The new hours have already had an impact on JR's Bar & Grill, which is known as the go-to "late night" bar in Rangiora.

Locals fear Waimakariri will become the "sleepy hollow" of Canterbury when it adopts the strictest closing hour regulations in the country next week.

Under the Waimakariri District Council's new local alcohol policy, bars, pubs and restaurants would be unable to serve alcohol after 11pm from Sundays to Thursdays and after 1am on Friday and Saturday.

Off-license retailers would be unable to sell alcohol after 10pm.

The restrictions, which come into effect on May 16, would be the most severe in the country, and out of step with elsewhere in Canterbury - Hurunui opted for 2am closing each day, and Christchurch for 1am each day, or 3am for some places in the central city.

Rangiora publicans are slamming the "unfair" rule change, warning of job losses and a deluge of patrons leaving town.

It had already led to two job losses at busy Rangiora bar JR's Bar & Grill, and would cripple its late night social activities during the week, said manager Michelle Fahey.

"It's becoming a wee bit of a nightmare, actually… It's impacted on the business a lot," she said.

It had already implemented the new hours ahead of the rule change, and Fahey said the effect had been notable, as JR's was the go-to 'late night' bar in Rangiora.

The 11pm closure had affected its darts and pool tournaments, which it held in conjunction with pubs around north Canterbury, and had seen it lose some regulars to establishments "across the bridge" in Christchurch.

Fahey said young locals would likely take to drinking at home or in public if there were no bars for them to go to.

"At least you know if they're in the bar there's supervision going on. If you close this bar at an early time, where are the young ones going? They're going to your parks, drinking at their homes.

"I think the writing's on the wall. There will be trouble in Rangiora when the young ones have nowhere to go when they're not supervised and not in a controlled environment."

The policy change was supported by the police and the Canterbury District Health Board.

In a submission to the council by Canterbury police district commander Gary Knowles, he said local alcohol policies were "potentially the single biggest crime prevention tool this generation," and restricted hours would likely reduce crime in the district.

Because of inconsistencies across the region, pubs "virtually across the road" from each other would have different closing hours, said Monteith's Rangiora manager Bob Blair.

"It's pretty unfair to the people in the district with the earlier hours. It's a bit of a no-brainer where people are going to go if they want to stay out a bit later," he said.

The 11pm closing would make events such as New Year's Eve or late night sports matches impossible without a special license, which wouldn't be worth applying for, he said.

He could not figure out why Waimakariri had more limited hours than elsewhere in the country.

"Where's the justification for going to 11pm for goodness sake? That's what I'd like the council to say. If it was 1am seven days a week we'd live with that.

"But this 11pm thing, I don't know where it's come from or why they're so hell bent on doing it."