Trees will be trimmed or removed to improve visibility, and guard rails will be installed on State Highway 5 Waiotapu, State Highway 30 Whirinaki Valley, State Highway 36 Kaharoa Rd and SH5 Tutukau Rd, Mihi.
"The guard rails are being installed on corners where there is a risk of people losing control and driving off the road," Mr Johansson says.
"Half of the death and serious injury crashes in New Zealand are from drivers losing control and running off the road. A guard rail that keeps vehicles on the road can mean the difference between someone walking away from a crash or being taken away by an ambulance or in a hearse."
Putting in place measures that help prevent road crashes from occurring is a major focus for the Transport Agency, Mr Johansson said.
"However, no matter how many measures we develop, mistakes will still happen and road crashes will occur."
"Installing guard rails, removing hazards such as trees and creating a more readable road with upgraded signs and road marking help to create more forgiving roads and roadsides that reduce the impact if a driver makes a mistake and crashes."
The SH5 Tutukau Rd site was finished early this month, and the remainder of the works are under way and will be finished by mid-June. Motorists are advised to drive with care through the work sites.