South East Queensland
19.20 Other urban water system decreases

The volume for the line item during the 2012–13 year was 7,217 ML.

The volume represents the sum of the following three components:

• remaining non-revenue water from urban water supply system (non-revenue water other than the real losses):   5,653 ML
• losses from wastewater treatment system: 1,522 ML
• losses from advanced water treatment: 42 ML.
  

The volume does not include leakage to groundwater or losses to the landscape, including pipe bursts from potable water supplies (real losses component of non-revenue water included in line item 19.3 Leakage to groundwater). 

South East Queensland' (SEQ) urban water system comprises three sub-components: 

• urban water supply system
• wastewater system
• recycled water system.

There are four main sources of water for SEQ's urban water supply system:

• surface water (11.2 and 11.12 )
• groundwater (11.3)
• desalinated water (11.6)
• imported water (11.5). 

The water intake to the urban water supply system (251,897 ML) is from four sources: surface water (224,420 ML), groundwater (158 ML), desalinated water (2,805 ML), and imported water (24,514 ML).

During the 2012–13 year, the volume of water delivered to urban users (potable and non-potable water supplied amounting to 219,392 ML) was the major outflow from the urban water supply system. This supply for urban consumption represented about 87% of the total outflow. Approximately 11% of the outflow was leakage (19.3 Urban water system leakage to groundwater) and 2% was remaining losses.

Schematic diagram of water inflows and outflows during the 2012–13 year for South East Queensland'  urban water supply system; line item numbers are provided in brackets

The volume of wastewater collected by the wastewater system during the 2012–13 year (11.4 Wastewater collected) was 244,668 ML.  The majority of the outflow from the wastewater system (74%) was treated wastewater discharged to sea (19.7 Wastewater discharge outside of region); approximately 16% was discharged to surface water (19.5 Urban water discharge to surface water); and approximately 9 % was recycled. The remainder (1%) comprised a small volume of treated wastewater discharged to landscape and losses.

The following figure shows all the inflows and outflows associated with the wastewater system. There was some unaccounted flow in the wastewater system that produced an error of  0.4% of total wastewater system inflows. 

For more detail on a particular flow associated with the recycled water system, refer to the line item notes. Note that volumes annotated with an asterisk (*) 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 2012-13 year for South East Queensland's wastewater system; line numbers are provided in brackets

Approximately 7% of urban water consumption (236,941 ML) came from the recycled water system and from advanced water treatment.

During the 2012–13 year, approximately 55% of the recycled water produced (23,241 ML) was supplied to urban users. Approximately 13% of the recycled water was used on-site at wastewater treatment plants throughout the region; approximately 20% was used in-process (recirculated); and the rest was delivered for advanced water treatment. There was some unaccounted flow in the recycled water system inflows that produced an error of (1%) of total recycled water supply system inflows.The following figure shows all the inflows and outflows associated with the recycled water system and advanced water treatment.

For more detail on a particular flow associated with the recycled water system and advanced water treatment, refer to the line item notes. Note that volumes annotated with an asterisk (*) 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 2012–13 year for South east Queensland'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.

Seqwater: WaterHub database;

Queensland Urban Utilities (QUU), Logan City Council, Toowoomba Regional Council: datasheets via Queensland Water Directorate (Qldwater);

Council of the City of Gold Coast: SWIM code data

South Burnett Regional Council: datasheet

Council of the City of Gold Coast; Logan City Council; QUU; Seqwater; South Burnett Regional Council; Toowoomba Regional Council.

Losses from the urban water supply system reported as part of this line item is the volume of remaining non-revenue water.  Non-revenue water is generally calculated as water supplied to users less metered and billed domestic and non-domestic water consumption. Non-revenue water may be broken into four components: authorised unbilled, apparent losses (unauthorised), apparent losses (metering), and reals losses (bursts, leaks and background losses).The volume presented as remaining non-revenue water was calculated by subtracting real losses from the total non-revenue water.

Losses from the wastewater system reported as part of this line item were identified as part of the wastewater system analysis as discussed and agreed with the water authorities.

Losses from the advanced water treatment are the volume of recycled water transferred for advanced water treatment from QUU and the volume received by Seqwater.

Not quantified.