Motorists will be under stricter controls this summer with the threshold for speeding reduced for the next two months.
The summer push began on Sunday and Northland's Road Policing boss Inspector Murray Hodson said drivers appeared to be paying attention.
Until January 31 police will have a tolerance of just 4km/h above the speed limit for all drivers and it is the first time the reduced speed tolerance has been extended beyond an official holiday period.
Mr Hodson said the cause of many serious injury and fatal crashes in Northland was speed.
"Research tells us that a 5km/h reduction in speed means a 10 per cent reduction in serious injuries and a 20 per cent reduction in fatalities on the road," Mr Hodson said.
Northland's road toll stands at 20 but the summer period traditionally sees an increase in serious or fatal crashes.
Out on some of the region's high-risk roads yesterday most motorists were abiding by the reduced tolerance.
One woman, stopped doing 69km/h in a 60km/h zone on Kioreore Rd, admitted knowing about the reduced speed and said she had not been paying attention.
Another driver on SH1 near Mata was caught doing 110km/h. However, Mr Hodson was rapt most drivers seemed to be were obeying the posted speed levels, including travelling through road works.
"Drivers may slow down for road works, but still be over the temporary speed limit, so we will be enforcing those areas as well. Many of the road work areas have patches of gravel and drivers can lose control.
"They can end up injuring or killing road workers as well as themselves."
The 4km/h speed tolerance was introduced at Queen's Birthday Weekend in 2010 and has been used for all holiday weekends since.
"It's an excellent tactic and will work in reducing the number of serious crashes and fatalities in Northland. If people know they will be ticketed for being 4km/h over the limit then ultimately it will start to change people's driving behaviour which will in turn reduce the number of victims."
Drivers can expect to see numerous police checkpoints across the region and every motorist who is stopped will be breath tested.
Mr Hodson encouraged those who witnessed dangerous driving to call police on *555.
"All calls made to *555 will be acted on and people breaking the road rules can expect an infringement notice or be stopped by a police officer."
Mr Hodson said police would also use the "spot and stop" tactic, where an officer would be spotting poor driver behaviour and another officer further along the road would stop the offending driver.