New research has found that a third of fatal or serious crashes at New Zealand’s 1800 rural crossroads happen because drivers are missing crucial cues and that simple measures could put the brakes on the unnecessary loss of life.

The Automobile Association Research Foundation (AARF) describes the crossroads where these crashes happen after a driver has failed to detect the intersection as “invisible killers”. The resulting carnage is far from invisible to many police officers.

Police Association vice-president Steve Watt, who is also the senior sergeant managing Otago Lakes Road Policing, says the findings of the research commissioned by the AARF are not surprising but they are “a positive step forward”. 

“We know crossroads, particularly in the rural setting, are high-risk. All too often I have seen drivers failing to give way and/or stop at these intersections, putting themselves and others in danger,” Steve says. “It’s association members like me who see the often life-altering consequences.”

Even after nearly 25 years in Police, one of the hardest parts of the job is attending fatal crashes, he says. “Then you have to tell families that a mistake means their loved ones won’t be coming home. It’s heartbreaking for them and for us. It doesn't matter how hardened as a police officer you are, you never quite get over the horrific scenes and the fact they are so often avoidable.” 

AA road safety spokesman Dylan Thomsen says needless loss of life is what prompted the AARF to commission human systems research specialists Mackie Research to dig deeper into the causes of “failure to detect” crashes and potential solutions.

The researchers analysed 305 rural crossroads crashes using Police serious crash unit reports. They noted that many crashes occurred on roads with common characteristics which led to crucial cues being missed.

“Many of the roads were high-speed areas with long straight sections and light traffic. Visibility of upcoming intersections and bisecting roads is often poor, and signage and markings can be minimal. They also commonly feature rows of trees or poles that can trick the eye into focusing straight ahead,” their report says. 

The Mackie researchers also tested whether introducing inexpensive safety improvements could influence driver behaviour at rural crossroads. 

Research participants watched footage of real rural roads in New Zealand – each with different warning markings. One video featured the standard crossroad treatment of a single left-hand Stop sign while the other videos included additional treatments such as extra and larger signs or painted words or lines on the road as drivers approached.

The results showed that these extra road markings and signage used in addition to the standard treatment could alert drivers to an oncoming intersection up to 160 metres earlier. At 100km/h, this could buy a driver an extra six seconds of reaction time.

While it was beyond the scope of the research, road safety experts were asked what it might cost to install simple “failure to detect” mitigations to improve crossroad detection.

They said that adding gated (double) oversize Stop/Give Way signs, gated advance warnings signs, transverse rumble lines and better delineated reflective markers leading to the intersection would likely cost $25,000 to $30,000. It was also noted that the cost would probably reduce significantly if a few local intersections were packaged together.

“The researchers have done the work to prove that by implementing simple techniques we can have a massive impact on road safety,” Steve says. 

“Now it is up to local government and road authorities to put a plan into action. I urge the roading authorities to take a proactive step in introducing these low-cost options to save lives.” 

Dylan says AA is already sharing the findings with regional transport authorities to assist them in identifying rural crossroads where the common factors cited in the research create a heightened risk of a “failed to detect” crash and to show the difference that could be made by adding different types of low-cost improvements. – CARLA AMOS