Table 1 shows that there is a surplus of available water assets over water liabilities and future water commitments that are expected to be settled within 12 months of the reporting date.
|Total water assets as at 30 June 2011||240,607|
|Less water assets not available to be accessed, taken or delivered:|
|Lakes and wetlands 1||38,500|
|Less total water liabilities as at 30 June 2011:||0|
|Less future water commitments expected to be settled within 12 months of the reporting date:|
|Expected diversion of surface water allocations (urban water system)||40,944|
|Surplus / (deficit) of available water assets over water liabilities and future water commitments expected to be settled within 12 months of the reporting date||159,274|
Only an estimate of the diversion of surface water allocation has been included as a future commitment expected to be settled within 12 months. It is assumed that this will similar to the volume reported under line item 17.12 Surface water allocation diversion – Urban system in the 2011 Account.
Based on average historical data, future inflows to the storages used for urban water supply are likely to be between 60,000 ML and 411,000 ML. On an average year, inflow to the reservoirs is 206,000 ML. Of this inflow, only a limited amount is available to ACTEW for delivery for urban use. Water is also required to maintain environmental flows along the Queanbeyan, Upper Murrumbidgee and the Cotter Rivers. Evaporation from the connected surface water store has not been included in this table.
Contingent water assets and water liabilities
In 2009 the Australian Capital Territory (ACT) Government endorsed the implementation of the Tantangara Transfer Project. The project is intended to provide the ACT increased water security in drought and the flexibility of access to established water trading markets within New South Wales (NSW).
To date the project has seen the acquisition of 4,145 ML of high security water entitlements and 12,523 ML of general security entitlements from outside the ACT. A project implementation plan is currently underway and will address a number of issues surrounding the operation of the Tantangara transfer, these include:
- Institutional and regulatory framework
- Water division operational planning
- ActewAGL corporate/divisional management integration
- Water market and critical management predictive modelling
- Upper murrumbidgee hydrodynamic modelling
- Stream gauging and water quality monitoring
- Statutory evaluation, reporting and commitment monitoring
- Community engagement and stakeholder management
- Upper murrumbidgee catchment management improvement
- Water utility reference group
- External reviews and audits
- Risk management
- Project delivery and administration.
Operation of the Tantangara transfer is contingent on the completion of the Murrumbidgee to Googong Water Transfer project and appropriate arrangements between the ACT and NSW. The Googong transfer pipeline is expected to be operational in mid-2012 and the Tantangara Transfer project is expected to be established in 2012–13. Given that the required steps for the Tantangara transfer to become operational are outside the control of ACTEW this is considered a contingent water asset.