NZTA set to double use of life-saving 'rumble strip' road


The NZ Transport Agency is set to more than double the length of the state highway network fitted with life-saving 'rumble strips'.

The NZ Transport Agency is set to more than double the length of the state highway network fitted with life-saving 'rumble strips'.

Formally known as ‘audio tactile profiled markings’, rumble strips are raised road markings used along road edges and centrelines. When vehicles drive over the markings the rumbling effect acts as a wake-up call, alerting drivers that they are veering out of their lane.

The NZTA’s new national installation programme will see approximately 750 additional kilometres of state highways across New Zealand fitted with rumble strips by the end of June 2009. This will increase the total length of the state highway network fitted with rumble strips to approximately 1,350 kilometres.

The new rumble strip installation programme has been expanded by approximately 50 percent due to additional funding for state highways being made available through the Government’s Jobs and Growth plan.

Every year dozens of New Zealanders are killed and hundreds more are injured in crashes when drivers drift off the side of the road or stray across the centreline into oncoming traffic. While several factors can contribute to this type of crash the increased use of rumble strips has the potential to prevent many of them from happening.

New research has pointed strongly to the safety benefits offered by rumble strips, particularly in reducing crashes caused by driver fatigue and inattention.

“Tired drivers die and running over rumble strips may be a sign for drivers that they need to take a rest. This is an investment in making our roads safer,” said Colin Crampton, NZTA’s Group Manager Highways and Network Operations.

The New Zealand Road Assessment Programme (KiwiRAP)1 has identified rumble strips as one of the most cost effective road safety improvement tools available, with the potential to reduce injury crashes by 20 to 45% in the locations where they are installed.

High-risk stretches of road will be targeted first including those with a high incidence of crashes or high traffic volumes. Other state highways with above-average levels of crashes caused by fatigue or inattention, such as roads that are used for long-distance travel and/or by tourists, will also be targeted. Most commonly, they will be laid along road edgelines.

“As well as preventing crashes where drivers run off the side of the road, rumble strips along edgelines can also prevent head-on crashes, as many of these result from vehicles first leaving the side of the road, then over-correcting and crossing the centreline,” Mr Crampton said.
On some busier roads with high incidences of head-on crashes centreline rumble strips will also be installed. They will be placed on top of or alongside edgelines or centrelines, protruding from the painted line, creating a tooth-like effect that will be visible to all road users.

All road users have been considered in designing the installation programme. Where possible a 1m sealed shoulder will be maintained outside of the rumble strips for cyclists. Rumble strips also help improve the separation between cyclists and motorists.

Continuous installation of rumble strips along a significant length of highway will be favoured over a series of localised or spot treatments at crash black spots. This makes for a more consistent road environment, meaning warnings for drivers straying from the correct lane may occur some distance before the location of a potential crash.

“New Zealand motorists will see rumble strips being installed on many parts of the state highway network. The NZTA is excited to be getting this important work underway, and we are confident that it will ultimately save lives and prevent injuries on our roads.” said Mr Crampton.

1KiwiRAP is a road assessment programme managed by New Zealand Automobile Association in partnership with the NZTA, Ministry of Transport, Accident Compensation Corporation and the New Zealand Police. It uses different methods to measure a road’s safety, including risk maps based on the crash history of a road and five-star ratings based on a road's engineering features.

For more information contact:

Andy Knackstedt
NZTA Media Manager
(04) 894 6285 or 0212 763 222