GPS manufacturer TomTom has released a new congestion report that shows relatively high congestion in Auckland and Wellington. Transportblog has some comments on the methodology, most of which I agree with.
One of the more interesting projects that I worked on in recent times was a research project for NZTA to develop ideas around measuring the performance of road and rail transport in New Zealand. Being economists we took a wellbeing (public welfare) approach, ie we looked at how transport generates benefits and costs that affect people’s happiness and overall life satisfaction. If you’re game you can read our long research report.
Transport creates wellbeing mostly indirectly by enabling people to do other things like visiting friends, buying stuff, earning money to buy stuff, getting an education to help them to earn money to buy stuff, etc. While some people do get pleasure directly from driving or riding a motorbike, these benefits are probably very small compared to the benefits from activities that transport enables. (Walking and cycling were out of our scope so we didn’t consider the health or pleasure benefits from these modes.)
One of the several dimensions of our proposed framework was the physical performance or efficiency of the transport system, ie its ability to move people and freight where and when needed. We suggested that such measures should focus on the movement of people and freight rather than vehicles. This is a somewhat subtle but important distinction.
Traditionally transport performance measures have focussed on movement of vehicles. This is possibly because vehicles are easy to count so you can get good data to analyse. You can also relatively easily calculate average speed or congestion measures that relate to the ability of vehicles to move around unimpeded.
However, vehicle-based measures obviously ignore the load that each vehicle is carrying, ie the number of passengers or volume of freight. Up to some point at least, by increasing loads it is possible to increase the ability of the transport system to move people and freight around without having to handle more vehicles.
So we proposed “throughput” based measures, taking loads into account, rather than vehicle-based measures such as congestion. For passenger vehicles you should take account of the number of people per vehicle, particularly for public transport buses. You can then calculate the performance of a road as the number of people that it’s able to move in a given time period. This is a bit more difficult because you have to measure loads somehow, but that’s not an insurmountable barrier (eg do some surveys), and new technologies (eg mobile phone detectors) could make it easier to get good data.
Throughput measures could also provide a useful basis for making transport investment decisions. If you analyse the movement of people and freight rather than vehicles, it will probably become clear that in some situations the best option is to increase vehicle loads rather than build more roads.
I don’t think our research had anything to do with it but in Auckland at least I think I’ve noticed a bit of shift in Auckland Transport’s thinking towards movement of people rather than vehicles. An example is their implementation of the new northbound Fanshawe Street bus lane, which has made peak-time travel faster for most people although possibly not for most vehicles. AT’s press release on this project references people movement clearly: “Seventy per cent of the people who travel on Fanshawe St at peak are in a bus and there’s a bus about every 40 seconds.”