Even after one of the most consistently wet Perth winters on record, WA’s dams are experiencing below-average rainwater intake for the year to date, according to the Water Corporation.

Water Corp Media Specialist Dean Stacey said based on long-term averages, the state’s dams should have collected about 280 billion litres of water so far in 2021, but have fallen well short of that.

“This year so far WA dams have collected around 99 billion litres of water up to now – that’s a shortfall of near 180 billion litres,’’ Mr Stacey said.

He said WA was becoming increasingly reliant on desalination to make up for decreasing rainfall and hotter, drier summers.

“In the metro area 43 per cent of the drinking water supplied is desalinated sea water, while groundwater makes up 40 per cent,’’ he said.

‘’Fifteen per cent is from rainfall and a small amount is recycled and processed wastewater.’’

Although desalination is inevitable for our growing population Mr Stacey said, WA compared to the rest of the country is heading towards near full reliance on process sea salt water.

“Australia has a total of six desalination plants around the country, with WA housing two and even heading towards having to construct a third as the demand for water increases with population growth”.

Future forecasts of predicted rainfall look to suggest WA will continue to become drier and hotter said Mr Stacey.

“Rainfall in WA has decreased by 15 per cent since the 1970’s and is expected to decrease by another 15 per cent by 2030,” he said.

The Australian Bureau of Meteorology’s latest climate outlook update showed that southern WA is expected to experience below median temperatures and above average rainfall for the months leading into summer.

The official BOM outlook for the summer months will not be released until towards the end of November.

Leave a Reply