Two weeks ago, and as part of an ongoing series about transport planning, investment and outcomes, I wrote about the road toll.

In that period a further 15 car occupants have died, including four people north of Taupō this past Tuesday.

That accident occurred at the intersection of Tutukau Road (running East to West) and State Highway 1 (running North to South) as marked on the map below.

Waikato councils put forward that section of State Highway 1 between Wairākei and Ātiamuri as a candidate for safety improvements. In 2015, the NZ Transport Agency tagged the project as ‘probable’, meaning that the project would likely progress if funding was available.

Funding was due to begin in 2015/16 for preparing a business case, and continue through to 2017/18 with construction. It appears that the project is yet to receive any funding.

We can’t say what factors contributed to this crash. Nor can we say whether safety improvements on that stretch of road would prevent similar accidents. We can, however, say that these are not hypothetical lives. And these are not hypothetical projects.

Safety is an important aspect of transport for many travellers. The country should be debating whether we have the mix right between safety and other features of transport we care about including travel times, resilience, access and choice.

If we, as communities and as users of transport, are unhappy with what we’re getting, we should be asking whether government and its agencies should be the ones deciding for us.

Today I want to respond to some of the coverage of the road toll over the past two weeks and to tease out these issues more.

The road toll is definitely increasing

Several commentators questioned whether the road toll is increasing given that population has increased since 2013.

The NZ Transport Agency was among these, telling Radio New Zealand: “There’s definitely a trend up but equally there are more people driving. The amount of kilometres that people are driving in their cars has risen by about 10%, 15%.”

This view is mistaken.

As I noted in my previous article, the fatality rate (deaths per kilometre driven across New Zealand) of car occupants is 41% higher in 2017 than it was in 2013.

Another way of looking at this is that, while New Zealand is driving 15% more as a country than in 2013, deaths are up 60%.

Had we kept fatality rates at 2013 levels, there would be about 80 fewer deaths than we expect there to be in 2017, and over 110 fewer since the end of 2013.

These changes are, in technical terms, statistically significant. We can have greater than 99% confidence that the road toll is up.

Some regions are faring worse

While the long historical downward trend in the road toll was apparent across almost all regions, the increase of the past few years is not. Increased safety risks appear to be concentrated in the Upper North Island regions of Waikato, Bay of Plenty, Auckland and Northland and the lower South Island regions of Otago and Southland.

The chart below shows those regions where the risk appears to have increased since the national-low road toll in 2013.

Why is the road toll increasing?

I don’t know. And it looks like no one does.

Commentators have suggested plenty of plausible factors (such as distractions from smartphones and reduced focus on fixing dangerous roads), as well as some less plausible factors.

The Police have put it down to driver behaviour. They’ve ruled out a lack of funding as a factor.

The Police’s position will come as a surprise to the Police who, in February, told The Otago Daily Times that funding issues were why 12 New Zealand regions have been without fixed speed cameras for 18 months.

To really understand what’s going on requires robust statistical analysis.

The Ministry of Transport has undertaken at least three studies into the road toll since 2013 for various purposes. Methodological issues mean that these studies cannot be used to explain the increase. One study says the biggest factors affecting the road toll are petrol prices and wages. Petrol prices and wages affect how much we drive, less so the chance of dying once we’re on the road. The solution to the road toll is not higher petrol prices or lower wages.

According to people I’ve spoken to recently, the Ministry commissioned a fourth study that was due to be completed in March 2017. It is yet to be released.

Those same correspondents are looking at undertaking their own research. I look forward to the contribution this will make to the public debate.

Could New Zealand be doing more?

Yes. Proposed improvements between Wairākei and Ātiamuri in Taupō show there are other projects out there that could be pursued.

The question is whether these interventions and investments are worth it relative to the other transport choices we have, such as transport to support new housing developments.

In interviews about the road toll, the NZ Transport Agency has talked up the safety benefits of the Roads of National Significance. However, as I noted in my previous article, these seven roads are relatively lightly travelled compared to the average $1.6 billion each cost. And $1.6 billion could buy a lot of road median barriers and road safety ads.

Where to from here?

The public debate that has erupted over the past two weeks is welcome, though it is sad that it took horrific accidents and many lives to trigger it.

What we now need is a structured and responsive way to address these issues. Different safety interventions have different impacts, and safety isn’t the only aspect of transport we care about. Focussing on one aspect at a time risks swinging too far from other important objectives.

In my next piece for Interest.co.nz, I’ll set out current planning processes and how the public can be involved. I’ll also start to look at how that process could be reformed.