Perth: Statement of Changes in Water Assets and Water Liabilities
Water availability in the Perth region increased by 39,883 ML during the 2016–17 year. This follows a decrease in water availability in the previous year. The change in water available in the region at the end of the year is represented by the change in net water assets.
The Statement of Changes in Water Assets and Water Liabilities is provided in the table below. The statement presents the changes in water assets and water liabilities that occurred during the year, including accrual transactions (e.g. allocations and forfeitures) and actual water flows, both natural and engineered.
2017 ML | 2016 ML | |
---|---|---|
Water asset increases | ||
Surface water increases | 1,341,861 | 438,728 |
Precipitation | 37,453 | 16,824 |
Runoff | 840,406 | 352,148 |
Delivery: inter-region | 0 | 0 |
Inter-region inflow | 444,083 | 69,756 |
Flood return | 19,919 | – |
Groundwater increases | 1,612,825 | 1,212,581 |
Inter-region inflow | 45,724 | 47,475 |
Inter-region coastal inflow | 0 | 0 |
Recharge: landscape | 1,567,101 | 1,165,106 |
Urban water system increases | 292,143 | 279,456 |
Wastewater collected | 140,439 | 138,858 |
Supply system delivery: inter-region | 1,832 | 1,953 |
Delivery: desalinated water | 149,872 | 138,645 |
Total water asset increases | 3,246,829 | 1,930,765 |
Water liability decreases | ||
Surface water liability decreases | 21 | 50 |
Adjustment and forfeiture: individual users | 21 | 50 |
Groundwater liability decreases | 12,541 | 8,755 |
Adjustment and forfeiture: individual users | 12,541 | 8,755 |
Total water liability decreases | 12,562 | 8,805 |
Water asset decreases | ||
Surface water decreases | 1,560,606 | 225,475 |
Evaporation | 48,591 | 28,912 |
Outflow | 1,221,652 | 196,413 |
Leakage: landscape | 150 | 150 |
River losses | 238,759 | – |
Overbank flow | 51,454 | – |
Groundwater decreases | 751,022 | 735,954 |
Inter-region outflow | 19,350 | 21,863 |
Inter-region coastal outflow | 261,169 | 300,629 |
Discharge: landscape | 389,247 | 332,617 |
Non-allocated extraction: individual users | 81,256 | 80,845 |
Urban water system decreases | 387,682 | 411,311 |
Supply system delivery: urban users | 224,799 | 236,200 |
Recycled water delivery: urban users | 8,622 | 9,095 |
Discharge: sea | 119,190 | 123,163 |
Discharge: landscape | 5,734 | 6,145 |
Supply system transfer: inter-region | 20,883 | 27,923 |
Other supply system decreases | 8,454 | 8,785 |
Irrigation scheme decreases | 59,377 | 70,657 |
Delivery | 43,456 | 53,456 |
Leakage: landscape | 15,921 | 17,201 |
Total water asset decreases | 2,758,687 | 1,443,397 |
Water liability increases | ||
Surface water liability increases | 38,873 | 38,842 |
Allocation: individual users | 38,873 | 38,842 |
Groundwater liability increases | 299,034 | 306,671 |
Allocation: individual users | 299,034 | 306,671 |
Total water liability increases | 337,907 | 345,513 |
Unaccounted-for difference | (122,914) | (221,217) |
Change in net water assets | 39,883 | (70,557) |