This line item refers to the total water used for the irrigation of household lawns and gardens within the Perth region.
Water Corporation: Operational Data Storage System.
Water Corporation.
The amount of potable water used for outdoor use is calculated as a percentage of the total water supply, based on the Perth Residential Water Use Study 2008-2009 (Water Corporation, 2009). According to this study, approximately 39% of the total public water supply is used for outdoor use.
The total water supply (and outdoor water use) is calculated according to the table below.
|
|
|
Volume (ML) |
|---|---|---|
|
|
14.7.2.4 Surface water diversion |
141,285 |
|
Plus |
16.5.3.4 Groundwater diversion |
120,828 |
|
Plus |
19.5.1 Desalinated water supply |
47,693 |
|
|
Total water abstracted |
309,806 |
|
Less |
13.8 Internal transfers |
45,233 |
|
Less |
Riparian releases |
4,818 |
|
Less |
Leakage to groundwater |
11,909 |
|
Less |
Operation losses |
893 |
|
|
Total water supplied |
246,953 |
|
|
Total outdoor use |
96,312 |
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 (Department of Water 2009).
Actual outdoor water use is not measured. The value reported here is an estimate only.