The new limit changes will come into effect on June 25. New signs and markings along the highway will highlight the new lower speed limit and encourage drivers to slow down.
Recent serious crashes on SH10 north of the Kerikeri roundabout include a head-on smash on August 15 last year which left a woman and two young children seriously injured. Fatigue was thought to be a factor.
The woman was charged, as was a motorcyclist who drove through the accident scene and collided with a police officer.
On September 28, 2013, two young women were badly injured when the modified car they were passengers in rammed a car which had stopped at the scene of an earlier accident. A crash investigator put the car's minimum speed at 157-168km/h.
The women had to be cut from the wreckage and were flown to Whangarei Hospital. Both suffered broken legs and one a broken back. The driver was sentenced to eight months' home detention and disqualified from driving for two years.