Trends in water use information from across Australia are important because of long-term variability in rainfall and runoff across Australia as well as the reduced water availability over the past 10 years.
For AWR 2005, water use information is presented at the national scale, through outputs from the Water Account, Australia, 2004-05, and at the water management area scale for 168 areas where water use was estimated. Information was also collated for water access entitlements, allocations and water trading in Australia for the 2004-05 reporting period.
The Discovery Phase for the Water Use theme identified the types of available information on water use at a state, territory and national level and how these could be drawn together to provide a national assessment. A number of existing programmes could be modified to meet the needs and timeframes of AWR 2005, these included:
- Water Account, Australia, 2004–05: uses datasets collected by the Australian Bureau of Statistics and the states and territories and synthesises them into a national database to provide a comprehensive, nationally comparable snapshot of Australia’s water use. This project was fast-tracked through additional funding through AWR 2005.
- Experimental Estimates of Regional Water Use, Australia, 2004–05: provides details on water use information at a regional scale for selected water management areas across Australia. These data have been compiled through a modelling approach, where the actual enterprise types have been aggregated according to their industry and according to where they are spatially located.
- Water Access Entitlements, Allocation and Trading, 2004–05: presents data on the number of water access entitlements, the volume of water allocated to water access entitlements, and water trading in Australia in 2004-05.
- Water Use on Australian Farms, 2004-05: provides data on the volume of water used for irrigation by crop type and area at a state and territory and national scale.
The Water Account, Australia, 2004-05 and other ABS reports are available on the
Publications page, or via the Australian Bureau of Statistics website.
Water use can be interpreted in a number of ways and the term is often used interchangeably with water diversion and water extraction, which have been used as proxies for water use. Here, as in the Australian Bureau of Statistics water account, water use is separated into three components—self-extracted, distributed, and reuse water:
- self-extracted water is defined as water extracted directly from the environment for use, and includes water from rivers, lakes, farm dams, groundwater and other water bodies
- distributed water is water supplied to a user, often through a non-natural network (piped or open channel), and where an economic transaction has occurred for the exchange of this water. Water supplied by irrigation water providers through natural waterways and bores falls under the definition of distributed water
- reuse water refers to wastewater that may have been treated to some extent, and then used again without first being discharged to the environment. It excludes water that is reused onsite, for example on-farm water reuse or water being constantly recycled within a manufacturing plant.
Key findings – water use
Australia’s water use
- During 2004–05, 79,784 gigalitres of water was extracted from the environment and used within the economy. Of this amount 11,337 gigalitres was extracted by water providers, and water users directly extracted 68,447 gigalitres.
- Of the total volume extracted from the environment, 62,455 gigalitres was returned to the environment as regulated discharge, with 60,436 gigalitres of this discharge used almost entirely for in-stream use by hydropower generators.
Water used across the economy
- The consumptive water use in 2004-05 was 18,767 gigalitres. The sectors of the economy that used this water were:
- agriculture – 65 per cent (12,191 gigalitres)
- household – 11 per cent (2,108 gigalitres )
- water supply industry – 11 per cent (2,083 gigalitres)
- other industries – 6 per cent (1,059 gigalitres)
- manufacturing – 3 per cent (589 gigalitres)
- mining – 2 per cent (413 gigalitres), and
- electricity and gas -1 per cent (271 gigalitres).
- Consumptive use of water in 2004-05 represented 22 per cent of the storage capacity of large dams and 47 per cent of the volume in storage at 30th June, 2005.
- In 2004–05, Australian agriculture used 12,191 gigalitres of water for agricultural production, a 19 per cent reduction from that used in 2000-01 (14,989 gigalitres). This reduction is primarily the result of reduced water availability.
Trends in water use
- The water accounts have shown that water consumption for 2004–05 was 18,767 gigalitres, which was lower than the 21,703 gigalitres consumed in 2000–01. This was a 14 per cent decrease in water used across Australia, which is consistent with the reductions in total inflows across a similar period.
- The reduction in water consumption from 2000–01 to 2004–05 primarily resulted from the reduction in agricultural use from 14,989 gigalitres to 12,191 gigalitres, due to reduced water availability
- Water consumption for rice production has declined by 72 per cent (2223 gigalitres in 2000–01; 631 gigalitres in 2004–05). Water consumption for cotton production declined by 37 per cent (2896 gigalitres in 2000–01; 1822 gigalitres in 2004–05).
- Household water use decreased by 8 per cent from 2278 gigalitres in 2000-01 to 2108 gigalitres in 2004-05. Sixteen per cent of households were reusing or recycling household water, representing a significant increase from 11 per cent in 2000–01.
- Water used by the mining industry increased 28 per cent from 321 gigalitres in 2000–01 to 413 gigalitres in 2004–05, largely due to increased mining activity in Western Australia (69 gigalitres increase).
In 2004-05 a total of 32 gigalitres was recycled from Melbourne Water’s Western Treatment Plant at Werribee. Of this volume, about two thirds was used to irrigate pasture within the boundaries of the treatment plant.
Image by Robert Molloy, sourced from SKM
Reuse of water
- Reuse water made up 425 gigalitres of total water supplied by water providers in 2004–05.
- While still a very small amount, there was a tenfold increase in the use of reuse water provided by water suppliers and used by households from 0.167 gigalitres in 2000-2001 to 1.767 gigalitres in 2004-2005.
Distribution of water use
- The highest rates of water consumption, when compared to total inflows, were in Victoria (23 per cent), New South Wales (13 per cent), South Australia (32 per cent) and the Australian Capital Territory (22 per cent). Queensland, Western Australia, Northern Territory and Tasmania had much lower proportions of consumptive use in relation to total available water.
- The higher proportions of water use in relation to availability for New South Wales, Victoria and South Australia is a result of the large investments in water delivery systems and irrigation infrastructure and from the development of agricultural land in these areas.
- Despite having only 6 per cent of Australia’s total runoff, more than 50 per cent of Australia’s water use occurred in the Murray-Darling Basin.
- The higher levels of use in the Murray-Darling Basin and in south-eastern Australia, south-east Queensland and south-west Western Australia were apparent from this assessment. The top 20 modelled areas comprised approximately 75 per cent of the consumptive water use across Australia. Based on regional water use estimates, the three highest water-using regions were the Murrumbidgee; Broken, Goulburn and Campaspe; and Murray water management areas.
Water entitlements and trading
- The entitlement volume of water access entitlements was 29,831 gigalitres in 2004–05.
- A total of 1300 gigalitres of water was traded in 2004–05, with 1053 gigalitres as temporary trades and the remainder (248 gigalitres) permanent trades. Of this volume 86.9 gigalitres was traded between states, comprising 5.2 gigalitres of permanent interstate trade and 81.7 gigalitres of temporary interstate trade (ABS 2006d).
Water use is discussed in more detail in the following sections: