PHYSICAL SUPPLY AND USE
1 The ABS Water Account Australia (WAA) is one of the environmental–economic accounts produced by the ABS based on the System of Environmental–Economic Accounts (SEEA). It consists of supply and use tables (collectively referred to as flow tables) for both physical and monetary volumes.
2 The WAA integrates data from different sources into a consolidated information set making it possible to link physical data on water to economic data, such as those in Australia's National Accounts.
ENVIRONMENTAL ACCOUNTING FRAMEWORK
3 The WAA was developed using the System of Environmental–Economic Accounts (SEEA) and the SEEA–Water. SEEA was first published by the United Nations in 1993 and was elevated to an international statistical standard in 2012. Environmental accounts extend the boundaries of the System of National Accounts (SNA) framework to include environmental resources, which occur outside the economic production and asset boundaries measured by the SNA.
RELATIONSHIP BETWEEN THE WATER ACCOUNT AUSTRALIA AND NATIONAL ACCOUNTS
4 Water supply and use tables provide a framework to link core components of the National Accounts to physical information. Physical data are presented in supply and use tables while some linkages to economic data are also made.
The physical water supply and use tables present aggregates of all available physical data (megalitres) in terms of the supply and use of water within the Australian economy for the financial year 2010–11. The tables illustrate the economic use of water and include: self–extracted, distributed, and regulated discharge (including in–stream use) and reuse.
The WAA presents information on the supply and use of water in the entire Australian economy in both physical and monetary terms.
The WAA includes the entire geographical area of Australia.
The use of saline water (including water from estuaries) for power generation and other industrial uses, although measurable and reported, is not included in the supply and use tables (with the exception of sea water used for desalination) because the scope of the WAA is fresh water only.
Coverage for both supply and use tables includes the following:
- individuals and companies that directly extract water from surface water and groundwater sources for their own use (e.g. domestic, industrial, agricultural or other uses);
- households, government and businesses that use water supplied by water providers for domestic, industrial, agricultural or other uses;
- water providers that extract water from surface water, groundwater and sea water for desalination, and supply it to customers for use (e.g. domestic, industrial, or other use). The majority of water providers are categorised in Water supply, sewerage and drainage services industry (ANZSIC 281) but the Mining, Manufacturing, and Electricity and gas supply industries also supply a small amount of water; and
- water providers that provide reuse water to their customers; other large organisations who treat water and make it available for subsequent reuse; other large organisations who discharge water directly to the environment (e.g. power stations, mines); and major in–stream water users, for example aquaculture and hydro–electricity generation, where this information is available.
Items not covered by the supply and use tables include:
Water consumption and use
- the volume of rainwater used by agricultural crops/pastures that are directly rain fed;
- discharges to the environment resulting from the run–off of irrigation water;
- the reuse/recycling of water on–farm or on–site (i.e. within homes or businesses);
- non–point/diffuse discharges; and
- the impact of storm water infiltration into the sewerage reticulation system.
Calculating water use by industries is not straightforward. Water use can include self–extracted water, distributed water, or reuse water and sometimes a combination of all three sources are used. Calculating water use estimates for an industry or business is made more complicated when water is also supplied to other users, or when water is used in–stream (e.g. for cooling or hydro–power). As such simply adding self–extracted water, distributed water, and reuse water to derive a figure for total water use can be misleading.
In the WAA, volumes of water used and supplied by each industry have been balanced to derive 'water consumption'. This figure takes into account the different characteristics of water supply and use of industries and is a way of standardising water use, allowing for comparisons between industries. As such the following accounting identities have been used:
- Total water use is equal to the sum of Distributed water use, Self–extracted water use and Reuse water use;
- Water consumption is equal to the sum of Distributed water use, Self–extracted water use and Reuse water use less Water supplied to other users and less In–stream use. The use of Distributed water by the environment (Environmental Flows – see paragraphs 34–36), is not included in total water consumption.
For most industries, water use and water consumption are the same as most industries do not have any in–stream use or supply water to other users. However, water consumption and use will vary considerably for some industries, specifically the Water supply, sewerage and drainage services industry, Electricity and gas supply industry and Mining industry, where in–stream water use and water supply volumes are significant.
There are a variety of water sources that may be supplied as reuse water, including waste water (from sewerage systems), drainage water, storm water or other water providers (i.e. a 'bulk' reuse water supply). Sewerage systems collect and treat waste water which may be treated to primary, secondary or tertiary levels. Storm water may also be collected using infrastructure separate to sewerage systems and, depending upon its intended use, may or may not be treated before being supplied as reuse water. Drainage water is also collected in regional collection drains managed by irrigation/rural water providers. This water may be supplied as reuse water to customers or discharged to the environment. This process is analogous to urban reuse systems, however the water is typically treated in urban systems before it is supplied.
The water discharged from the economy to the environment may be regulated or unregulated. Regulated discharge refers to water discharged after use where that discharge does not match the natural flow regime of the receiving water body. For example, the waste water discharged by sewerage service providers is a regulated discharge. The water discharged by the Electricity and gas supply industry after use in hydro–electric power generation is also regulated discharge.
The water discharged by households and other industries to sewerage or drainage systems, however, is not a regulated discharge as the water is not discharged directly to the environment. This does, however, become a regulated discharge, after it has been treated by the Sewerage industry and released back to the environment. Discharges from non–point sources, such as those from the Agriculture industry (e.g. run–off from irrigation), are not included in this publication and are represented in the supply and use tables as "not available".
Regulated discharges in the physical supply and use tables include Environmental Flows (see paragraphs 34–36).
Data for this release are sourced from a range of ABS surveys as well as State, Territory and Local Government agencies, water authorities and industry organisations. The main sources are listed below.
- 2010–11 Water Supply and Sewerage Services Survey (WSSS)
- 2010–11 Agricultural Census (AGC)
- 2008–09 Electricity Generators Survey (EGS)
- 2008–09 Energy, Water and Environment Survey (EWES)
Note that data from the latter two surveys listed above did not feed directly into the 2010–11 WAA but were used to assist in modelling water use for 2010–11.
State and Territory government agencies and major businesses (including major state/territory water corporations):
- The 2010–11 NSW Water Supply and Sewerage Benchmarking Report (NSW Office of Water).
- Queensland Statewide Water Information Management (SWIM) under arrangements with the Queensland Water Directorate (QWD).
- The Department of Water, the Economic Regulatory Authority and major water corporations (Western Australia).
Surveys conducted by other government agencies, industry associations, and annual reports of water providers:
- National Water Commission (NWC) and Water Services Association Australia (WSAA) 2010–11 National Performance Report – Urban Water Utilities.
- National Water Commission (NWC) National Performance Report 2010–11: Rural Water Service Providers.
- Annual/environmental reports for 2010–11 from major water providers.
Revisions have been applied to 2009–10 physical water supply and use tables as a result of revised data from ABS surveys.
For 2010–11, financial questions were included for the first time on the ABS Water Supply and Sewerage Services Survey (WSSS) and Economic Activity Survey (EAS), leading to changes in the methodology for producing Monetary supply and use estimates and revisions to 2008–09 and 2009–10 estimates.
Revisions to the treatment of Environmental Flows data are described in paragraphs 34–36.
Methods for Calculating Water Supply and Use
These notes are intended as a general guide to the method of calculating estimates of water supply and use. For more detail on the methods please contact the Director, Environmental Accounts Section, Australian Bureau of Statistics.
A complete list of water providers in 2010–11 was compiled using the ABS Business Register (ABSBR) supplemented by additional information supplied by State and Territory regulatory departments, industry bodies, and other water data providers. All water providers identified were surveyed in the ABS 2010–11 Water Supply and Sewerage Services Survey.
Water providers provided information on:
- Volume of water extracted from the environment and/or the volume of water received from other water providers (this information was used to reconcile total supplies and to avoid double counting of water volumes).
- Volumes of water supplied to particular industries (e.g. Agriculture, Mining and Manufacturing) and for household use. This information was reconciled with water use as reported by water users. It also enabled the calculation of coefficients (e.g. ML/employee) for industries for which there was little or no data on water use.
- The amount of water used by the water supply organisation (including mains flushing and water used on parks and gardens operated by councils that supplied water).
- Volume of water lost from the supply system (including customer meter errors and system water losses).
- Volume of water discharged by location.
- Volumes of reuse water supplied to particular industries (e.g. Agriculture, Mining and Manufacturing) and for household use. Water reuse volumes were not imputed where water providers did not provide reuse water volumes.
- Distributed water supplied to households and the number of connections served by water supply and sewerage services. Where information was not available for distributed water supplied to households, neighbouring or matched Local Government Area (LGA) coefficients based on average megalitre use per connection were used.
- The amount of water released for environmental flows. This only includes those environmental flows released in accordance with a specific plan prepared in conjunction and/or approved by the appropriate environmental (resource) regulator (see paragraphs 34–36).
- Distributed water use was the amount supplied to the Agriculture industry by water providers.
- Total water consumption by Agriculture was sourced from the 2010–11 Agricultural Census. Generally, the amount of distributed and reuse water consumed (collected on the ABS 2010–11 Water Supply and Sewerage Services Survey) was subtracted from total water consumed; the remainder was assumed to be self–extracted water. Note that self–extracted water for the Agriculture industry includes all groundwater that is extracted by Agriculture businesses.
- Reuse water usage includes water used from regional reuse schemes.
- Data for Victoria were confronted against Victorian Water Register (Department of Sustainability and Environment, State Government Victoria, 2011).
- The physical supply and use tables present an industry view of Agriculture. The Agriculture industry view presents only the agricultural activity that occurs in businesses where the primary income producing activity (i.e. the activity with value added that exceeds the value added of any other activity carried out by the same business) of the business is agricultural production. Businesses which undertake some agricultural activity but for which other activities provide most of the income are excluded from the Agriculture industry view. For example, a business which generates most of its income from transporting agricultural produce, but also grows some agricultural commodities would be classified to the Transport, postal and warehousing industry. The agricultural production is still counted but is attributed to the Transport, postal and warehousing industry. As such the industry view of Agriculture shows a lower level (approximately 5%) of water consumption than the agricultural activity view.
- Note that the ABS publication Water Use on Australian Farms, 2010–11 (ABS cat. no. 4618.0) presents an activity view of agriculture – therefore its total consumption estimates are slightly different to the industry estimates presented in the physical water supply and use tables in the 2010–11 WAA.
For Mining and Manufacturing:
- Estimated water use was modelled using benchmarked data from 2008–09 EWES and 2010–11 Business Activity Statement Unit Record Estimates (BURE).
- Estimates for in–stream water use and water discharges were modelled using 2009–10 WAA data.
- Mine dewatering is categorised as self–extracted in–stream (non–consumptive) use by the Mining industry. The water is usually used on–site or subsequently discharged to the environment.
- Only division level estimates are published at the State/Territory level (sub–division splits are presented at the National level) due to lack of survey input data for the Mining and Manufacturing industries. In editions of WAA prior to 2009–10, estimates for ANZSIC sub–division splits were published for Mining and Manufacturing for all states, however the modelled data which formed the basis of the 2009–10 and 2010–11 estimates were deemed not sufficiently reliable for publication at the sub–division level.
For Electricity and gas supply:
- For the 2004–05 and 2008–09 editions of WAA, data for water use by electricity generators were sourced from the ABS Electricity Generators Survey of Water Use (a census of all energy producers with a greater than 10 MW capacity), however this survey was not run in reference to 2010–11, so these data were modelled using administrative data from annual reports, websites and the National Greenhouse Energy Reporting System (NGERS).
For "Other" industries (includes construction, service industries, government, education, health, arts and recreation – see Glossary
for list of industries):
- Physical water use was modelled based on benchmarked data from 2008–09 EWES and data from the Business Activity Statement Unit Record Estimates (BURE). Estimates of ANZSIC divisions O to R were derived using employee based coefficients derived from external data plus other administrative sources.
- Data on bore water use for parks and gardens in Western Australia were provided by Western Australia's Department of Water.
For household water use:
- Distributed and reuse water use was the amount supplied to households by water providers (these data were sourced mainly from the ABS 2010–11 Water Supply and Sewerage Services Survey.)
- Self–extracted water use by households was calculated by applying average state "volume (kL) per connection" coefficients and applying these to the households known not to be served by water providers (estimated by subtracting the connections served by water providers from the total number of households in each State and Territory). Data on domestic bore water use in Western Australia was provided by WA Department of Water. Note that self–extracted water use estimates for households do not include rainwater tank usage for households connected to mains supply.
Water use modelling:
- ABS conducts a detailed energy and water use survey every three years for the Mining, Manufacturing, Construction, Electricity Generation and the service industries. This survey (the Energy, Water and Environment Survey, or EWES) was conducted for the 2008–09 reference year, with the results feeding directly into the 2008–09 edition of WAA. The survey will be conducted again for the 2011–12 reference year. Water use by these industries has been modelled in this 2010–11 edition of WAA. Note that the water use estimates for households and agriculture are still conducted on the basis of annual surveys.
- The water use modelling incorporated reported water use information from the 2008–09 EWES and corresponding industry output information from Business Activity Statement Unit Record Estimates (BURE). The relationship between water as a production input and industry output is identified from these 2008–09 survey results and applied to BURE. This structural relationship is assumed constant between years, meaning that the efficiency of water use is assumed to be the same between 2008–09 and these modelled water use estimates for 2010–11. Changes in water use efficiency will be identified when updated survey information becomes available for the 2011–12 reference year.
Key Commonwealth, State and Territory water agencies recognise two forms of water used for Environmental Flows:
- Planned (rules–based) environmental water relates to statutory requirements to maintain specific water regimes (e.g. particular levels, flow rates, aquifer pressures).
- Held (entitlement–based) environmental water relates to specific entitlements, which accrue annual allocations of water that can be extracted (or left in–stream) for environmental purposes.
It is apparent that some water utilities do not measure all Environmental Flows and there is subsequent uncertainty around the level estimates. In the 2008–09 and 2009–10 editions of WAA Environmental Flows were not separately identified in the physical supply and use tables. The Environmental Flows that were reported in surveys were presented within the estimates for distributed, reuse and in–stream water supplied and used by the Water supply, sewerage and drainage services and Electricity and gas supply industries. Consumption for these industries was not affected by this treatment of Environmental Flows volumes (i.e. these flows were defined as non–consumptive use).
Due to the uncertainty in the estimates, in the 2010–11 edition of the WAA the Environmental Flows that were reported in surveys are presented only within the regulated discharge estimates for the Water supply, sewerage and drainage services and Electricity and gas supply industries. The Environmental Flows were not presented within the estimates for distributed, reuse and in–stream water supplied and used. This edition of the WAA presents revised 2009–10 estimates reflecting this change.
Data Quality and Reliability
Water Accounts for Australia estimates are prepared from a wide range of statistical sources. Some are closely related to the environmental accounting framework, but others are not completely aligned in various respects, including coverage, concepts and timing. Most of the basic data are derived from statistical surveys or as a by–product of government administrative processes. The frequency, detail and timeliness of these data sources are constrained by many factors, including available resources and meeting the administrative requirements of government. Any improvement in timeliness of data is usually at the expense of detail, reliability or additional resources. Therefore, estimates may be subject to modelling to fill some of the gaps from surveys or administrative collections.
The majority of water supply data is collected by the ABS and is coherent with other data sources. The majority of water use is collected by the ABS, with the following exceptions:
MONETARY SUPPLY AND USE
- Aquaculture, Forestry and logging, Fishing, hunting and trapping and Agriculture services were modelled from economic data collected in 2008–09 Energy Water Environment Survey.
- Electricity and gas supply estimates were modelled using administrative data from annual reports, websites and the National Greenhouse Energy Reporting System (NGERS). (see paragraph 30).
- Mining and Manufacturing industry estimates at the State/Territory level were modelled from economic data collected in 2008–09 Energy Water and Environment Survey and data from Business Unit Registry Estimates.
- "Other" industry estimates were modelled from economic data collected in 2008–09 Energy, Water and Environment Survey and data from Business Unit Registry Estimates. For some "other" industries only a limited amount of survey data were available and estimates were mostly based on coefficients of water use (see paragraph 31).
- For households, self–extracted water use was based on coefficients of water use (see paragraph 32).
The Monetary supply and use section presents aggregates of all available quantitative monetary data (dollars) in terms of the supply and use of water within the Australian economy for the financial year 2010–11. Supply and use tables illustrate the economic transactions associated with the use of water and the provisions of sewerage, waste water and drainage services (also referred to as water related services).
The monetary section covers:
- supply of distributed water and water related services in the economy by the Water supply, sewerage and drainage services, Mining, Manufacturing, and Electricity and gas supply industries;
- expenditure on water and water related services by industries, households and governments; and
- value added to the economy by the major water–using industries.
The scope is limited to distributed water, reuse water and waste water, sewerage and drainage services. Distributed water is further subdivided into:
- urban distributed water
- rural distributed water
- bulk water (both urban and rural).
Rural distributed water is water supplied via mains, open channels or natural water ways, carted untreated water/treated effluent supplied by water suppliers (including industries other than the Water supply, sewerage and drainage services industry) for irrigation and other rural use by the agriculture industry. Urban distributed water is water supplied by water suppliers via mains water systems for non–agriculture use.
The scope is also limited to "net distributed water" which, in this context, is defined as water that has been supplied from one economic unit to another for a fee, creating a measurable economic transaction. The net distributed water excludes distribution losses and supply to the environment for which there is no matching economic transaction.
For national and environmental accounting purposes the Water supply industry is considered to provide the service of 'water delivery' rather than being the seller of a product (water).
Monetary data for the supply (sales) of distributed water and monetary data for the use (purchase) of distributed water by industries, governments and households have been integrated during the compilation process. This requires some adjustments to input data to ensure consistency of information in the WAA.
It is difficult to separately identify the revenue from reuse water with that from distributed mains supply and estimates on revenue and expenditure on distributed water also include transactions associated with reuse water.
Many businesses and households use self–extracted water for their own use, such as farms for irrigation or hydro power plants to generate electricity. Estimates for the value of self–extracted water have not been included in this section due to lack of reliable data.
Data presented in this section are drawn from a variety of sources including those used in the Physical water supply and use section. In addition to these sources, the following ABS data were used:
Administrative data were also sourced from:
Methods for Calculating Monetary Supply and Use
- Water suppliers' annual financial reports
- Public administration and finance data
The data collected from these sources were collated and aggregated to State and Territory level.
Industry gross value added:
- Expenditure on distributed water was calculated by taking total volume and connected properties reported by each water utility, calculating average consumption values per household and applying the utility's fixed and variable tariff structures to these average values. Where tariff information is not available, an average water rate ($/kL) was applied to the volume of water consumed by the households within those service areas. This methodology has been applied to the 2008–09 and 2009–10 household expenditure estimates, resulting in revisions to the estimates at the national level by – 4% for 2008–09 and by +1% for 2009–10.
- Government expenditure and social transfers in kind monetary data were obtained from ABS Australian System of National Accounts, 2010–11 (unpublished data).
- Revenue and expenditure on water and related services for the water supply industries were included in the 2010–11 WSSS for the first time and was supplemented by administrative data. Information on expenditure on water and related services by other industries was sourced from the 2010–11 Economic Activity Survey. The estimates for 2008–09 and 2009–10 have been revised and the scope of urban and rural distributed water has changed slightly (see paragraph 42).
Data Quality and Reliability
- Water intensity can be expressed as the amount of industrial output produced from a corresponding unit of water used in the production process. This is expressed in the monetary tables as industry gross value added ($ millions) per GL of water used. Comparisons between industries and changes over time in the average gross value added per GL of water use is complicated by the impact of prices, particularly for Agriculture and Mining, where commodity prices can vary substantially from year to year. This is relevant for analyses of incomes (current prices) generated per GL of water consumed in a given year. For this reason, the percentage change movements in industry gross value added per GL of water consumed between 2009–10 and 2010–11 have been calculated using chain volume measures of industry gross value added. It should also be noted that the data represent industry averages. Changes over time in the mix of commodities produced by a broad level industry such as Agriculture, Mining or Manufacturing could result in significant changes in the water intensity.
The total revenue from sales of water and water related services by the Water supply, sewerage and drainage services industry (i.e. the supply side estimates) were coherent with Australian Industry, National Accounts Supply table and National Water Commission National Performance Report (NPR) data.
Water use estimates for households, industries and governments were based on several ABS surveys and National Accounts data. Expenditure estimates and annual movements for final consumption by households and intermediate industries are in line with modelled results using the physical water volume and CPI data, and supply/revenue estimates. Expenditure for the agriculture industry was not collected on the 2010–11 Agricultural Census form and were modelled from physical water volumes and water supply revenue estimates.
GROSS VALUE OF IRRIGATED AGRICULTURAL PRODUCTION
The Gross Value of Irrigated Agricultural Production (GVIAP) was estimated using data from the ABS 2010–11 Agricultural Census (see Agricultural Commodities, 2010–11, Australia
(ABS cat. no. 7121.0), and Water Use on Australian Farms
(ABS cat. no. 4618.0), as well as other ABS collections and administrative data used to calculate the value of agricultural commodities produced (see Value of Principal Agricultural Commodities Produced, 2010–11, Australia
, (ABS cat. no. 7503.0)).
Method of Calculation
The ABS methodology for calculating GVIAP is described in the information paper Methods of estimating the Gross Value of Irrigated Agricultural Production
(ABS cat. no. 4610.0.55.006).