Perth: Statement of Water Flows
The volume of water in the region's storages at 30 June 2017 was 297,520 ML, an increase of 35,004 ML or 13% from the start of the 2016–17 year. This reflects the increase in water volume of most the region's surface water storages. This is the region's first annual increase in three years.
The Statement of Water Flows is provided below and presents the actual water flows associated with the region's water stores during the year, including flows corresponding to the accrual transactions shown in the Statement of Changes in Water Assets and Water Liabilities.
| 2017 ML | 2016 ML | |
|---|---|---|
| Water inflows | ||
| Surface water inflows | 1,341,861 | 438,728 |
| Precipitation | 37,453 | 16,824 |
| Runoff | 840,406 | 352,148 |
| Inter-region inflow | 444,083 | 69,756 |
| Flood return | 19,919 | – |
| Groundwater inflows | 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 inflows | 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 inflows | 3,246,829 | 1,930,765 |
| Water outflows | ||
| Surface water outflows | 1,599,456 | 264,184 |
| Evaporation | 48,591 | 28,912 |
| Outflow | 1,221,652 | 196,413 |
| Leakage: landscape | 150 | 150 |
| River losses | 238,759 | – |
| Overbank flow | 51,454 | – |
| Allocated diversion: individual users | 38,850 | 38,709 |
| Groundwater outflows | 1,042,396 | 1,035,708 |
| 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 |
| Allocated extraction: individual users | 291,374 | 299,754 |
| Urban water system outflows | 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 outflows | 8,454 | 8,785 |
| Irrigation scheme outflows | 59,377 | 70,657 |
| Delivery | 43,456 | 53,456 |
| Leakage: landscape | 15,921 | 17,201 |
| Total water outflows | 3,088,911 | 1,781,860 |
| Unaccounted-for difference | (122,914) | (221,217) |
| Opening water storage | 262,516 | 334,828 |
| Change in water storage | 35,004 | (72,312) |
| Closing water storage | 297,520 | 262,516 |