Adelaide
19.4 Delivery to urban water system users

Supporting Information

Overall

The volume reported (125,686 ML) represents potable and recycled water consumption for various uses in the Adelaide region in the 2010–11 year.

Potable water

The volume reported (123,102 ML) represents the volume of potable water supplied for residential, commercial, industrial, municipal and other uses as detailed in the following table.


Potable water consumption itemised by landuse in the 2010–11 year
SA Water land use code National Water Account land use code Potable water consumption (ML)
Residential Residential 82,915
Commercial Commercial 7,213
Industrial Industrial 7,156
Mining Industrial 193
Public institution Municipal 5,869
Public utility Municipal 1,865
Recreational Municipal 2,294
Country lands Other – agriculture 2,147
Primary production Other – agriculture 995
Sundry Remaining other 10,937
Vacant land Remaining other 1,518
Total 123,102

Recycled water

The volume reported (2,584 ML) represents the volume of recycled water produced by wastewater treatment plants (WWTPs) for various uses in the 2010–11 year as detailed in the following table.


Recycled water consumption in the 2010–11 year
Wastewater treatment plant Application Volume (ML)
Aldinga Agriculture irrigation 150
Aldinga and Christies Beach Southern urban reuse project residential use 10
Angaston Agriculture irrigation 27
Bolivar Mawson Lakes municipal use & residential use* 266
Glenelg Adelaide municipal use 1,945
Gumeracha Commercial irrigation 54
Hahndorf Commercial use 1
Myponga Livestock irrigation 35
Victor Harbor
Municipal and agricultural irrigation
96
Total 2,584

* This is what was supplied from Bolivar WWTP to Mawson Lakes. It is then mixed with storm water and potable water, and supplied to residential and municipal uses.

Quantification Approach

Potable water

Data Source

SA Water: Supervisory Control and Data Acquisition (SCADA), geographic information system (GIS) and customer service information system (CSIS) databases.

Provided by

SA Water.

Method

A shapefile of the Adelaide region was used to extract the service point numbers (SPNs) of meters within the Adelaide region from the SA Water GIS database. The SPNs were then used to extract water meter readings for 2010–11 and primary land use codes for each meter from CSIS.

Water consumption was calculated by analysing the difference between consecutive meter readings and summed for 2010–11. To account for meter readings that occurred immediately before or after 2010–11, metered consumption was apportioned based on the following equation:

Vr = ( tr / tm ) × Vm

Where:

Vr = volume for metered period within 2010–11 (kL)
tm = length of period between meter readings (days)
tr = length of metered period within 2010–11 (days)
Vm = volume for metered period (kL).

The primary land use codes were reclassified as residential, commercial/industrial/municipal or other. Then total water consumption for the Adelaide region was calculated by summing the 2010–11 water consumption for each meter based on the 2011 Account land use classes.

Assumptions, Limitations, Caveats and Approximations

  • Apportionment: the method used for apportionment assumes that consumption is constant over the period between meter readings. This may not reflect the actual consumption, which may vary based on seasonal patterns.
  • SPNs: the method assumes that all relevant SPNs have been captured in the GIS accurately and completely.
  • Primary land use: the method assumes that all SPNs have an accurate allocation of primary land use codes and each SPN represents a single land use; however, it is likely that each SPN is providing water for several land uses.

Uncertainty Information

The uncertainty estimate was not quantified.

Recycled water

Data Source

SA Water: wastewater treatment plant (WWTP) records.

Provided by

SA Water.

Method

Measured meter data relating to the volume of recycled water supplied for residential, commercial, industrial, municipal and agricultural/individual irrigation use in the 2010–11 year was obtained from SA Water WWTP records.

Assumptions, Limitations, Caveats and Approximations

  • Item does not include any community wastewater management systems (CWMS) managed by local councils.
  • The volume reported as supply from Bolivar WWTP to Mawson Lakes is the total volume supplied. It is mixed with stormwater and potable water, and supplied to residential and municipal uses.

Uncertainty Information

The uncertainty estimate was not quantified.

Comparative year

This line item was not reported in the 2010 Account. In the 2010 Account, the urban users were included in the regions definition. In the Account 2011, the urban users were excluded from the regions definition. This change was made to allow reporting, in the water accounting statements, on urban water use (as a water asset decrease) and wastewater collection (as a water asset increase), as both were considered useful information to the National Water Account users. Part of this line item was reported at 20.3.2 Application of water from urban water supply system and recycled water supply system for irrigation or outdoor use in the 2010 Account. The comparative year volume has changed because:

  • Reclassification of this line item has occurred. In 2010 only outdoor consumption was reported on; however the 2011 line item includes indoor and outdoor use.
  • The volume reported included recycled water supplied from the Bolivar and Christies Beach WWTPs to the Virginia Pipeline Scheme and the Willunga Basin Water Company respectively. Inclusion of an irrigation scheme in the 2011 Account means that these volumes were reported at line item 19.6 Urban water discharge to irrigation scheme.

Restatement of the value published in the 2010 Account was made as the change was material and increased the accuracy and comparability of the information provided to the users of the National Water Account. The changes and their respective values are detailed in the following table. The restated comparative year volume is 130,509 ML.

Restatement of comparative year information for 19.4 Delivery to urban water system users
2010 Account line item name Potable/recycled water Volume at 30 June 2010 reported in 2010 Account (ML) Value difference to volume reported due to changes (ML) Volume at 30 June 2010 reported in 2011 Account (ML)
20.3.2 Application of water from urban water supply system and recycled water supply system for irrigation or outdoor use Potable water 46,056 81,342 127,398
Recycled water 24,476 (21,365) 3,111
Total 70,532 59,977 130,509