Traffic Delays After Accidents

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Technofreak

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#324978 20-Jun-2026 11:07

There's headlines in this morning's news about the horrendous delays cause by the accident on SH1 north of Wellington last night. It appears the road was closed for over 6 hours. There are reports of of drivers abandoning their cars and reports of people walking across the lanes of moving traffic on the other carriageway. The risk of further death and injury IMO would have been very high.

This is a more extreme example but the number of these delays seems to have increased over the past few years. No doubt the increase in traffic has contributed but the major contributing factor seems to be the amount of time spent by the Serious Crash Unit to investigate.

These types of delays are a relatively recent phenomenon. Why the need for such disruption? Is the cure (the investigation time) worse than what it's trying to cure? I get the need to figure out what went wrong. However we seemed to be able to figure it out in the past without creating massive delays like was experienced last night.

If it's deemed to be absolutely necessary to have the road close for so long then there needs to be a plan to get the trapped traffic off the highway and onto secondary roads. It must be possible to have places in the median barrier to allow the traffic to be diverted onto one lane of the other carriageway. Just leaving vehicles and their occupants trapped for hours on end like this isn't acceptable in my opinion.

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tweake

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#3504804 20-Jun-2026 11:15

not sure why the back log of traffic was not cleared. had traffic accidents and they turned cars around on the motorway and got them off the off ramp.

however road accidents need investigation. its basically a murder investigation and no one wants that messed up. catch is kiwis have a bad attitude of "its just an accident".

geek3001

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#3504805 20-Jun-2026 11:26

Technofreak:

Just leaving vehicles and their occupants trapped for hours on end like this isn't acceptable in my opinion.

Couldn't agree more, it's ridiculous.

I presume the SCU treats the scene as a potential crime scene, so have to freeze all movement until they have gathered as much evidence as they see fit, however long it takes. Too bad for those stuck in the traffic mayhem that results.

BlakJak

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#3504886 20-Jun-2026 13:29

Serious Crash Unit has a process and it takes several hours to preserve the evidence required.

We also are usually not privy to the details - there may be complications at any given scene.

Keeping people stationary for that long does seem less than ideal, I was very glad to be working from home. The way this one was media covered suggests it was unusually bad, so I bet they're figuring out what went wrong and that they can do better next time, too.

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snj

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#3504888 20-Jun-2026 14:06

From: https://www.nzherald.co.nz/nz/police-nzta-defend-wellington-motorway-closure-after-fatal-crash-delays/DC2SAGIUCJGMNECXGZEKLUZXFE/

“The road was reopened as soon as police had completed gathering evidence, debris was cleared and damage to the road was repaired.”

I suspect many people forget that last part, you don't know exactly what happened.

But lets say for a 2-lane expressway section (not a regular to Wellington, so just thinking generally here), one of the vehicles is on it's side and digs up the road surface along the line markers, that's both lanes unsafe for use, the shoulders in the past aren't designed for continual heavy loads (changed a bit with some shoulders now doubling as bus lanes though), and you need room for the road crews to even do a temporary repair. Where exactly can people go? That's also after the police have taken their photos/etc (I recall they often return later under rolling stops to do some of their braking tests/etc), and debris, etc is removed.

Unfortunately in this one, someone did die after the fact. A lot of what they do for serious accidents, is as a precaution for this eventuality so they have evidence they can take to the coroner.

boosacnoodle

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#3504889 20-Jun-2026 14:09

Most people aren't privy to it but local authorities (your council) and NZTA (as required) oftentimes work with Police after a serious crash to understand the causes and work towards improvements that could help to reduce or prevent reoccurrence in the future. Without this process, it's likely that nothing would be learned and crash frequency could well increase meaning more delays.

elpenguino

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#3504890 20-Jun-2026 14:09

Technofreak:

If it's deemed to be absolutely necessary to have the road close for so long then there needs to be a plan to get the trapped traffic off the highway and onto secondary roads. It must be possible to have places in the median barrier to allow the traffic to be diverted onto one lane of the other carriageway. Just leaving vehicles and their occupants trapped for hours on end like this isn't acceptable in my opinion.

I narrowly avoided this mess last night - la penguina called me before I hit the area shortly after the crash and I went onto secondary roads.

I hate to think how bored, hungry and cold everyone got. From what I could see, there were massive delays in the northbound direction as well.

You've hit on a practical solution you see in other countries. Open the barriers in two places and turn one side into two way for a short distance. There will still be delays but at least some traffic will get through.

Can the authorities get organised to do all that and lay out thousands of cones in the middle of a serious crash and blocked motorway ? I'd like to see it.

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SomeoneSomewhere

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#3504902 20-Jun-2026 16:30

The section between Tawa and Churton Park/Glenside is basically all grass median with steel guardrail, most of it with 1-2m of height difference. You would have difficulty getting an off-road vehicle across even with the guardrail removed. Absolutely not an option.

The exception is right at the Glenside interchange where it's flatter with wire fence/cheese-grater, but still grass. It sounds like that section is pretty much where the crash occurred - I haven't seen any photos yet or driven it since the crash, but there was suspicion (incorrect?) that someone drove the wrong way down the shown exit.

Turning cars around in place or going through the accident site would have been the only options available. Probably could have at least sent a cop to walk/drive past the queue and provide an ETA/update.

For people north of the Tawa exit, detouring via Middleton Rd is an easy answer and presumably what they did - far easier and safer than trying to set up bidirectional flow against peak hour traffic. It's the people between Tawa and Glenside that have no good option.

MikeB4

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#3504938 20-Jun-2026 20:23

Securing the scene, dealing with victims and completing the scene investigation is and should be the highest priority.

Here is a crazy notion, lets give peace a chance.

pdh

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#3504986 21-Jun-2026 10:41

MikeB4:

Securing the scene, dealing with victims and completing the scene investigation is and should be the highest priority.

Sorry - but that comes across as channelling Constable Plod.

You've listed three tasks and (I think) called them all the highest priority.

I would hope that anyone actually involved - professionally - would treat the care of (not 'dealing with') the injured as the highest priority.

Scene investigation is and should be a lot less important.

If criminal charges may need to be laid - then yes, the scene needs investigation.

That does not mean that the health and safety of the rest of the population should be ignored.
On a really hot day, 6 hours in an not-air-conditioned car might well kill someone.
It's not hard to come up with other scenarios with serious harm as the outcome.

So the OP's concern does not deserve to be dismissed.
My experience makes me believe that our cops take a much longer time to clear many accidents than those in the UK or Canada.
Maybe there is a good reason - maybe its one we need to address.

The argument that 6 hours of investigation would - in any way - make a motorway 'safer' is laughable.
Motorways are a very mature technology - just because ours lag 30-50 years behind the rest of the world doesn't mean we're going to find new insights.
Put that money towards buying another few cm of motorway.

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#3504989 21-Jun-2026 11:04

You'd think an hour of very hi-res drone photography and the usual yard examination of crash vehicles would be enough for 95% of cases. Maybe not.

Dulouz

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#3504990 21-Jun-2026 11:18

There should be a secondary team (Police, NZTA, traffic management) set up to deal with re-rerouting of traffic in these situations - currently the attitude is 'sorry you'll just have to wait'.

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Technofreak

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#3504998 21-Jun-2026 12:20

I wasn't questioning the need to investigate/survey the scene. That is very important as is the care and help for the injured. As others have pointed out, the needs of the people stuck in the stopped vehicles also need to be considered.

My post was around two points

I was questioning the length of time required for the investigation. This time has increased significantly in recent years. We used to be able to get the job done in a much shorter time frame. With advances in technology you have to question why so much time is needed. Are such lengthy closures really justified, is there a better way to do it?
If such a long period of time is justified then there needs to be a plan to deal with the stopped/trapped traffic. 6 hours (even less) is an extreme amount of time to be stuck in your car going nowhere, even for healthy people. Lack of water, nowhere to go to the toilet etc. I know I'd be struggling to last that long without having a toilet stop. Unless I'm on a long trip I don't usually have water with me, so I'd probably be suffering from dehydration too. I'd hate to imagine what it'd be like with young children or elderly/health impaired people over that length of time.

I find it unbelievable that there was no plan to get those stuck in the queue out of the queue. We have plans for plenty of other disaster events, why not one for the likes of this. I believe there are options that can be used. They just take a bit of planning and organising.

Having been stuck in traffic like this previously I have seen ways in which drivers of trapped cars took it upon themselves to figure out a safe way to get out of the queue and on their way. It could have been done much more expeditiously if the authorities had implemented a plan to do it.

I read that the authorities involved in this event have doubled down and basically said that was the best they could do. I'm sorry I don't accept that answer. It saddens me that they seem to have their heads in the sand over this and don't acknowledge there was a problem and things could be done better,

While they no doubt did a magnificent job in caring for the injured and investigating the cause, they failed miserably in catering for those unfortunate people trapped for hours in their vehicles. I'm surprised there hasn't been a bigger outcry. Imagine the hullabaloo if it had only been 150 people stuck on an A320 for that long?

I hope this event is a trigger to review how the investigations are carried out and extraction plans are developed to avoid people from being trapped in stopped traffic for long periods of time.

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tweake

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#3505002 21-Jun-2026 13:04

Dulouz:

There should be a secondary team (Police, NZTA, traffic management) set up to deal with re-rerouting of traffic in these situations - currently the attitude is 'sorry you'll just have to wait'.

normally there is. i suspect one of the crowds was caught short staffed.

i used to live in a place where there was a lot of accidents. road closure was common. there was procedures in place. however talking to the cops, they where not happy that the contractors that did the road diversions kept changing and they didn't have any plans worked out before hand. we had a road closure some years back where they put the traffic down a back road and there was two accidents on that road. so they shut that and put all traffic through mangawhai waipu. those who know that road know its not suitable for trucks and a truck got stuck on one of the corners. that effectively cut off northland from rest of nz. people responsible for road diversions not having a plan or knowing what they are doing.

BlakJak

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#3505021 21-Jun-2026 14:02

There absolutely are all sorts of arrangements in place, and standard practices, for managing diversions - in my experience (and I have attended many serious crash incidents over the years - things are usually handled with more grace than in this particular case. Which makes me wonder what we don't know. And, given the media coverage and feedback that is no doubt being channelled through non GZ mediums, I'm sure this will be debriefed as a place to learn a lesson or two.

Serious Crash incidents are treated as crime scenes and the analysis takes some time, but they are not mucking about. They're just ensuring they have what they need to provide justice to all parties. This of course, after victim welfare (extrication,first aid and transfer to higher care) and once the investigation is complete, then repairs can be effected. All these things take time.

I'm sure part of the debrief would be, why didn't they u-turn stopped traffic sooner. 🤷

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empacher48

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#3505081 21-Jun-2026 15:28

I’ve seen roads across the South Island closed for up to 12 hours after an accident because the Serious Crash Unit wanted to investigate, but have had to drive 6 hours across the island to get to the scene because the only other unit was tied up somewhere else.

That road was the only access to many towns and villages with no other bypass option or alternative route.

I do safety investigations in transport for another sector, and it is always accepted that an accident scene may have to be disturbed in order to continue operations. But you manage that limitation and part of the gathering of evidence is noting where objects may have been moved and general disruption of the accident site.