HAPPY NEW YEAR! Australia welcomes 2018 with a bang

Australia has welcomed 2018 with a bang as millions of revellers took to the streets to enjoy a string of spectacular firework displays across the nation.

Sydney's family-friendly 9pm fireworks kicked off the action and whetted the appetites of those hanging around for the showpiece three hours later.

Over one million people crammed into the CBD with many hugging the Harbour shore in a bid to get the best view of the record-breaking display.

The spectacle included a rainbow waterfall off the bridge to celebrate the gay marriage vote and the upcoming 40th anniversary of Mardi Gras.

For the first time, fireworks formed the numerals 10 to one on the Harbour Bridge as the word "Sydney" spread across the arch.

An eye-watering one billion viewers were expected to have tuned in on TV and the internet to catch a glimpse of the $7 million spectacle.

Lord Mayor Clover Moore said the City of Sydney had worked closely with NSW Police to make sure the world-famous show is a success.

"There are extra (security) measures tonight, but there's no particular concern, they're just measures that are being taken because of the sorts of things (terrorism) that have been happening around the world," Ms Moore told reporters.

"We have always had a really fabulous, very safe event, and that's what we're counting on doing again tonight."

However it wasn't plain sailing for all after crowds were evacuated from a NSW Central Coast beach after a fireworks display went horribly wrong.

Witnesses posted photos and videos and described on Twitter how a barge caught fire during the 9pm fireworks at Terrigal, sparking scenes of chaos.

NSW Fire and Rescue says the two technicians were helped by onlookers before being treated by paramedics.

Melbourne's celebrations came amid heightened security, 10 days after a deadly car attack near Flinders Street station.

Police officers were out in force throughout the city ensuring revellers enjoyed the celebrations without any significant trouble.

More than $2.6 million was spent on 14 tonnes of fireworks, with around 500,000 people enjoying free entertainment and food stalls at several hotspots including Treasury Gardens, Kings Domain, and Docklands and Flagstaff Gardens.

In a similar move by Western Australia police, more than 1000 police officers were deployed across Perth for New Year's Eve to ensure the safety of partygoers.

Police Minister Michelle Roberts had said there would be a strong police presence for the evening despite the city not celebrating as spectacularly as Sydney with its major fireworks display.

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"Our major fireworks event is on Australia Day rather than New Year's Eve," she told reporters on Sunday.

Despite earlier storms disrupting the day's proceedings, Brisbane was out in force as crowds gathered at some of the best vantage points across the city to view the fireworks at South Bank and Kangaroo Point.

The city's foreshore was packed with people enjoying two spectacular sets of pyrotechnics at 8.30pm and then midnight.

Thousands more filled Adelaide's Elder Park, which took centre stage for the city's New Year's Eve celebrations.

Australia's capital saw more than 30,000 fireworks at City Hill in an impressive spectacle in Canberra.

And Hobart carried on the tradition of spectacular waterfront displays with thousands enjoying a $65,000 showpiece.