National Water Account 2017

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Key findings

Climate and water

Water Accounting Statements

Supporting information

Region description

Reference information

Canberra: Statement details

Water assets

Storages

• Water asset volumes in the region at 30 June 2017 were 279,006 ML, more than 85% of which is water held in storages.

Figure S1 Total storage volume in the region at 30 June 2017 compared with the previous 7 years

• Storage volumes increased slightly from 83% full at 30 June 2016 to 84% full (238,900 ML) at 30 June 2017. This is the region's fourth consecutive increase in end of year storage volume.
• Above-average rainfall during winter and spring 2016 contributed to storage volumes reaching 100% full in mid-October 2016. Storage volumes then steadily decreased for the remainder of the year.
• In 2013 the Cotter Reservoir was enlarged, increasing the region's total storage capacity to better deal with water demand during periods of drought (see 2013 Account).

Figure S2 Percentage-full volume on 30 June 2017 for each storage

• All storages in the region were greater than 60% full at 30 June 2017. Last year, Bendora Reservoir was less than 60% full and Corin Reservoir was less than 40% full (see 2016 Account).
• Googong Reservoir is the region’s secondary source of water and is only used to meet demand during dry periods. The reservoir has remained full, or near full, since the end of the Millennium Drought in 2010, as only limited water has been sourced from the reservoir during this period.
• More detailed information on the individual storages within the region is available on the Bureau of Meteorology's Water Storage website.

Lakes and wetlands

• 14% of the total water asset volume was water held in lakes and wetlands.

Figure S3 Total lake volume at 30 June 2017 compared with the previous 7 years

• Lake volumes decreased marginally from 101% full at 30 June 2016 to 100% full (39,174 ML) at 30 June 2017.
• These lakes are primarily used for recreation, conservation, and aesthetic purposes and are not formally associated with the urban water supply system.

Figure S4 Percentage-full volume on 30 June 2017 for each major lake

• Lake Ginninderra, Lake Burley Griffin and Lake Tuggeranong were all at capacity for the third consecutive year.

Water liabilities

• Water liabilities in the Canberra region refer to the volume of allocation remaining on licence entitlements at the end of the 2016–17 year.

• The water supply licences for the region have a water management year that ends on 30 June. The portion of water allocation that has not been abstracted at the end of the water year is either forfeited or is carried over into the next water year.
• As the carryover cannot be quantified, the unused portion of the allocation is assumed to be forfeited and the allocation remaining at the end of the year was 0 ML.
• A more detailed description of water allocations and associated water rights in the Canberra region is given in the Water rights note.

Water asset increases

• Total water asset increases for the year was 1,020,192 ML.
• The key items contributing to water asset increases were runoff and inflow, which together made up more than 94% of the total water asset increases. Runoff was 24% higher than the previous year, which can be attributed to heavy rainfall during September that caused very high flows across the region (see Climate and water).
• Urban water system increases primarily represent wastewater collected, which changes little from year to year.

Water asset decreases

• Total water asset decreases for the year was 974,414 ML.
• The key item contributing to the water asset decrease for the region was outflow, which made up more than 86% of the total water asset decreases. Outflow was higher than the previous year, which can be attributed to heavy rainfall during September that caused very high flows across the region (see Climate and water).
• Urban water system decreases primarily represent supply system delivery: urban users, which generally change little from year to year.

Water flows

• Total water inflows to the region was 1,020,192 ML, equal to the volume of Water asset increases.
• Total water outflows from the region was 974,414 ML, equal to the volume of Water asset decreases.
• A detailed description on all the water flows associated with the surface water store, groundwater store, and urban water system is provided in the Water stores note.

Unaccounted-for difference

• The unaccounted-for difference is the volume necessary to reconcile the opening water storage and closing water storage with the total water inflows and total water outflows reported in the water accounting statements.

• The unaccounted–for difference volume is primarily attributed to the fact that river losses cannot be quantified in the account, as well as uncertainties associated with the runoff estimate (see Methods).