lower water pressure, and increased risk of waterborne diseases. Many Australian towns and States are now used to water restrictions, most of which remain permanently in place. Some States, like Western Australia, have developed an advanced water recycling culture. For example, remote mining towns use wastewater to irrigate fields and community facilities, while Perth injects its wastewater into the aquifer to reuse in naturally filtered form.
Climate-related floods are causing severe damage to Australian residential areas. For example, the unprecedented floods in Northern Rivers, NSW, and southeast Queensland in March 2022 caused deaths and devastation and disrupted health and other services and facilities. The “Great Deluge of 2022” caused repetitive flooding across Queensland, New South Wales, Victoria, and Tasmania. The Climate Council calculated that the average cost per household of extreme weather disasters increased by 73 percent from the ten-year average to $1,532 in 2021-2022.
While Australia has lagged behind the world in taking action to reduce carbon emissions that are exacerbating the country’s water issues, it has implemented various policies and programs to address the challenges of water security in a changing climate. One of the earliest of these is the National Water Initiative (NWI), a framework for water reform agreed upon by the federal, state, and territory governments in 2004. The NWI aims to achieve more efficient and sustainable management of water resources by promoting water markets, pricing, planning, accounting, and environmental water provision.
Another very well-known water policy, which is also highly contentious, is the Murray-Darling Basin Plan. This legal instrument sets out the objectives, targets, and rules for managing water resources in the Murray-Darling Basin. This vast water basin crosses multiple states across 3,375 kilometres. The $13 billion plan aims to balance the basin’s environmental, social, and economic needs by setting sustainable diversion limits, environmental watering plans, water quality and salinity objectives, and water trading rules. However, it has not currently delivered its aim. It is fraught with tension: between States, each wanting greater shares of water resources, between agricultural demands and environmental flow needs, and between communities, each fighting for their own economic and environmental survival.
Finally, the National Climate Resilience and Adaptation Strategy outlines the principles and priorities for climate resilience and adaptation in Australia. The strategy identifies water as a critical sector that must adapt to climate change by improving water efficiency, diversifying water sources, enhancing water governance, and protecting water ecosystems. This strategy alludes to the critical problem with Australia’s otherwise well-established response to water issues. Until effective action on carbon emissions reduction is implemented, Australia will continue to suffer increasingly detrimental water extremes and the terrible human and environmental toll that comes with it. As these policies and practice show, Australia has an advanced water management framework and long history of water recycling, reuse, and efficiency. However, water pressures will only continue without a corresponding framework for rapidly reducing carbon emissions.
This Post was submitted by Climate Scorecard Australia Country Manager Robyn Gulliver.