Are our highways getting safer?

26 of the 35 highways received significant safety improvements between the observation periods. The highways that had the larger scale safety upgrades, like the building of bypasses, partial bypasses and significant lengths of median and side barriers, saw fatal and serious injuries drop by an even higher margin: 28.4% on average.

“In real terms there are about 20 less fatal crashes happening every year on our most dangerous highways compared to 15 years ago. And that drop has happened despite traffic increasing 50% between 2009 and 2023,” says AARF Programme Manager Christopher Stachowski.

He says nine roads had crash reductions of at least 50%, while three additional highways registered drops between 44.9 % and 47.1%.

1. SH20B to Auckland Airport (86% reduction). 
2. SH2 Bethlehem to Mount Maunganui (78% reduction). 
3. SH1 from SH74 to SH73 Christchurch (64% reduction). 
4. SH1 Dunedin to Mosgiel (62% reduction). 
5. SH2 Napier to Hastings (60% reduction). 
6. SH2 Bay View to Napier (57% reduction). 
7. SH1 Pukerua Bay to MacKays Crossing (55% reduction). 
8. SH2 Pokeno to Mangatarata (51% reduction). 
9. SH2 Mount Maunganui to Paengaroa (50% reduction). 

1. SH1 Cambridge to Piarere (75% increase).
2. SH2 Katikati to Tauranga (44% increase). 
3. SH1 Marsden Point (SH15A) to Whangarei (23% increase). 
4. SH1 Auckland to Takanini (23% increase). 
5. SH17 Albany to Silverdale (5% increase). 
6. SH2 Wellington to Upper Hutt (4% increase). 

Christopher says while these roads showed no net improvement, when crash rates were compared with the growth in traffic volumes the situation did look better for some.

For example, SH2 Wellington to Upper Hutt increased from 56 serious and fatal crashes in the 2002 to 2006 period to 58 in 2017 to 2023. Between those spells the average daily use of the road nearly doubled from 20,621 vehicles per day to 37,008, and the number of fatal crashes fell from 12 to two.

“Not all roads got a brand-new bypass or a full redesign, but smaller scale upgrades are still valuable. Safety measures like the wire rope barriers installed near Upper Hutt can’t be expected to eliminate crashes, but they do prevent head-on collisions, slow vehicles that have lost control, and reduce the number of vehicles leaving the road. In this case fatal crashes have reduced 83%.”

Christopher says being able to track the safety performance of New Zealand’s state highways is hugely valuable.

“It’s important to remember that the figures here represent people – low numbers or high, increases or decreases, they show whether or not someone has been able to get home safely and continuing living their life. This research is an important insight into how we can best use our resources to reduce deaths and serious injuries and make our roads safer.”