Canberra
17.7 Entitled diversion of non–allocated surface water to users

Supporting information

The volume presented in the water accounting statements (1,415 ML) represents the volume of water diverted in the Canberra region for irrigation, stock and domestic, commercial and industrial and other surface water entitlements without prior allocation announcement.

This following presents the breakdown of non–allocated surface water diversions in the Canberra region.


Entitled non–allocated surface water diversions in the Canberra region during the 2011–12 year
Data Provider Holder type Volume (ML) 
ACT Government, Environmental and Sustainable Development Directorate (ESDD) Unavailable  740
New South Wales Office of Water Irrigation, farming  270
Industrial (sand and gravel) 57
Domestic, stock 10
Recreation 88
Within urban area (Palerang Council)  250
 Total
             1,415

Quantification approach

Data source

ESDD: Water Resources Unit, Water Resource Information Database; NSW Office of Water: Navigator Water Tools.

Provided by

ESDD, NSW Office of Water.

Method

Australian Capital Territory

This line item includes diversions of unregulated flows under multi-use licences for non–potable water within the Australian Capital Territory (ACT). It includes urban use for licensed abstraction within the urban area, and other use for licensed abstraction outside of the urban area.

Individual licensees submit monthly meter readings to the ACT Environment Protection Authority (EPA) on an annual basis. Where a licensee has not provided meter data, the EPA estimates usage based on historical usage data.

New South Wales

In the New South Wales (NSW) portion of the subaccount, use has been estimated to be 50% of the NSW Office of Water surface water licence volume for all entitlements within this line item, except for the urban entitlement for Palerang Council. Use for Palerang Council has been estimated as 100% of the entitlement.

The Navigator Water Tools ArcGIS add–on was used to query the NSW Office of Water database spatially and extract usage for the area inside the entity.

Assumptions, limitations, caveats and approximations

  • In NSW, the accuracy of Navigator Water Tools data is limited by the quantity and accuracy of the geographical coordinates defined in the licensing administration system.
  • Unregulated water use in NSW was assumed to be 50% of the total NSW Office of Water licence volume for all categories of entitlements, except for entitlements within the urban area (Palerang Council). Calculation of this estimate was carried out by the Bureau.

Uncertainty information

Australian Capital Territory

More than 60% of meters are inspected each year to validate the readings supplied by licensees. Estimated uncertainty for meter accuracy is +/–5 %. Uncertainty can not be quantified for estimated usage where meters were not read.

New South Wales

Derived from geographic information system data. Estimated uncertainty is +/– 30% to +/– 50% based on established practice and professional judgement by NSW Office of Water.