Table 1 shows that there is a surplus of 80,915 ML of available water 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||
|Less water assets not available to be accessed, taken or delivered within 12 months of the reoprting date|
|Less total water liabilities as at 30 June3||
|Less future commitments expected to be settled within 12 months of the reporting date||
|Expected non-licensed surface water diversions4||
|Expected allocation diversion of surface water5||
|Expected non-licensed groundwater extractions6||
|Expected allocation extraction of groundwater7||
|Expected urban water use8||
|Expected irrigation schemes water use9||
|Surplus / (deficit) of available water assets over water liabilities and future commitments expected to be settled within 12 months of the reporting date||
|add future inflows and future water rights expected to be realised within 12 months of the reporting date||
|Transfer into urban water system of River Murray water10||
|Transfer into irrigation schemes of River Murray water11||
|Surplus / (deficit) of available water assets, expected future inflows and future water rights over water liabilities and future water commitments within 12 months of the reporting date||
1 Dead storage for surface water 1.1 Storages and 1.2 Unregulated river
4 Average of the 2010–11 and 2011–12 years surface water diversions reported at 17.6 Surface water diversions – other statutory rights
5 Average of the 2010–11 and 2011–12 years surface water diversions reported at 17.11 Entitled diversion of allocated surface
6 Average of the 2010–11 and 2011–12 years groundwater extractions reported at 18.7 Groundwater extractions – other statutory rights
7 Average of the 2010–11 and 2011–12 years groundwater extractions reported at 18.11 Entitled extractions of allocated groundwater
8 Average of the 2010–11 and 2011–12 years urban water use reported at 19.4 Delivery to urban water system users
9 Average of the 2010–11 and 2011–12 years irrigation schemes water use reported at 20.4 Delivery to irrigation scheme users
10 Average of the 2010–11 and 2011–12 years River Murray water transferred into the region's urban water system reported at 11.9 Delivery of water to urban water system under inter-region agreement
11 Average of the 2010–11 and 2011–12 years River Murray water transferred into the region's irrigation schemes at 12.6 Delivery of water to irrigation scheme under inter-region agreement
12 The capacity of the Adelaide desalination plant during the 2012–13 year became 100,000 ML/year. The volume of expected inflows of desalinated water to the urban water system was quantified as the measured value for the 2012–2013 year. For further information see the SA Water website.
It should be noted that Table 1, with the exception of desalinated water, does not include expected water inflows for 2012–13 due to lack of appropriate data and a suitable quantification approach.
The volumes reported for future water rights and future water commitments are indicative only. The volumes presented in Table 1 were estimated from the average diversions and extractions in the previous two years. The actual volume of water delivered under these future water rights and future water commitments will depend on climatic conditions and demand.
Above-average rainfall was experienced in the Adelaide region in the 2010–11 year while the 2011–12 year was close to average. Over these two years climatic conditions increased water availability and reduced the demand on water resources. These conditions suggest that averaged surface water diversions and groundwater extractions over these previous two years are likely to underestimate expected diversions and extractions in an average rainfall year.
Preliminary climate data available when the 2012 Account was compiled suggest that the 2012–13 year will be drier than the previous two years. If these conditions persist, the future prospects suggested in Table 1 may overestimate the surplus of available water assets, expected future inflows, and future water rights over water liabilities and future commitments expected to be settled within 12 months of the reporting date. On the other hand, future direct rainfall on the watercourses and storages, runoff and groundwater recharge within the Adelaide region that could not be estimated for the 2012–13 year will contribute to increase that surplus. Transfers of water from the River Murray and the Adelaide desalination plant may also be increased in case of need. Therefore it is likely that future demands on the Adelaide region's water resources will be met.
Contingent water assets and water liabilities
Contingent water assets
The non-extractable portion of groundwater in the Adelaide region:
The Adelaide and Mount Lofty Ranges Natural Resources Management (NRM) Board develops water allocation plans for the prescribed water resources within the Adelaide region. A water allocation plan describes the capacity of the groundwater resources to meet demand. The non-extractable portion of the groundwater asset is a contingent water asset because it is possible that a change in circumstances, such as legislative or regulatory changes that alter the extraction limits, would result in further portions of the groundwater becoming available for extraction. There is no estimate available of the total volume stored in the aquifers of the region.
Contingent water liabilities
Groundwater and surface water allocations in the Western Mount Lofty Ranges Adelaide region
The Adelaide and Mount Lofty Ranges NRM Board have drafted a water allocation plan for the water resources (surface water and groundwater) within the Western Mount Lofty Ranges. The water allocation plan provides for the allocation and use of water within the region. The draft plan specifies extraction limits on the surface water and groundwater resources: future water allocations might reach those levels if the resources are fully allocated. The draft plan was released for public consultation in late 2010 but had not been adopted during the 2011–12 year. The approval and adoption of the water allocation plan for the Western Mount Lofty Ranges by the South Australian Government is outside the control of the management of the Adelaide region. Therefore, the extraction limits detailed in the draft plan are considered contingent water liabilities:
- 70,000 ML of groundwater contingent water liability, corresponding to the underground water extraction limit; and
- 87,576 ML of surface water contingent water liability, corresponding to the surface water (main watercourse) extraction limit.
Water for urban use
SA Water supplies urban water to residential customers throughout the Adelaide region. SA Water maintains water within its distribution pipes for the delivery of water to the city, but the actual delivery of water is determined by the customers when they turn on the tap. Therefore, the delivery of urban water to customers within the Adelaide region is considered a contingent water liability. During the 2011–2012 year 133,354 ML of urban water was supplied to residential customers within the Adelaide reporting region. Notwithstanding any major changes, it is estimated that a similar volume of water will be required to be delivered in the next reporting period.