19.20 Other urban water decreases
The volume reported (7,747 ML) represents decreases from the urban water system due to:
- water treatment plant (WTP) losses (6,596 ML)
- wastewater treatment plant (WWTP) losses (1,151 ML).
|Water treatment plant||Inflow (ML)||Outflow (ML)||Loss (ML)|
|Onkaparinga Summit Storage||4,875||5,083||(208)|
|Wastewater treatment plant||Inflow (ML)||Outflow (ML)||Process loss (ML)|
|Bolivar High Salinity||8,714||8,708||6|
Metered inflow and outflow data for the seven WTPs listed in the following table were obtained from SA Water's SCADA database and/or MetDaily file for most of these WTPs. Inflow data were not available for the Barossa and Hope Valley WTPs. Barossa and Hope Valley WTP inflow was calculated from the respective WTP outflow, allowing for a 5% loss through the treatment process. Outflow data were not available for the Anstey Hill WTP. Instead, it was calculated assuming a 5% treatment process loss. The total process loss is the difference between WTP inflow and outflow.
|Water treatment plant||Inflow – quantification approach||Outflow – quantification approach|
|Myponga||Metered inflow||Metered outflow|
|Anstey Hill||Metered inflow||Metered inflow × 0.95|
|Summit Storage||Metered inflow||Metered outflow|
|Happy Valley||Metered inflow||Metered outflow|
|Barossa||Metered outflow × 1.05||Metered outflow|
|Little Para||Metered inflow||Metered outflow|
|Hope Valley||Metered outflow × 1.05||Metered outflow|
The 2010–11 year inflow to and outflow from WWTPs within the Adelaide region were supplied by each WWTP. The data are measured by flow gauges that were manually read and recorded by plant operators. The WWTP loss was the difference between metered inflow and outflow.
Assumptions, Limitations, Caveats and Approximations
- Volume does not include community wastewater management systems (CWMS) because the data were unavailable.
- Volume includes some wastewater collected from outside the Adelaide region and delivered to the Bird-in-Hand WWTP. However, this volume is negligible.
- For the Christies Beach, Glenelg, Hahndorf and Heathfield WWTPs zero losses are assumed because only the outflows are measured, so inflow is assumed to be the same.
This line item corresponds to 20.7 Other lumped water distribution decreases reported in the 2010 Account.
In the 2011 Account the following changes were made that caused values of the 2009–10 year to be restated.
- potable water export to urban areas outside Adelaide region was reported elsewhere at line item 19.11 Transfer of water outside region
- water treatment plant and wastewater treatment plant losses were reported here.
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 7,777 ML.
|2010 Account line item name
||Description||Volume at 30 June 2010 reported in 2010 Account (ML)
||Value difference to volume reported due to reclassification (ML)
||Volume at 30 June 2010 reported in 2011 Account (ML)
|20.7 Other lumped water distribution decreases||Potable water export||3,627||(3,627)|
|WTP plant losses||7,051||7,051|
|WWTP plant losses||726||726|