Perth: Statement of Water Assets and Water Liabilities
For the water account period 1 July 2024 to 30 June 2025
- In the Perth region, water availability increased by 6% during 2024–25, primarily due to increases in surface water and groundwater assets.
- Water availability is represented by the net water assets, which are the volume of water assets minus the water liabilities.
The Statement of Water Assets and Water Liabilities provides a detailed breakdown of the volume of water assets and water liabilities in the Perth region over the past six water accounting periods ending 30 June, as well as changes in net water assets between the start (1 July) and end (30 June) of each reporting period.
To view the Statement of Water Assets and Water Liabilities, scroll down to the table below.
Select comparative year
| 2025 (ML) | 2024 (ML) | 2023 (ML) | 2022 (ML) | 2021 (ML) | 2020 (ML) | ||
|---|---|---|---|---|---|---|---|
| Water assets | |||||||
| Surface water | 343,584 | 334,109 | 439,851 | 471,626 | 365,461 | 360,126 | |
| Accessible storage | 320,128 | 310,234 | 414,904 | 446,663 | 339,106 | 332,479 | |
| Dead storage | 23,098 | 23,098 | 23,098 | 23,098 | 23,098 | 23,098 | |
| Rivers | 358 | 777 | 1,849 | 1,865 | 3,257 | 4,549 | |
| Groundwater | - | - | - | - | - | - | |
| Aquifers | - | - | - | - | - | - | |
| Urban water supply | 0 | 0 | 0 | 0 | 0 | 0 | |
| Urban water claims on surface water* | 0 | 0 | 0 | 0 | 0 | 0 | |
| Urban water claims on groundwater* | 0 | 0 | 0 | 0 | 0 | 0 | |
| Irrigation scheme | 23,271 | 25,007 | 28,373 | 29,864 | 31,798 | 31,831 | |
| Irrigation scheme claims on surface water* | 23,271 | 25,007 | 28,373 | 29,864 | 31,798 | 31,831 | |
| Total water assets | 366,855 | 359,116 | 468,224 | 501,490 | 397,259 | 391,957 | |
| Water liabilities | |||||||
| Surface water liability | 33,310 | 35,016 | 38,382 | 39,873 | 40,320 | 40,353 | |
| Surface water allocation remaining: individual users | 10,039 | 10,009 | 10,009 | 10,009 | 8,522 | 8,522 | |
| Surface water liability to urban water supply* | 0 | 0 | 0 | 0 | 0 | 0 | |
| Surface water allocation remaining: irrigation scheme* | 23,271 | 25,007 | 28,373 | 29,864 | 31,798 | 31,831 | |
| Groundwater liability | 92,513 | 97,313 | 104,182 | 102,352 | 102,376 | 102,377 | |
| Groundwater allocation remaining: individual users | 92,513 | 97,313 | 104,182 | 102,352 | 102,376 | 102,377 | |
| Groundwater liability to urban water supply* | 0 | 0 | 0 | 0 | 0 | 0 | |
| Total water liabilities | 125,823 | 132,329 | 142,564 | 142,225 | 142,696 | 142,730 | |
| Net water assets | |||||||
| Net surface water assets | 310,274 | 299,093 | 401,469 | 431,753 | 325,141 | 319,773 | |
| Opening net surface water assets | 299,093 | 401,469 | 431,753 | 325,141 | 319,773 | 367,821 | |
| Change in net surface water assets | 11,181 | (102,376) | (30,284) | 106,612 | 5,368 | (48,048) | |
| Closing net surface water assets | 310,274 | 299,093 | 401,469 | 431,753 | 325,141 | 319,773 | |
| Net groundwater assets | (92,513) | (97,313) | (104,182) | (102,352) | (102,376) | (102,377) | |
| Opening net groundwater assets | (97,313) | (104,182) | (102,352) | (102,376) | (102,377) | (102,377) | |
| Change in net groundwater assets | 4,800 | 6,869 | (1,830) | 24 | 1 | 0 | |
| Closing net groundwater assets | (92,513) | (97,313) | (104,182) | (102,352) | (102,376) | (102,377) | |
| Net urban water assets | 0 | 0 | 0 | 0 | 0 | 0 | |
| Opening net urban water assets | 0 | 0 | 0 | 0 | 0 | 0 | |
| Change in net urban water assets | 0 | 0 | 0 | 0 | 0 | 0 | |
| Closing net urban water assets | 0 | 0 | 0 | 0 | 0 | 0 | |
| Net irrigation water assets | 23,271 | 25,007 | 28,373 | 29,864 | 31,798 | 31,831 | |
| Opening net irrigation water assets | 25,007 | 28,373 | 29,864 | 31,798 | 31,831 | 40,634 | |
| Change in net irrigation water assets | (1,736) | (3,366) | (1,491) | (1,934) | (33) | (8,803) | |
| Closing net irrigation water assets | 23,271 | 25,007 | 28,373 | 29,864 | 31,798 | 31,831 | |
| Total closing net water assets | 241,032 | 226,787 | 325,660 | 359,265 | 254,563 | 249,227 | |
| Total change in net water assets | 14,245 | (98,873) | (33,605) | 104,702 | 5,336 | (56,851) | |
*between-store claims / liabilities
Note: quantification approaches used to derive each item volume are provided in the Methods