Adelaide
20.4 Delivery to irrigation scheme users
Supporting Information
The volume reported in the water accounting statement (14,789 ML) represents the volume of water that was delivered from the irrigation scheme to users in the Adelaide region in the 2010–11 year.
| Irrigation scheme | Volume (ML) |
| Barossa Infrastructure Limited (BIL) | 2,424 |
| Willunga Basin Water Company (WBWC) | 1,651 |
| Virginia Pipeline Scheme (VPS) | 10,714 |
| Total | 14,789 |
Quantification Approach
Data Source
Provided by
Method
Virginia Pipeline Scheme
The volume reported is from a meter at the Virginia Pipeline Scheme pump station.
Barossa Infrastructure Limited
The volume of water supplied to the customers was derived by subtracting the volume of leakage (line item 20.3) from the total volume of water delivered to BIL (sum of line items 12.6 and 12.18).
Calculation |
Volume (ML) |
12.6 Delivery of water to irrigation scheme under inter-region agreement |
2,301 |
12.18 Other irrigation water increases |
185 |
20.3 Leakage to groundwater |
(62) |
20.4 Application of water for irrigation |
2,424 |
Willunga Basin Water Company
The volume of water delivered via the Willunga Basin Water Company (WBWC) to customers was provided from WBWC. The volume is roughly equivalent to the inflows to the WBWC reported at line items 12.4 and 12.18.
Assumptions, Limitations, Caveats and Approximations
Virginia Pipeline Scheme
Customers' meters are not read in June or July as this does not correspond to the the irrigation water year. The volume reported was from the Virginia Pipeline Scheme pumping station and therefore the volume actually delivered to customers may be different due to leakage between the pumping station and customer meters.
Estimate that the actual volume of water measured at customers' meters is 5% less due to blocked meters and burst pipes.
Barossa Infrastructure Limited
- Customers' meters cannot be used directly as they were read to represent the water year (1 October – 31 September). Instead the water delivered to BIL from all sources, which was collected to represent the financial year, was reduced the volume of leakage. This assumes leakage within the water year represents leakage during the financial year.
- The area serviced by BIL extends beyond the boundary of the Adelaide region. It was assumed that the length of BIL infrastructure outside the Adelaide region is insignificant.
Uncertainty Information
Comparative year
This corresponds to line item 20.3.1 Application of irrigation water from water distribution system reported in the National Water Account 2010. In 2011 there were two important changes to the way in which this item was reported:
- In 2010 this line item was reported as part of the water distribution system store (urban water supply system), however in 2011 the Irrigation water supply system has been reclassified as a separate store.
- In 2010 only the irrigation scheme operated by BIL was reported on, however in 2011 two additional irrigation schemes were reported on.
Despite these changes, the restated volume for this item was unchanged (4,890 ML). Data on volumes of water delivered to irrigation scheme users from the Virginia Pipeline Scheme and the Willunga Basin Water Company was not available for the 2009–10 year.