Every month we report on what’s happening with public transport patronage however Auckland Transport also report on many other metrics too such as how roads are performing. In this post I’ll look at some of those other metrics.

Instead of just measuring traffic volumes, AT use a measurement called Arterial Road Productivity which is a based on how many vehicles, how fast they’re travelling and how many people they have in them. To me this seems like a very bad metric primary because it only seems to count people in vehicles. It could also be interpreted as encouraging bigger and faster roads as a way of improving the metric which goes against many of the city’s wider goals. In saying that another way to improve the result could be improving vehicle occupancy so therefore bus lanes which speed up buses carrying more people will improve productivity. Regardless it seems that AT is performing quite well and is above target.

The second metric is AM Peak Arterial Road Level of Service and as you can see even then around 80% of arterials aren’t considered congested.

Aug-15 Road Productivity

The next set of charts look at how a number of key freight routes are performing. For each of these routes AT have a target for how long it should take to travel. As you can see for almost all of the routes the target has been at least met and some such as on Kaka St/James Fletcher Dr/Favona Rd/Walmsley Rd the target has been significantly exceeded. If the results here are indicative of other parts of the road network then they certainly don’t support calls from the freight industry for significant projects such as the East-West link.

Aug-15 Freight Routes 1

Aug-15 Freight Routes 2

Aug-15 Freight Routes 3

Parking obviously plays a big role in transport and AT measure occupancy rates for both on street and off street carparks. On street parks are only measured quarterly and the result is based on top four busiest hours of the day at each of the three sites around the city centre. The last survey occurred in August and as you can see at the upper level of AT’s target. This suggests there’s possibly room to increase prices to better manage demand.

Occupancy at AT’s off street carparks have dropped quite a bit recently which is almost certainly attributed to the change in parking prices at the beginning of August.

Aug-15 Parking Occupancy

One area that isn’t looking great is road safety with the number of deaths and injuries 6% above target.

Aug-15 Road deaths and injuries

While AT don’t publish monthly traffic volumes, the NZTA does for some selected state highways. The one we look at closest is the Harbour Bridge which is currently experiencing a growth rate of around 1% p.a. Compared to the other state highways that the NZTA publish this appears incredibly low as most are experiencing growth of around 5% annually – although off a lower base.Aug-15 AHB Traffic Volumes

Overall – with the exception of road safety – it seems that our local roads are not performing too badly.

Share this

20 comments

  1. One of the Auckland Conversation speakers talked about how the Level of Service metric creates massively over sized roads and is (or has been?) being phased out in the US

  2. I’m uncomfortable with doing research to promote a political agenda. (It’s done all the time but that doesn’t make it right.) AT’s data on road efficiency seem as good a measure of throughput as any. I understand very well that that is not the only way to measure a road’s role in a transport system, and as DLB points out, LoS is a flawed measure, but these guys are traffic people and they want and need to know this stuff. AT does a good job of statistical analysis of PT and many of their findings support additional investment in PT. Ultimately, the system as a whole needs to function efficiently with regard to moving *people* not vehicles around. Traffic engineers, and politicians especially, want see more “balance” between cars and PT. Of course, to achieve that theoretical balance, investment in PT must greatly outstrip that in highways so it catches up. However, that battle won’t be won on the basis of statistics, but it’s always best to have evidence close to hand.

  3. “AT use a measurement called Arterial Road Productivity which is a based on how many vehicles, how fast they’re travelling and how many people they have in them. To me this seems like a very bad metric primary because it only seems to count people in vehicles” – I presume you actually mean MOTOR vehicles. As I keep reminding people, a cycle is also a “vehicle” (and, like a car, is usually a “private vehicle” unless you have a bikeshare scheme).

    But I agree that better measures of “productivity” would be PEOPLE throughput (incl. those walking/biking), in the same way that we’re usually more interested in FREIGHT throughput (by tonnage or whatever preferred metric) rather than the number of trucks and goods vehicles going past.

    1. Well NZTA measure heavy and light vehicles, but as buses are defined as heavy, and heavy is assumed to mean trucks, we get the situation where the boom in Transit [buses] over the Harbour Bridge is used to argue for its importance as a freight corridor and the need for the additional road crossing. Whereas it more accurately shows a rise in people movements and Transit ones at that, which more clearly supports the next crossing priority being a direct Rapid Transit one.

      Steve, yeah sure, but what we count shows what we value; these aren’t bad metrics per se, just incomplete ones.

      1. There are no bad measures, only bad targets, and perverse behaviours by those tasked with achieving them.

        In this case, I’d say that arterial road productivity seems to be an output measure in that it relates to the quantity and quality of a good or service being provided by AT to Aucklanders. No different to “number of operations conducted” or “number of 3Hs”.

        Now, does arterial road productivity link to our desired outcomes? I would suggest that it links to MOT outcomes “Effective” transport system – one that moves people where they need to be in a timely manner, as well as Auckland Transport’s desired impact of “Auckland Transport’s network moves people and goods efficiently.”

        So, I would say it is a very good measure. Focused, clear, concise. The purpose of Auckland Transport is to move people and freight – the purpose isn’t to create a hipster paradise. Just like the purpose of the NZDF isn’t to employ the unemployed, so measures like “number of LSV volunteers used” is also stupid.

        There’s nothing wrong with bigger and faster roads per se. What might be a problem is the trade-offs of getting those bigger and faster roads vs other investments. But guess what? That’s not AT’s call, and shouldn’t be. That’s up to the politicians to decide.

    2. And not only is the productivity calculated that way that but its compared to an idealised system in which every vehicle in every lane travels at an average speed of 35km/hr.

      This has the perverse outcome that on a busy 2 lane arterial choked with 75% SOV’s and the rest a mix of buses, T2, T3 bikes, 20 full buses crawling along at 20 km/hr raises the productivity of that road dramatically because the sheer number of people in the buses moves the arterial productivity so much better. Even though the actual experience for everyone especially the PT users on that road is very poor, AT can justify that the road is performing well.

      And putting in bus or cycle lanes will improve the experience for the PT/cycle user further, but it will meet resistance from the 75% of SOV drivers who see no benefit to that arrangement.
      Even though those 75% of the vehicles are less than 50% of the people being moved down the corridor.

  4. Regarding road safety this really needs to be measured compared to number of vehicles/population. Capacity for the other measures can be increased etc to keep on target however for safety if it is not proportional then with more people and vehicles of course injuries etc will go up.

      1. That would be nice but there are differences between the two. Aviation has improved from safer aircraft and better pilot training along with improved navigation systems. Aircraft don’t have to avoid pedestrians, cyclists, trucks, buses, cars etc just aircraft and weather (and they are better at avoiding weather these days). Potentially automation (driverless cars) could make a difference along with other improvements (such as cycle lanes).

        1. I agree aviation is different, but the key thing that most airlines have is a safety first culture. I look at driving in NZ and that isn’t the case. Way too many distracted drivers, poorly maintained cars and driving at too higher speed for the environment. If we start fixing that then we can expect deaths and injuries on the road to decrease even as the population increases.

          1. You’ll never get zero deaths or injuries simply because you can never remove fools. There will come a point where regardless of technology and roading improvements people will still die.

          2. RB while ou may say that we’ll never achieve zero deaths that still does not mean that it should not be the aim. Zero is achievable but not with our current attitudes.

  5. (First impression – have other stuff to do) Interesting.

    It reminds me that I often don’t take my car not because I can’t get there…..but because when I get there I have nowhere to put the car. Plus I like riding trains and buses. So it’s an easy call.

  6. I always here people banging on about freight, and how important giant motorways are for it.

    Why don’t we just create dedicated freight and bus lanes along key motorway routes then? Reduced pollution (without trucks stopping/starting), increased productivity and you please the trucking lobby!

    1. Yes it’s odd that the trucking lobby never argue for that. Why is that? They’re always arguing for the next huge highways but never to just optimise the current ones for their vital business….?

      1. I’m sure the trucking firms would like that. But I suspect the sort of person who becomes a trucking lobbyist isn’t a trucker themselves. They just hitch to the “roads = good” bandwagon because they want to drive their XR8 down the motorway at 130km/h without anyone getting in the way. That tends to rub off in their advocacy.

        Truckers and trucking firms need better lobbyists.

  7. I wonder if we couldn’t come up with a really simple “Transport Productivity Metric” which is given in km/h

    What it could be is a share-weighted index of how long it takes to travel at different times… based on surveys of selected routes.

    Let’s say 9am-10am there are
    50% car users who travel at average 40kmh (based on door to door speed)
    25% bus users who travel at average 30kmh
    25% train users who travel at average 60kmh

    The Transport Productivity Metric would then be 42.5kmh

    A metric like this could lead to a focus on shifting people to faster modes e.g. the Northern Busway, rail-post-CRL

    You could also incorporate safety by including 1V data i.e. TPM/1V = final index, so a faster TPM but more accidents is a lower score and vice versa.

Leave a Reply