11.12 Entitled diversion of allocated surface water to urban water system
a. Urban water supply system overview
The urban water supply system is one of three sub-components of Canberra's urban water system. The three sub-components are the:
- Urban water supply system
- Wastewater system
- Recycled water system.
Surface water (11.12) is the main source of water for Canberra's urban water supply system.
Urban water consumption (part of 19.4) was 38,852 ML during the 2011–12 year, representing 93% of all urban water supply system outflows. The remaining urban water was lost through operational losses.
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 Canberra's urban water supply system. Line item numbers are provided in brackets.
b. Supporting information
The volume recognised in the surface water statements (41,790 ML) represents the total surface water diverted for urban water supply in the Canberra region during the 2011–12 year.
This line item refers to the amount of water that was diverted under ACTEW's urban water access entitlement. A breakdown of the amount of water diverted from each reservoir is provided in the following table.
|Water Storage||Volume (ML)|
|Murrumbidgee River1|| 0
|Return to Googong 2||0|
1 Diversions from the Murrumbidgee River have been included in this line item in National Water Account 2012 as diversions are based upon the same licence as extractions from the water storages.
2 This value represents the volume of water transferred to the Googong Reservoir from the Cotter Reservoir or Murrumbidgee River to take advantage of the storage capacity in the Googong Reservoir.
The total volume taken from surface water for urban water supply in the 2011–12 reporting year was calculated as the volume diverted from the Bendora, Corin, Cotter and Googong reservoirs together with the volume diverted from the Murrumbidgee River. These are metered volumes obtained from the ACTEW Water production records.
Assumptions, limitations, caveats and approximations
The volume of water reported in this line item captures the total volume diverted from the water storages and the Murrumbidgee River.
Derived from measured data. Estimated uncertainty is +/–5%.
This line item corresponds to line item 11.12 'Allocation diversion of surface water to urban water system' reported in the 2011 Account.