Sydney revelry mostly sensible: police

It was a fairly peaceful night of New Year's Eve celebrations in Sydney, with police making just 30 arrests out of the 1.6 million people who flocked to the city.

Revellers were treated to a spectacular show at midnight on Thursday, with bursts of colour shot into the sky from several sites across the foreshore, as a colourful waterfall of sparks cascaded over the Harbour Bridge.

Among those who misbehaved during the festivities were a 57-year-old man who allegedly made a hoax bomb threat on Sydney's North Shore just after midnight.

Another man was also arrested for allegedly throwing a bottle at a police officer's head during an incident at a Shalvey service station in the city's west around 1am.

Police say the officer received a cut to her head and is recovering in hospital in a stable condition.

Officers also broke up several brawls in Leichardt and Balmain in Sydney's innerwest and a 21-year-old man was arrested for allegedly threw a bottle at a police vehicle.

At least half of the other arrests made during their biggest operation, which included 2500 additional officers, were drug related, police said.

Despite prime vantage spots filling up quickly on Thursday afternoon, police said none of the crowds got out of hand.

"With only a few exceptions, the vast majority of people in the city for New Year's Eve behaved safely, sensibly and responsibly," Commissioner Fuller said.

The easing of lockout laws across the city also didn't cause extra problems, he said.

"With having 2500 additional police there was no threat to having the lockout laws relaxed for one night," Commissioner Fuller said.

Paramedics reported a busy night, taking more than 2700 calls for help across the state between 4pm News Year's Eve and 3am on New Year's Day.

NSW Ambulance Senior Assistant Commissioner Jamie Vernon said most of the calls related to violence or for patient's suffering extreme intoxication and related injuries such as falling from roofs.

Paramedics expected to continue to respond to incidents involving patients suffering from the effects of alcohol or drugs throughout Friday morning, he said.