Melbourne

The volumes recognised in the water accounting statements (735 ML) represent the volume of water held in the recycled water supply system managed by South East Water.

This item does not include the urban recycled water storages operated by Melbourne Water. The volume in storage at both the Western and Eastern treatment plants are disclosed at Line item 5.2 Urban wastewater system.

Data source

Supervisory control and data acquisition (SCADA).

Data provider

South East Water.

Method

Level readings are taken from a level sensor. The related volume is read from a capacity curve.

Uncertainty

Uncertainty exists in the level sensor equipment, which is calibrated on a routine basis. Volumes are derived from measured level data. Estimated uncertainty is +/–5%.

Approximations, assumptions, caveats/limitations

• Capacity curves represent specifically surveyed parts of the water recycling system, and may not reflect the storage-volume relationship across the entire system.
• Recycling systems are subject to sedimentation and other physical changes over time, which in turn affects the accuracy of the capacity curve.