Metro region weekly water update for 29 September 2017

Perth to expect long hot summer

Sky News Weather has released its Severe Weather Outlook report, which predicts WA is in for a hotter and drier summer than last year.  The Report states that the ongoing heat anomalies of recent years will almost certainly continue as global warming becomes an ever more prevalent background influence on Australia’s climate.   It is expected that the coming summer will be the 12^th consecutive warm season with above average temperatures.  One or two heatwaves will affect Perth in the six-month period.

Water use

Our average daily water use last week was 574 million litres, which was below the forecast of 658 million litres per day.  This water was used by the two million people who are connected to the Integrated Water Supply Scheme, which delivers water to Perth, parts of the south west, Agricultural and Goldfields regions. 

Our financial year to date water use is 52.7 billion litres – right on track for the 52.7 billion litres we have forecasted. 

Dam levels

Over the last seven days Perth’s dam storage levels increased from 42.8% to 44.2% (1.4 percentage points).  This was partly due to them receiving almost 8 billion litres of inflow from streams thanks to the wet weather over the Queen’s birthday long weekend.  This brings the total streamflow to 75 billion litres since 1 May 2017.  The post-1975 average for annual streamflow is 189 billion litres.  It is worth noting Perth’s dams also store ground and desalinated water that is transferred from our treatment plants.

Sprinkler roster compliance

The two-day-per week Sprinkler roster now applies, and this week our inspectors issued 25 warnings and 16 fines in the metro region.  This is compared to 46 warnings and 33 fines the previous week.   Year to date we have taken a total of 8,486 actions (warnings + fines) compared to 9,014 actions for the same period in 2016.    

Rainfall

So far this September we have received 71.4mm of rainfall compared to the average monthly rainfall for September of 81.3mm.  Although it feels like we’ve had a lot of rain in September this year, it’s actually about the same as last year (68.6mm for September 2016).

Since 1 January 2017 we have received 760.6mm of rainfall compared to the cumulative average of 759.4mm (January to September).

General water news

Don’t know your gigalitres from your megalitres?  Well here’s a handy conversion…

One gigalitre = one billion litres

One megalitre = one million litres

One kilolitre = one thousand litres

One kilolitre of water = one tonne