September water use to date

16 billion litres

17 billion litres

Dam storage levels



Cumulative streamflow into dams

145 billion litres

(Post 1975 May to September average)

114 billion litres

September rainfall to date

87.0 mm

(September mean rainfall 1994-2017)


81 mm

(September average rainfall 1876-2016)

28.8 mm

Note: 1 billion litres = approx. 400 Olympic swimming pools.  Please note these figures are rounded (except for rainfall) to the nearest whole number.


Water use


Average daily water use over the last week was 683 million litres, which was above the forecast of 595 million litres.  Since 1 July 2018 we have used 54 billion litres of water - this is about 4 billion litres above what we had forecast.


Dam level (total for 15 dams)


The dam storage level has increased by 250 million litres over the last week and they are at sitting at 59%* of full capacity.


*Please note some dams are filled from different sources and this increase may include the transfer of groundwater and desalinated seawater from treatment plants as well as streamflow (that comes from rainfall).  The percentage of full capacity number can also go up or down depending on how much water has been supplied to customers this week from dams.


Streamflow (total for 15 dams)

From 1 May 2018 to 27 September 2018 the dams have received 114 billion litres of streamflow.  The post-1975 average for the May to September period is 145 billion litres.


Sprinkler roster compliance

The summer sprinkler roster now applies but there’s no need to rush out and turn your sprinklers on as gardens are still getting plenty of water from rainfall. Our team of inspectors issued 92 warnings and 33 fines this week.  Since 1 January 2018, we have taken a total of 6431 actions (warnings + fines) compared with 7458 actions for the same period in 2017.


Annual rainfall

Perth has received 693mm of rainfall since January this year.  The cumulative average rainfall for January to December is 732.8 mm. 


General water news

When the sun comes out, the sprinklers come on!

It’s as predictable as night and day for Water Corporation each Spring, because we know from many years of experience that Western Australians’ water consumption skyrockets as soon as hot weather returns.

As a flow-on, our inspectors suddenly get a lot busier. Last week’s sunny, warm weather saw the rate of fines and infringements pretty much double, as people failed to comply with set sprinkler watering days.

Two weeks ago, we issued 15 $100 infringements and 63 warnings, but the stats jumped massively to 33 infringements and 92 warnings this week in the metro area. Before you ask, no, we didn’t have more inspectors out and about, nor were they doing their job differently!

Yes, the seasonal watering roster is back. You may only water your garden two days a week, or three if you’ve got a bore. You can easily check your watering days on this website by putting your street number and postcode into the watering days app.

Don’t forget, too, that you are only permitted to water once each watering day, before 9am or after 6pm, so evaporation is minimised. 

Sprinkler rosters were first introduced in 2001, then made a permanent water efficiency measure across the state in 2007, so they’re certainly not new. If you’re unsure what your watering days are, it might be time to check again online.

Thanks for doing your bit to preserve our precious water resources!

Media Enquiries:

Contact: Neil Stanbury

Phone: (08) 9420 2555