Auckland Traffic Chaos

Yesterday, Saturday December 6th 2014, we had a little crash on the Auckland Harbour Bridge which resulted in 3 of the northbound traffic lanes being closed. This being being at around mid-day in the build-up to Christmas and the harbour bridge being one of the main pieces of transport infrastructure in Auckland resulted in a complete grid-lock for large parts of the central city and the motorway network.

NZHerald - 2014

So of course the question comes up, "Does Auckland need a better road network?"

Well it just so happens that this is one of the critical points on the Auckland motorway network that NZTA has known about for some time and hence they have been developing alternative plans for.

The first thing that NZTA has been doing is building the Western Ring Route (WRR) which is a complete alternative to SH1 through Auckland. If yesterdays crash happened in an Auckland where the WRR was complete we would have seen far less people being disrupted. We still would have seen congestion in much of the inner parts of Auckland as the WRR really does only provide for those going through Auckland or are living on the outer edges of the city.

The other project NZTA has in the works which is more directly related to this would have been the Additional Waitemata Harbour Crossing (AWHC). This project looks to replace the existing harbour bridges function as SH1 through auckland and leave the existing bridge to provide for local movements between the northshore and the city.

If we look closer at the AWHC it would have helped in 2 ways. Firstly the AWHC would be designed to a much higher standard in terms of road geometry and therefore it would be much less likely that the crash would have occurred at all. Secondly, had the crash occurred, either on the bridge or in the new tunnel, it would have left the other connection open and at full capacity.

Neither of the above 2 projects would result in there being zero impact, obviously when you loose 3 of the 4 northbound lanes on the only connection between the Northshore and the city you will get disruption. However, if these two projects were complete and we had this crash most of the city would not have even known or cared.

Moments like these we tend to get the various armchair experts coming out and expressing their opinion on what would fix the issue with one obvious call for better public transport. So one call we get is that if we had the Congestion Free Network (CFN) people would have been able to simply leave their cars at home and take the bus or the train to where they wanted to be. This of course misses the point, creating another isolated system doesn't create any redundancy or resilience but rather creates another layer where the same issue can happen again.

We actually see this currently with the existing motorway and rail networks.
When we have an issue on the motorway the motorway suffers and the rail network is fine.
When we have an issue on the rail network the rail network suffers and the motorway is fine.
In effect, the more layers you apply the greater the chance of having a failure, however the cost of that failure would be less as your usage would be more diverse.

So if we look at the rail side of things, one of the down sides of the Central Rail Link (CRL) is that we make our entire rail network dependant on the CRL being operational, all we will need is one breakdown or signal fault in the CRL and the entire rail network will need to stop, we have a similar issue with the electrification of the network.

So in terms of yesterdays event what would have it been like had we had the CFN? Well unfortunately with this being a weekend the likely result would have been very similar to what we saw, large amounts of congestion. The simple reason for this is that the types of trips people make in the weekend just aren't suited for public transport, of course some of them are however the majority aren't and this is why we see PT volumes taking a dive in the weekend whereas road volumes tend to carry on similar to that of a week day.