South East Queensland
19.4 Delivery to urban water system users

Supporting information

a. Overview

The volumetric value for the line item at the end of the 2011–12 year was 259,039 ML.

This line item consists of all potable, non-potable and recycled water delivered to consumers within the South East Queensland (SEQ) region by the urban water supply system and the recycled water supply system. This includes residential, commercial, industrial, municipal and other consumers. It includes both consumers supplied by urban utilities as part of the SEQ water grid and also consumers supplied off-grid.


Potable, non-potable and recycled water delivered to consumers
Purpose

Volume (ML)

 

Potable

Non-Potable

Recycled

Residential use

178801

297

Commercial, industrial, municipal use

54274

10,328

Agricultural / individual irrigation use    

751

Other use – urban use

3374

   
Recycled water on-site outdoor / irrigation use    

Recycled water on-site in-door use      
Recycled water on-site within process use (no–recirculation)    

7551

Other use – specific (supply to Swanbank power station)     3,663
Total

236,449

22,590

 

Notes: Where data were not available this has been indicated with (–).

b. Water supply to users from the urban water supply system

SEQ's urban water system comprises three sub-components: 

  • Urban water supply system
  • Wastewater system
  • Recycled water system

The water supplied to the urban water supply system came from four sources: surface water (216,735 ML), groundwater (149 ML), desalinated water (3,427 ML) and imported water (22,902 ML).

Almost 92% of the urban water consumption delivered to urban water users during the 2011–12 year came from surface and groundwater components (216,884 ML) of the urban water supply system.  The rest was met up from desalinated water and exported water.

During the 2011–12 year, approximately 89% of the urban water supply system outflow was water supply to urban users (236,449 ML). Approximately 11% of the urban water was leaked to groundwater storages (19.3). There was no loss to surface water and operational losses was nil.

The following figure shows all the inflows and outflows associated with the urban water supply system. For more detail on a particular flow associated with the urban water supply system, refer to the line item notes. 


Schematic diagram of water inflows and outflows during the 2011–12 year for SEQ's urban water supply system; Line item numbers are provided in brackets.
Schematic diagram of water inflows and outflows during the 2011–12 year for SEQ's urban water supply system; Line item numbers are provided in brackets.

 

c. Water supply to users from the recycled water system

More than 6% of urban water consumption came from the recycled water system (15,039 ML).  

During the 2011–12 year, approximately 61% of the recycled water produced was delivered to urban users. Approximately 31% of the recycled water was used on-site at wastewater treatment plants throughout the region; the remaining 8% was exported to  the Tarong power station (part of 19.11).  The following figure shows all the inflows and outflows associated with the recycled water system. 

For more detail on a particular flow associated with the recycled water system, refer to the line item notes. Note that volumes annotated with a * indicate flows between sub-components and are not reported in the account. As such, these flows do not have an associated line item number.


Schematic diagram of water inflows and outflows during the 2011–12 year fro SEQ's recycled water system; Line item numbers are provided in brackets.
Schematic diagram of water inflows and outflows during the 2011–12 year fro SEQ's recycled water system; Line item numbers are provided in brackets.


 * due to data discrepancies, it was assumed that inflow into recycled system equalled to the recycled water usage.

 

Quantification approach

Data source

Seqwater WaterHub database, this information was previously provided by DERM but commencing with the 2012 Account, it has since been provided by Seqwater.

Qldwater: Statewide Water Information Management (SWIM) system indicator WA20 (residential recycled water use), WA21 (commercial, industrial and municipal recycled water use) and WA22 (agricultural use) for Queensland Urban Utilities and Unitywater recycled water data.

Recycled water data from Gold Coast, Redland and Logan city councils.


 

Provided by

Bureau of Meteorology.

Method

Department of Energy and Water Supply (DEWS) provided residential, commercial/industrial/municipal and other metered potable water consumption data for the SEQ Water Grid. Off–grid consumption was assumed to be equal to the off–grid diversions provided in line item 11.2 Non–allocated diversion of surface water. The off – grid consumption was divided into the land use categories using the consumption percentage obtained from the SEQ water grid data.

Recycled water consumption

Queensland SWIM system data was used to estimate residential, commercial/industrial/municipal and agricultural consumption data for Queensland Urban Utilities and Unitywater. Only consumption within the Caboolture, Pine Rivers and Redcliffe council areas was included for Unitywater.

Gold Coast, Redland and Logan City councils provided recycled water consumption for the same land use categories.

DEWS provided the metered volume of recycled water provided to the Swanbank power station via the Western Corridor Recycled Water Scheme. 

Assumptions, limitations, caveats and approximations

  • Data on non-potable water consumption was not available. If non-potable water is provided by urban utilities to consumers, this volume would be minor in comparison to the potable water supplied.

  • Moreton Bay Regional Council incorporates the previous Councils of Caboolture, Pine Rivers and Redcliffe. The council's boundary does not match the SEQ region boundary exactly and as such a slight over estimate of the recycled water consumption within the region may have occurred.

Uncertainty information

Ungraded.

Comparative year

This line item corresponds partly to line item '19.4 Delivery to urban water system users' reported in the 2011 Account.