The most Liberal-party friendly state in Australia has been completely recast as a Labor fortress with Mark McGowan's election as premier being described as the greatest victory in the party's history in WA.
The repercussions of the astonishing rout were being realised on Sunday, with Labor expected to win about 40 of 59 seats, up from just 20 before the election.
The Liberal party suffered a 16 per swing and was halved, going from 31 to about 13.
Several ministers have lost seats including John Day (health), who has been an MP for 24 years, Albert Jacob (environment), Paul Miles (local government) and Andrea Mitchell (child protection and mental health).
The Liberals biggest project, the $1.9 billion Perth Freight Link will be dumped, despite work having started and $450 million in contracts being signed.
The Liberals' proposed $11 billion privatisation of 51 per cent of Western Power is also out.
Labor's near $3 billion Metronet rail plan for Perth is in but contingent on getting at least some of the $1.2 billion in federal funding meant for the freight link, which Prime Minister Malcolm Turnbull says it can't have.
Labor will order a Commission of Inquiry to find out exactly how the once-boom state fell into such dire financial trouble, probing government contracts and "secretive" deals to explain cost blow-outs and record debt and deficit.
Mr McGowan says getting the state's economy and budget back in order is his top priority after the Barnett government's "appalling" financial management including debt headed for $41 billion.
"We have a serious financial situation in Western Australia and a serious economic situation," he told reporters from his home and electorate of Rockingham.
He insists his government will act in the interests of everyone, amid worries about union influence, public service job cuts and Labor's ability to pay for $5 billion in promises.
He vowed to be "forceful and unrelenting" in dealing with Canberra, particularly over negotiations on the GST with WA's share a paltry 30 cents in the dollar, well below the other states.
However his own party has not offered to do anything about it, with federal Labor leader Bill Shorten unwilling to commit to change the GST distribution system when asked over the weekend.
Liza Harvey and Joe Francis have emerged as contenders to take over the leadership of the WA Liberal party, with Colin Barnett expected to step down.
There will be a lot of Liberal soul searching with much of the focus so far on a failed preference swap deal with Pauline Hanson's One Nation party, although the "it's time" factor, given Mr Barnett's longevity, is regarded as more relevant.
One Nation received a primary vote of just 4.7 per cent, below the Greens and Nationals and less than half what had been predicted only weeks ago after a messy end to the campaign.
However the party's expected to have at least one upper house MP in Colin Tincknell.
The Liberals alliance partner, the Nationals, is expected to retain only five lower house seats, down from seven. Leader Brendon Grylls is struggling to hold on to his Pilbara seat.
