Adelaide

20.3.2 Application of water from urban water supply system and recycled water supply system for irrigation or outdoor use

Supporting information

The volume reported in the water accounting statement (70,532 ML) represents irrigation and other outdoor activities using:

potable water from SA Water’s urban water supply system
recycled water from SA Water’s wastewater treatment plants (WWTPs).

The volume of water from each system used for irrigation during 2009–10 is presented in the table below.

System	Volume (ML)
SA Water potable system	46,056
SA Water recycled system	24,476
Total	70,532

The volume of potable water used for irrigation and other outdoor activities during 2009–10 is presented in the table below.

Outdoor activity	Volume (ML)
Irrigation
Country lands	2,767
Household garden watering	34,383
Primary production	1,536
Public institution	2,667
Public utility	1,230
Recreation	2,726
Vacant land	591
Other
Mining	156
Total	46,056

The volume of recycled water from WWTPs that was used for irrigation and other outdoor activities during 2009–10 is shown in the table below.

Wastewater treatment plant	Volume (ML)
Aldinga	328
Angaston	80
Bird-in-Hand	139
Bolivar	18,073
Christies Beach	3,525
Glenelg	2,134
Gumeracha	49
Hahndorf	4
Myponga	2
Victor Harbor	142
Total	24,476

Quantification approach

Data source

SA Water: Supervisory Control And Data Acquisition (SCADA), Geographic Information System (GIS), Customer Service Information System (CSIS) and private Wastewater Treatment Plant (WWTP) databases.

Data provider

SA Water.

Method

Irrigation from water supply system

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 used to extract readings for individual water meters from the SA Water CSIS database for 2009–10.

Water consumption was calculated by analysing the difference between consecutive meter readings and summed for 2009–10. To account for meter readings that occurred immediately before or after 2009–10, metered consumption was apportioned based on the following equation:

V_r = ( t_r / t_m ) × V_m

where:

V_m = volume for metered period (kL)

V_r = volume for metered period within the reporting year (kL)

t_m = length of period between meter readings (days)

t_r = length of metered period within reporting year (days).

The volume of potable water used for irrigation and other related activities was estimated based on the primary land use code for each meter. The assumed proportion for irrigation and other outdoor activities is summarised by land use in the table below.

Land use	Percentage used for irrigation and other outdoor activities
Commercial	0
Country lands	100
Industrial	0
Mining	100
Primary production	100
Public institution	40
Public utility	100
Recreational	100
Residential	40
Sundry	0
Vacant land	40

Source: OWS & DFW 2010

Irrigation from recycled water system

SA Water manages several WWTPs that produce recycled water for irrigation, specifically:

Aldinga
Angaston
Bird-in-Hand
Bolivar, excluding residential use at Mawson Lakes
Christies Beach, including some via an Aquifer Storage and Recovery scheme
Glenelg
Gumeracha
Hahndorf
Myponga
Victor Harbor.

Recycled water volumes were extracted from a private database held by SA Water for these WWTPs.

Uncertainty

Uncertainty is +/-10% based on meter calibration.

Assumptions, approximations and caveats/limitations

This item does not include any recycled water produced by community waste management schemes, including the Port Elliot WWTP, that are managed by local councils, or other private schemes that are run by companies such as North Para Environmental Control Pty Ltd and the Willunga Basin Water Company.