Otago roads - safe or not?

By David Thomson on Sat, 12 Aug 2017

Should we be relieved or disappointed that just one lower South Island road features on the Automobile Association's recently released list of New Zealand's 10 most dangerous highways?

The methodology used to assemble this list involves compiling serious accident rates per kilometre of highway over five years. It will tend to place substandard highways that carry high volumes of traffic ahead of substandard highways that carry low volumes of traffic; no surprises, then, that stretches of highway in the more populous North Island dominate the top 10.

A rating compiled on this basis is probably quite useful for suggesting where our national roading authorities will get the best bang for their buck improving highway quality. The down side is that roads that carry less traffic by national standards - which will include most roads in this part of the world - will be less likely candidates for improvement.

The roads identified this week are, I think, those that have been awarded the highest National Risk ratings under the latest (but not yet publicly available) KiwiRAP (New Zealand Road Assessment Programme) evaluation.

It is interesting to note that several of the roads in this week's top 10 were rated in the highest National Risk band in the previous (2012) KiwiRAP assessment. In that assessment, no roads in Otago were placed in the highest National Risk band.

The 2012 assessment also included a Personal Risk assessment, which adjusts the risk assessment for traffic volumes. This is actually the more relevant assessment of risk for you and me as actual road users.

On that assessment, two Otago roads were assessed as high risk, and a third made the list of the 30 worst roads for Personal Risk. I suspect the AA's comments this week are a prelude to a full release of the latest KiwiRAP results.

These results will, I am sure, show our highways in less positive light than this week's news implies. Incidentally, KiwiRAP also runs a star rating system for our highways, classifying them on a five-star scale on the basis of safety design elements such as lane and shoulder width and the presence of safety barriers.

When this was last done back in 2010, the lowest awarded rating of two stars was given to 30% of Otago's highway network; 69% received three stars, and just 1% (basically, Dunedin's Southern Motorway) four stars.

No roads, either nationally, or here in Otago, managed a five-star rating. That's food for thought too, as we ponder the detail of road safety.

David Thomson