19.11 Transfer of water outside of region
a. Transfer of water outside of region
The Barossa, Onkaparinga Summit Storage and Myponga water treatment plants (WTPs), located within the Adelaide region, supply potable water to customers outside the region. The following table summarises the volume (3,739 ML) of potable water exported during the 2011–12 year.
|Water treatment plant||Volume (ML)|
|Summit Storage (Onkaparinga)
b. Urban water system overview
The urban water supply system is one of three sub-components of Adelaide's urban water system. The three sub-components are the:
- urban water supply system
- wastewater system
- recycled water system.
During the 2011–12 year, the majority (66%) of Adelaide's urban water was sourced from catchments within the region (line item 11.2). Imported River Murray (line item 11.9) water constituted approximately 31% of the urban water supply system's source water. Also, during the 2011–12 year, the Adelaide desalination plant commenced operating and made up the remaining 3% of Adelaide's urban water sources (line item 11.6).
Urban potable water consumption (line item 19.4) was 127,729 ML during the 2011–12 year, representing 84% of all outflows from the urban water supply system. A very small volume of water (2%) was transferred out of the region via normal operations in SA Water's service area (line item 19.11). Non-revenue water, including pipes bursting and background leakage (line item 19.3) and other losses (line item 19.20), made up the remaining urban water supply system outflows.
The following figure shows all the inflows and outflows for 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 for Adelaide's urban water supply system during the 2011–12 year; line item numbers are provided in brackets
SA Water: Supervisory Control And Data Acquisition (SCADA) and customer service information system (CSIS) databases.
Geographic information system (GIS) analysis was used to extract the service point numbers (SPNs) of meters that are outside the Adelaide region, but are supplied with water by WTPs within the Adelaide region. The SPNs were then used to extract water meter readings for the 2011–12 year for each meter from the CSIS database.
Water consumption was calculated by analysing the difference between consecutive meter readings and summed for 2011–12. To account for meter readings that occurred immediately before or after 2011–12, metered consumption was apportioned based on the following equation:
Vr = ( tr / tm ) × Vm
Vr = volume for metered period within 2011–12 (ML)
tm = length of period between meter readings (days)
tr = length of metered period within 2011–12 (days)
Vm = volume for metered period (ML).
Assumptions, limitations, caveats and approximations