Murray-Darling Basin
9.9 Discharge from urban water system

Supporting Information

The volumetric value for the line item for the 2010–11 year was 34,897 ML. The volume represents treated urban wastewater discharge to surface water within Australian Capital Territory and Murrumbidgee New South Wales surface water resource plan areas. Information from other urban water systems was not available. The line item value splits as follows:

  • Lower Molonglo Water Quality Control Centre: 32,243 ML

  • Queanbeyan Wastewater Treatment Plant: 2,654 ML

When there is storage capacity, water diverted from the rivers is treated at Mount Stromlo Water Treatment Plant and then transferred to Googong Reservoir via the water reticulation network. Transferred volume, 4,364 ML for 2010–11 is not included in the line item value because this volume has already been accounted in line item 9.4 Runoff to surface water.

Quantification Approach

Data Source

ActewAGL Water Data Warehouse and Queanbeyan City Council database.

Provided by

ActewAGL and Queanbeyan City Council.


Treated wastewater discharged to the surface water store was measured at wastewater treatment plant outflow flow meters.

Assumptions, Limitations, Caveats and Approximations


Uncertainty Information

Volumes were derived from measured data. Estimated uncertainty is +/– 5%.

Comparative year

The value reported as comparative year corresponds to the line item 13.7.1 Discharge of urban wastewater to surface water that was reported in the 2010 Account.