Canberra: Outlook

Future prospects

This section looks forward over the next reporting period and considers what water inflows, commitments and other releases (e.g. dam operation releases and spills) might affect the region's water resources during the 2016–17 year. Figure S16 shows that there is a surplus of available water assets and future water rights over water liabilities and future water commitments that are expected to be settled within 12 months of the reporting date.

Figure S16 Water outlook for the Canberra region for 2016–17

Expected inflows

At the time of publication, rainfall over the Canberra region during the first nine months of the 2016–17 year (July–March) was generally average to above average (Figure S17).

 Figure S17 Rainfall deciles for the Canberra region from July 2016–March 2017

The Bureau's climate outlook (released on 30 March 2017) indicates a high probability of below-average rainfall over most of southern Australia, including the Canberra region, for the next three months (April–June 2017). This outlook is influenced by warming of tropical Pacific sea surface temperatures and a cooler than average eastern Indian Ocean. Therefore, given the current below-average soil moisture conditions in March 2017 (see the Bureau's Australian Landscape Water Balance product), annual streamflows and storage inflows are expected to be slightly below average during the 2016–17 year.

The expected inflows for the 2016–17 year are based on the 2013–14 year, a period when similar average rainfall conditions were experienced. Based on these assumptions, the combined expected precipitation (approximately 14,000 ML) and river inflows into the storages (approximately 175,000 ML) could well exceed the expected evaporation from the storages (approximately 19,000 ML) during the year.

Future commitments

The expected diversions and extractions are based on water use data for the 2015–16 year; however, other water releases such as dam spills are expected to decrease over the next reporting period. 

Contingent water assets

Tantangara Transfer Project

In 2009 the ACT Government endorsed the implementation of the Tantangara Transfer Project. The project is intended to provide the ACT with increased water security in droughts and the flexibility of access to established water trading markets within NSW.

The Tantangara Transfer Project involves transferring water from the regulated Murrumbidgee River (below Burrinjuck and Blowering dams) to the ACT via the Snowy Mountains Scheme. The following steps are required:

• purchase NSW water entitlements from Murrumbidgee regulated river licence holders downstream of the ACT
• negotiate a long-term, secure, and flexible commercial agreement with Snowy Hydro Limited for the release of water from Tantangara Reservoir
• establish an intergovernmental agreement between the NSW and ACT governments to allow for the transfer of water from NSW to the ACT via the Tantangara Reservoir and for the return of transfers if unused
• deliver water to the ACT via the unregulated Murrumbidgee River above the ACT
• extract water from the Murrumbidgee River via the Murrumbidgee to Googong water transfer pipeline at Angle Crossing
• enable storage of the water in Googong Reservoir until used
• enable trade of purchased water back to NSW if not used.

The Tantangara Transfer Project agreements were completed during the 2013–14 year to enable the delivery of water if required. Some details regarding the obligations of ACT and NSW governments are still to be finalised but these are not essential for Icon Water to access the water. Present high storages mean that it will be some time before a Tantangara transfer is required.

The Tantangara Transfer Project is continuing. Icon Water holds 9,549 ML of high-security NSW water entitlements. These water entitlements are from the NSW regulated Murrumbidgee River and are to be utilised under the Tantangara Transfer Project. This option is to be available for use only during extreme droughts.

The Tantangara transfer is considered a contingent water asset and is subject to appropriate arrangements between the ACT and NSW governments.

Murrumbidgee to Googong water transfer

Water transfer through the Murrumbidgee to Googong pipeline has not yet been effected except for maintenance purposes. It enables the transfer of up to 100 ML of water per day but the amount of water that can be transferred each day will depend on the availability of water in the Murrumbidgee River, maintenance of the Murrumbidgee River environmental flows, and the available storage capacity in Googong Reservoir.