20.15 Other irrigation scheme decreases

Supporting Information

This line item refers to transfers of water from the Harvey Water irrigation scheme to surface water storages within the Perth region.

Quantification Approach

Data Source

Water Corporation: Operational Data Storage System.

Provided by

Water Corporation.


The total volume of water transferred from the irrigation scheme is based on measured inflow data at the major surface water storages. During the 2010–11 year, no such transfers of water occurred.

Assumptions, Limitations, Caveats and Approximations


Uncertainty Information

Expected error for water meters is +/– 5%.

The Department of Water requires that all water meters, when tested in situ conditions, must be within 5% accuracy across the full flow rate range (Guidelines for water meter installation 2009).

Comparative year

The following table presents substantive changes in the line item reported in this 2011 Account with the corresponding line item in the 2010 Account.


Comparative year information for line item 20.15

2011 Account line item

2010 Account line item

2011 Account volume for the 2009–10 year (ML)

2010 Account volume for the 2009–10 year (ML)

Change from the 2010 Account to the 2011 Account

20.15 Other irrigation scheme decreases

20.7 Other lumped water distribution system decrease



Change in line item name and number