11.18 Increase of urban claim on surface water
This line item consists of the volume of water allocated to ACTEW for use based on their licence to take water from the Cotter, Queanbeyan and Murrumbidgee rivers for the purpose of urban water supply. As the 2011 Account defines water storages as part of the surface water, ActewAGL (as the urban water system operator) have the ability to order water from the surface water reservoirs operated by ActewAGL. This ability to order water is, for the purpose of the 2011 Account, seen as an urban claim on surface water or a surface water liability.
Although an allocation announcement does not occur for ACTEW's licence each year, for the purpose of the 2011 Account, it has been assumed that an allocation announcement occurs. This allocation announcement has been assumed as 100% of the licensed volume.
Diversions on this licence are from various water storages and from the Murrumbidgee River. Despite the Murrumbidgee River diversions being physically unregulated, the right to divert the water has been included in this line item, and the diversions included in line item 11.12 Allocation diversion of surface water to urban system because the licence could not be separated.
Urban water access entitlements are available for inspection on a public register at the Australian Capital Territory (ACT) Government Environment and Sustainable Development Directorate, Macarthur House, 12 Wattle Street, Lyneham ACT 2602.
Water access entitlement volumes for 2010–11 were obtained from the ACT Water Resource Information Database.
The total annual announced allocation for 2010–11 assumed, for the purpose of the 2011 Account, to be 100% of the ACTEW urban water licence.
Assumptions, Limitations, Caveats and Approximations
There is no distinction between regulated and unregulated flows in ACTEW's urban water access entitlement. Water to service this licence is obtained from both regulated and unregulated sources, and therefore has been included in this line item. An overestimation in the true right to water within water storages has been overestimated.
The uncertainty estimate was not quantified.