Motorists are still facing delays almost 18 hours after a fiery crash between a truck and a mobile crane on the M1 Pacific Motorway.
The B-double truck was engulfed in a fireball following the collision with the crane near the Pacific Highway overpass at Brooklyn, just south of the Hawkesbury River Bridge, about 4am on Tuesday.
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Fiery truck crash north of Sydney
A crash between a truck and a mobile crane has closed the north-bound lanes of the M1 Pacific Motorway north of Sydney, causing delays for motorists. Vision: Nine News.
Through the afternoon, traffic on the major motorway remained chaotic, with drivers warned to expect an ugly afternoon peak. There was no forecast on when the road would re-open as normal.
The truck and the crane involved in the crash have been removed, however the road surface is significantly damaged and crews are figuring out how it can be repaired.
Just before 2pm, as an "extensive and complex salvage operation" continued, traffic was queued northbound on the Pacific Highway for 19km from Asquith.
At 5.45pm, in the height of the afternoon peak, traffic remained "heavy" in both directions on the highway.
A queue stretched for 17 kilometres northbound on the M1 Pacific Motorway, with a queue of 2.5 kilometres southbound.
BROOKLYN: Continue to avoid M1 as cleanup continues after truck crash. Northbound using 2 southbound lanes. Southbound diverted at Mt White. pic.twitter.com/T01zCS9NL2
â Live Traffic NSW (@LiveTrafficNSW) January 31, 2017
For most of the afternoon, northbound motorists were directed into two southbound lanes of the motorway at Cowan, with a reduced speed limit of 40km/h.
Southbound motorists were diverted onto the Pacific Highway at Mount White, rejoining the motorway at Berowra.
Just before 9pm, all northbound lanes of the motorway were closed, with northbound commuters also diverted onto the Pacific Highway as crews continued repairing the road.
Commuters needing to use the motorway were advised to bring water with them and check their fuel - or to catch a train instead.
Buses travelling between Berowra and Brooklyn were delayed up to 40 minutes due to the heavy traffic.
Earlier on Tuesday, firefighters handed bottled water to drivers who were caught in the clogged diversions along the Pacific Highway.
As traffic sat at a standstill, some motorists took to social media to say how long they had been sitting on the motorway. Several people said they were queued northbound for more than 5 hours before contra flows began to clear the traffic backlog.
Newly-installed minister Melinda Pavey has traded barbs with Labor over the incident, after shadow minister Jodi McKay demanded an explanation for why it took almost 10 hours to set up the contra flow.
Ms McKay labelled the delays a "disgrace" and a "ministerial bungle".
"This is yet another ministerial bungle that has left thousands of people trapped in searing heat on the M1," Ms McKay said. "Melinda Pavey has failed her first test as Minister for Roads."
In a statement on Tuesday afternoon, Ms Pavey - who was appointed minister just two days ago - thanked commuters for their patience.
"Labor's suggestion that a contraflow should have been put in place this morning is an attempt to politicise a serious accident and shows blatant disregard for driver safety," Ms Pavey said.
"If a contraflow was in put in place this morning as Labor suggests, it would have resulted in traffic chaos, with the majority of morning traffic travelling southbound. Jodi McKay should get her facts straight before cheaply putting the lives of commuters at risk."
A NSW Police spokeswoman said the truck and the crane were heading north when they crashed. The vehicles were extensively damaged, and were blocking all north-bound lanes between the cliff face and the median strip.
The cause of the crash was not yet known, but a witness claimed one of the vehicles had jack-knifed.
The blaze also spread to the scrub on the median strip, and caused significant damage to the road surface, police said.
Remarkably, one of the drivers escaped uninjured, while the second was taken to Gosford Hospital with only minor injuries.
"The drivers of both vehicles are extremely lucky to be alive," said Inspector David Hogg, from the Ku-ring-Gai Local Area Command.
Motorists caught in the traffic jam should avoid making dangerous and illegal U-turns, police said.