Perth weekly water update 1 October 2021
| Target | Actual | |
|---|---|---|
| October water use to date |
0.7 billion litres |
0.7 billion litres |
| Dam storage levels | N/A | 61.9% |
| Monthly streamflow into dams | N/A | 15.5 billion litres (September total) |
| October rainfall to date | 51.5 mm (October average rainfall 1876-2016) | 8.4 mm |
| Note: 1 billion litres = approximately 400 Olympic swimming pools. Please note the figures in this table are rounded (except for rainfall) to the nearest whole number. | ||
Water use
Average water use over the past week was 689 million litres per day – below the demand forecast of 703 million litres per day.
Daily water use for the last 5 days
| Date | Actual water use (million litres) | Forecast water use (million litres) |
|---|---|---|
| 01/10/2021 | 659 | 714 |
| 30/09/2021 | 694 | 714 |
| 29/09/2021 | 715 | 714 |
| 28/08/2021 | 704 | 714 |
| 27/08/2021 | 648 | 687 |
| Note, water use is calculated up to 8am each day for the previous 24 hour period. | ||
Since 1 July 2021 to date, we have used 58.83 billion litres of water – which is 2.05 billion litres above the forecast target for this period.
Dam levels (total for 15 dams)
The dam storage levels are slightly up on last week and are sitting at a combined 61.9 per cent* of full capacity.
*Please note some dams are filled from different sources - dam levels include the transfer of groundwater and desalinated seawater from treatment plants as well as streamflow (that comes from rainfall). As we use many different sources of water, dams are no longer an accurate indicator of the health of Perth's overall water supply situation.
Streamflow (total for 15 dams)
From 1 May 2021, the dams have received 115.4 billion litres of streamflow. The post-1975 average for the May to April period (called the streamflow year) is 178.4 billion litres.
Sprinkler roster compliance
Since 1 January 2021, we have taken a total of 4,542 actions (warnings + fines) compared with 4,460 actions for the same period in 2020.
Annual rainfall
Perth has received 725.3 mm of rainfall since 1 January 2021. The average (1876-2016) rainfall for the same period to the end of October is 809 mm.
General water news
130 years ago today, Perth's first water supply scheme was officially opened.
On 1 October 1891, Victoria Dam, located in the Darling Range, started supplying water to Mount Eliza Reservoir in Kings Park, replacing wells and other natural sources to accommodate for the growing population.
At the time, the scheme supported Perth’s entire population of around 11,500 people, with a maximum capacity of three million litres.
Mount Eliza reservoir has received multiple upgrades since then to accommodate Perth’s growing population, including the construction of three new storage ponds (water reservoirs) and two water distribution mains.
Today, the reservoir holds more than 45 million litres of water which is supplied to the Perth CBD and western suburbs.
Perth’s first public water supply scheme is significant as it improved public health and allowed Perth to grow in response to the State’s gold rush. It was also the predecessor for the equally historic goldfields pipeline and water supply scheme.
These significant engineering accomplishments have enabled Perth to become the successful, vibrant place that it is today.