With up to 20,000 revellers expected to spill onto Kings Cross streets at the same time every Friday and Saturday night under proposed curfews, police are bracing for a surge in dealing with intoxicated partygoers.

The mandatory eight-year jail term for a one-punch attack resulting in death by an intoxicated person comes into effect this weekend.

Further measures, such as the 1.30am lock outs and 3am last drinks, are expected to be passed through parliament next month and in effect by April at the latest.

Kings Cross Superintendent Michael Fitzgerald expected the numbers of punters put into sobering-up centres to rise in the red light district once the curfews are in place.

“I would be very surprised if it did not increase just because of the issues with more people being on the streets between 3am and 3.30am,” he said.

He said police will have to adjust to dealing with larger crowds but officers are up to the job.

Kings Cross was the site of the two prominent fatal one-punch assaults that lead to the reforms by the state coalition government.

The peak trouble time for police in the nightclub district is between 4am and 6am, just after the planned shutting of doors at 3am.