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Canberra

                                                                                                   

30.3 Unaccounted-for difference—groundwater store

                             

Quantification approach   


The unaccounted-for difference is the difference between total groundwater outflows (including groundwater extractions) and total groundwater inflows measured during 2009–10, as shown in the following table.

  Account Volume (ML)
  Opening balance groundwater store (as at 01 July 2009)
add Total 15 Groundwater inflows
minus Total 16 Groundwater outflows 890
minus Closing balance groundwater store (as at 30 June 2010)
  Unaccounted-for difference –890

– = no balance available

Because the volume of water in the groundwater stores within the Canberra region could not be quantified accurately due to the lack of data, the volume disclosed in the unaccounted-for difference (–890 ML) represents the change in the groundwater store that has been able to be quantified throughout the reporting period.

This change is based on an estimate of usage using groundwater licence and bore information from the NSW Office of Water and ACT Department of Environment, Climate Change, Energy and Water (See Line item 16.4.1 and Line item 16.4.2).