The Sydney region
Overview of the 2012–13 year
The Sydney region encompasses the Shoalhaven river catchment to the south, the Hawkesbury-Nepean catchment to the north, and the Illawarra and metropolitan rivers which flow through its major urban centre. As well as the metropolis of Sydney the region supports many populated centres such as Nowra, Goulburn, Lithgow and Moss Vale, as well as large areas of conservation and agriculture. Water administration, supply and management are carried out by several authorities such as the New South Wales Office of Water, the Sydney Water Corporation, the Sydney Catchment Authority, and several local councils.
The Sydney region water requirements are serviced by the extensive surface water storage network, which has been developed to meet the water needs of the most populous city in Australia. The streamflow captured from the region's major rivers is used mainly for urban water supply and agriculture. The Kurnell Desalination Plant and the Fish River Water Supply Scheme also provide water to the region, primarily for urban supply and power generation, although the Kurnell Desalination plant did not supply any water in the 2012–13 year. Groundwater represents less than 6% of all water rights in the region and is mainly used for domestic and stock purposes.
Though it was a dry start to the 2012–13 year, average annual rainfall was observed due to several substantial rainfall events later on in the year. This follows a year of above average rainfall in 2011–12. Over each year, the storages of the region were at full, or close to full, capacity. The total volume of water held in storage at the end of 2011–12 was 2,776,537 ML and 2,813,222 ML at the end of 2012–13, an increase of 36,685 ML. Closing net water assets in the Sydney region were 2,841,107 ML. In the 2012–13 year, the urban water system drew more water from the surface water network than in the 2011–12 year, due to the reduction in use of desalination water and a slight increase in the volume of urban water supplied.
The key water account information for the Sydney region during the 2012–13 year is presented in the following table. Information on the uncertainty associated with the volumes presented in the table is provided in the relevant sections of the account.For more information on the region's water assets refer to Water accounting statements.
Key water account information for the Sydney region during the 2012–13 year
2012–13 | 2011–12 | Long–term average | |
Rainfall: 904 mm | Rainfall: 1,184 mm | Rainfall: 898 mm | |
Evapotranspiration: 740 mm | Evapotranspiration: 858 mm | Evapotranspiration: 745 mm | |
For more detail on the Sydney climate refer to Climate overview. |
Shoalhaven River | Colo River | Comment | |
below average flows for most of the year, above average flows during February and June | below average for most of the year, above average flows during February and March | higher rainfalls in January, February and June contributed to higher flows during those periods | |
For more detail on streamflow in the Sydney region refer to Water overview. |
2012–13 | 2011–12 | ||
Total water assets (as at 30 June) | 2,783,245 | 2,236,318 | |
Total water liabilities (as at 30 June) | 0 | 0 | |
Change in net water assets | 57,862 | 546,927 | |
Closing net water assets | 2,841,107 | 2,783,245 | |
For more detail on water assets and water liabilities refer to Water Accounting statements. |
Notes: Water resources and systems
30 June 2013 | 30 June 2012 | ||||
Total capacity | Volume | % of capacity | Volume | % of capacity | |
2,862,622 ML | 2,813,222 ML | 98% | 2,776,537 ML | 97% | |
For more detail on surface water storage in the Sydney region refer to Surface water. |
Total water abstracted | |||
2012–13 | 2011–12 | Recent activity | |
Surface water: 612,290 ML | Surface water: 505,683 ML | water diverted by urban utilities from rivers and storages increased by 101,726 ML, no desalinated water supply in 2012–13 | |
Desalinated water: 0 ML | Desalinated water: 61,290 ML | ||
For more detail on water abstraction in the Sydney region refer to Surface water. |
Total water supplied | |||
2012–13 | 2011–12 | Recent activity | |
543,311 ML | 502,296* ML | while water diverted by urban utilities increased, water supplied to customers was similar to last year | |
For more detail on the urban water system in the Sydney region refer to Urban water system. |
*In 2011-12 the reported value of 489,557 ML was derived from urban water consumption data. This has been changed to the urban water supply value this year to 502,296 ML.